1 // Algorithm implementation -*- C++ -*-
2
3 // Copyright (C) 2001-2016 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24
25 /*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
51 /** @file bits/stl_algo.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{algorithm}
54 */
55
56 #ifndef _STL_ALGO_H
57 #define _STL_ALGO_H 1
58
59 #include <cstdlib> // for rand
60 #include <bits/algorithmfwd.h>
61 #include <bits/stl_heap.h>
62 #include <bits/stl_tempbuf.h> // for _Temporary_buffer
63 #include <bits/predefined_ops.h>
64
65 #if __cplusplus >= 201103L
66 #include <bits/uniform_int_dist.h>
67 #endif
68
69 // See concept_check.h for the __glibcxx_*_requires macros.
70
_GLIBCXX_VISIBILITY(default)71 namespace std _GLIBCXX_VISIBILITY(default)
72 {
73 _GLIBCXX_BEGIN_NAMESPACE_VERSION
74
75 /// Swaps the median value of *__a, *__b and *__c under __comp to *__result
76 template<typename _Iterator, typename _Compare>
77 void
78 __move_median_to_first(_Iterator __result,_Iterator __a, _Iterator __b,
79 _Iterator __c, _Compare __comp)
80 {
81 if (__comp(__a, __b))
82 {
83 if (__comp(__b, __c))
84 std::iter_swap(__result, __b);
85 else if (__comp(__a, __c))
86 std::iter_swap(__result, __c);
87 else
88 std::iter_swap(__result, __a);
89 }
90 else if (__comp(__a, __c))
91 std::iter_swap(__result, __a);
92 else if (__comp(__b, __c))
93 std::iter_swap(__result, __c);
94 else
95 std::iter_swap(__result, __b);
96 }
97
98 /// This is an overload used by find algos for the Input Iterator case.
99 template<typename _InputIterator, typename _Predicate>
100 inline _InputIterator
101 __find_if(_InputIterator __first, _InputIterator __last,
102 _Predicate __pred, input_iterator_tag)
103 {
104 while (__first != __last && !__pred(__first))
105 ++__first;
106 return __first;
107 }
108
109 /// This is an overload used by find algos for the RAI case.
110 template<typename _RandomAccessIterator, typename _Predicate>
111 _RandomAccessIterator
112 __find_if(_RandomAccessIterator __first, _RandomAccessIterator __last,
113 _Predicate __pred, random_access_iterator_tag)
114 {
115 typename iterator_traits<_RandomAccessIterator>::difference_type
116 __trip_count = (__last - __first) >> 2;
117
118 for (; __trip_count > 0; --__trip_count)
119 {
120 if (__pred(__first))
121 return __first;
122 ++__first;
123
124 if (__pred(__first))
125 return __first;
126 ++__first;
127
128 if (__pred(__first))
129 return __first;
130 ++__first;
131
132 if (__pred(__first))
133 return __first;
134 ++__first;
135 }
136
137 switch (__last - __first)
138 {
139 case 3:
140 if (__pred(__first))
141 return __first;
142 ++__first;
143 case 2:
144 if (__pred(__first))
145 return __first;
146 ++__first;
147 case 1:
148 if (__pred(__first))
149 return __first;
150 ++__first;
151 case 0:
152 default:
153 return __last;
154 }
155 }
156
157 template<typename _Iterator, typename _Predicate>
158 inline _Iterator
159 __find_if(_Iterator __first, _Iterator __last, _Predicate __pred)
160 {
161 return __find_if(__first, __last, __pred,
162 std::__iterator_category(__first));
163 }
164
165 /// Provided for stable_partition to use.
166 template<typename _InputIterator, typename _Predicate>
167 inline _InputIterator
168 __find_if_not(_InputIterator __first, _InputIterator __last,
169 _Predicate __pred)
170 {
171 return std::__find_if(__first, __last,
172 __gnu_cxx::__ops::__negate(__pred),
173 std::__iterator_category(__first));
174 }
175
176 /// Like find_if_not(), but uses and updates a count of the
177 /// remaining range length instead of comparing against an end
178 /// iterator.
179 template<typename _InputIterator, typename _Predicate, typename _Distance>
180 _InputIterator
181 __find_if_not_n(_InputIterator __first, _Distance& __len, _Predicate __pred)
182 {
183 for (; __len; --__len, ++__first)
184 if (!__pred(__first))
185 break;
186 return __first;
187 }
188
189 // set_difference
190 // set_intersection
191 // set_symmetric_difference
192 // set_union
193 // for_each
194 // find
195 // find_if
196 // find_first_of
197 // adjacent_find
198 // count
199 // count_if
200 // search
201
202 template<typename _ForwardIterator1, typename _ForwardIterator2,
203 typename _BinaryPredicate>
204 _ForwardIterator1
205 __search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
206 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
207 _BinaryPredicate __predicate)
208 {
209 // Test for empty ranges
210 if (__first1 == __last1 || __first2 == __last2)
211 return __first1;
212
213 // Test for a pattern of length 1.
214 _ForwardIterator2 __p1(__first2);
215 if (++__p1 == __last2)
216 return std::__find_if(__first1, __last1,
217 __gnu_cxx::__ops::__iter_comp_iter(__predicate, __first2));
218
219 // General case.
220 _ForwardIterator2 __p;
221 _ForwardIterator1 __current = __first1;
222
223 for (;;)
224 {
225 __first1 =
226 std::__find_if(__first1, __last1,
227 __gnu_cxx::__ops::__iter_comp_iter(__predicate, __first2));
228
229 if (__first1 == __last1)
230 return __last1;
231
232 __p = __p1;
233 __current = __first1;
234 if (++__current == __last1)
235 return __last1;
236
237 while (__predicate(__current, __p))
238 {
239 if (++__p == __last2)
240 return __first1;
241 if (++__current == __last1)
242 return __last1;
243 }
244 ++__first1;
245 }
246 return __first1;
247 }
248
249 // search_n
250
251 /**
252 * This is an helper function for search_n overloaded for forward iterators.
253 */
254 template<typename _ForwardIterator, typename _Integer,
255 typename _UnaryPredicate>
256 _ForwardIterator
257 __search_n_aux(_ForwardIterator __first, _ForwardIterator __last,
258 _Integer __count, _UnaryPredicate __unary_pred,
259 std::forward_iterator_tag)
260 {
261 __first = std::__find_if(__first, __last, __unary_pred);
262 while (__first != __last)
263 {
264 typename iterator_traits<_ForwardIterator>::difference_type
265 __n = __count;
266 _ForwardIterator __i = __first;
267 ++__i;
268 while (__i != __last && __n != 1 && __unary_pred(__i))
269 {
270 ++__i;
271 --__n;
272 }
273 if (__n == 1)
274 return __first;
275 if (__i == __last)
276 return __last;
277 __first = std::__find_if(++__i, __last, __unary_pred);
278 }
279 return __last;
280 }
281
282 /**
283 * This is an helper function for search_n overloaded for random access
284 * iterators.
285 */
286 template<typename _RandomAccessIter, typename _Integer,
287 typename _UnaryPredicate>
288 _RandomAccessIter
289 __search_n_aux(_RandomAccessIter __first, _RandomAccessIter __last,
290 _Integer __count, _UnaryPredicate __unary_pred,
291 std::random_access_iterator_tag)
292 {
293 typedef typename std::iterator_traits<_RandomAccessIter>::difference_type
294 _DistanceType;
295
296 _DistanceType __tailSize = __last - __first;
297 _DistanceType __remainder = __count;
298
299 while (__remainder <= __tailSize) // the main loop...
300 {
301 __first += __remainder;
302 __tailSize -= __remainder;
303 // __first here is always pointing to one past the last element of
304 // next possible match.
305 _RandomAccessIter __backTrack = __first;
306 while (__unary_pred(--__backTrack))
307 {
308 if (--__remainder == 0)
309 return (__first - __count); // Success
310 }
311 __remainder = __count + 1 - (__first - __backTrack);
312 }
313 return __last; // Failure
314 }
315
316 template<typename _ForwardIterator, typename _Integer,
317 typename _UnaryPredicate>
318 _ForwardIterator
319 __search_n(_ForwardIterator __first, _ForwardIterator __last,
320 _Integer __count,
321 _UnaryPredicate __unary_pred)
322 {
323 if (__count <= 0)
324 return __first;
325
326 if (__count == 1)
327 return std::__find_if(__first, __last, __unary_pred);
328
329 return std::__search_n_aux(__first, __last, __count, __unary_pred,
330 std::__iterator_category(__first));
331 }
332
333 // find_end for forward iterators.
334 template<typename _ForwardIterator1, typename _ForwardIterator2,
335 typename _BinaryPredicate>
336 _ForwardIterator1
337 __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
338 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
339 forward_iterator_tag, forward_iterator_tag,
340 _BinaryPredicate __comp)
341 {
342 if (__first2 == __last2)
343 return __last1;
344
345 _ForwardIterator1 __result = __last1;
346 while (1)
347 {
348 _ForwardIterator1 __new_result
349 = std::__search(__first1, __last1, __first2, __last2, __comp);
350 if (__new_result == __last1)
351 return __result;
352 else
353 {
354 __result = __new_result;
355 __first1 = __new_result;
356 ++__first1;
357 }
358 }
359 }
360
361 // find_end for bidirectional iterators (much faster).
362 template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
363 typename _BinaryPredicate>
364 _BidirectionalIterator1
365 __find_end(_BidirectionalIterator1 __first1,
366 _BidirectionalIterator1 __last1,
367 _BidirectionalIterator2 __first2,
368 _BidirectionalIterator2 __last2,
369 bidirectional_iterator_tag, bidirectional_iterator_tag,
370 _BinaryPredicate __comp)
371 {
372 // concept requirements
373 __glibcxx_function_requires(_BidirectionalIteratorConcept<
374 _BidirectionalIterator1>)
375 __glibcxx_function_requires(_BidirectionalIteratorConcept<
376 _BidirectionalIterator2>)
377
378 typedef reverse_iterator<_BidirectionalIterator1> _RevIterator1;
379 typedef reverse_iterator<_BidirectionalIterator2> _RevIterator2;
380
381 _RevIterator1 __rlast1(__first1);
382 _RevIterator2 __rlast2(__first2);
383 _RevIterator1 __rresult = std::__search(_RevIterator1(__last1), __rlast1,
384 _RevIterator2(__last2), __rlast2,
385 __comp);
386
387 if (__rresult == __rlast1)
388 return __last1;
389 else
390 {
391 _BidirectionalIterator1 __result = __rresult.base();
392 std::advance(__result, -std::distance(__first2, __last2));
393 return __result;
394 }
395 }
396
397 /**
398 * @brief Find last matching subsequence in a sequence.
399 * @ingroup non_mutating_algorithms
400 * @param __first1 Start of range to search.
401 * @param __last1 End of range to search.
402 * @param __first2 Start of sequence to match.
403 * @param __last2 End of sequence to match.
404 * @return The last iterator @c i in the range
405 * @p [__first1,__last1-(__last2-__first2)) such that @c *(i+N) ==
406 * @p *(__first2+N) for each @c N in the range @p
407 * [0,__last2-__first2), or @p __last1 if no such iterator exists.
408 *
409 * Searches the range @p [__first1,__last1) for a sub-sequence that
410 * compares equal value-by-value with the sequence given by @p
411 * [__first2,__last2) and returns an iterator to the __first
412 * element of the sub-sequence, or @p __last1 if the sub-sequence
413 * is not found. The sub-sequence will be the last such
414 * subsequence contained in [__first1,__last1).
415 *
416 * Because the sub-sequence must lie completely within the range @p
417 * [__first1,__last1) it must start at a position less than @p
418 * __last1-(__last2-__first2) where @p __last2-__first2 is the
419 * length of the sub-sequence. This means that the returned
420 * iterator @c i will be in the range @p
421 * [__first1,__last1-(__last2-__first2))
422 */
423 template<typename _ForwardIterator1, typename _ForwardIterator2>
424 inline _ForwardIterator1
425 find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
426 _ForwardIterator2 __first2, _ForwardIterator2 __last2)
427 {
428 // concept requirements
429 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
430 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
431 __glibcxx_function_requires(_EqualOpConcept<
432 typename iterator_traits<_ForwardIterator1>::value_type,
433 typename iterator_traits<_ForwardIterator2>::value_type>)
434 __glibcxx_requires_valid_range(__first1, __last1);
435 __glibcxx_requires_valid_range(__first2, __last2);
436
437 return std::__find_end(__first1, __last1, __first2, __last2,
438 std::__iterator_category(__first1),
439 std::__iterator_category(__first2),
440 __gnu_cxx::__ops::__iter_equal_to_iter());
441 }
442
443 /**
444 * @brief Find last matching subsequence in a sequence using a predicate.
445 * @ingroup non_mutating_algorithms
446 * @param __first1 Start of range to search.
447 * @param __last1 End of range to search.
448 * @param __first2 Start of sequence to match.
449 * @param __last2 End of sequence to match.
450 * @param __comp The predicate to use.
451 * @return The last iterator @c i in the range @p
452 * [__first1,__last1-(__last2-__first2)) such that @c
453 * predicate(*(i+N), @p (__first2+N)) is true for each @c N in the
454 * range @p [0,__last2-__first2), or @p __last1 if no such iterator
455 * exists.
456 *
457 * Searches the range @p [__first1,__last1) for a sub-sequence that
458 * compares equal value-by-value with the sequence given by @p
459 * [__first2,__last2) using comp as a predicate and returns an
460 * iterator to the first element of the sub-sequence, or @p __last1
461 * if the sub-sequence is not found. The sub-sequence will be the
462 * last such subsequence contained in [__first,__last1).
463 *
464 * Because the sub-sequence must lie completely within the range @p
465 * [__first1,__last1) it must start at a position less than @p
466 * __last1-(__last2-__first2) where @p __last2-__first2 is the
467 * length of the sub-sequence. This means that the returned
468 * iterator @c i will be in the range @p
469 * [__first1,__last1-(__last2-__first2))
470 */
471 template<typename _ForwardIterator1, typename _ForwardIterator2,
472 typename _BinaryPredicate>
473 inline _ForwardIterator1
474 find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
475 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
476 _BinaryPredicate __comp)
477 {
478 // concept requirements
479 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
480 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
481 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
482 typename iterator_traits<_ForwardIterator1>::value_type,
483 typename iterator_traits<_ForwardIterator2>::value_type>)
484 __glibcxx_requires_valid_range(__first1, __last1);
485 __glibcxx_requires_valid_range(__first2, __last2);
486
487 return std::__find_end(__first1, __last1, __first2, __last2,
488 std::__iterator_category(__first1),
489 std::__iterator_category(__first2),
490 __gnu_cxx::__ops::__iter_comp_iter(__comp));
491 }
492
493 #if __cplusplus >= 201103L
494 /**
495 * @brief Checks that a predicate is true for all the elements
496 * of a sequence.
497 * @ingroup non_mutating_algorithms
498 * @param __first An input iterator.
499 * @param __last An input iterator.
500 * @param __pred A predicate.
501 * @return True if the check is true, false otherwise.
502 *
503 * Returns true if @p __pred is true for each element in the range
504 * @p [__first,__last), and false otherwise.
505 */
506 template<typename _InputIterator, typename _Predicate>
507 inline bool
508 all_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
509 { return __last == std::find_if_not(__first, __last, __pred); }
510
511 /**
512 * @brief Checks that a predicate is false for all the elements
513 * of a sequence.
514 * @ingroup non_mutating_algorithms
515 * @param __first An input iterator.
516 * @param __last An input iterator.
517 * @param __pred A predicate.
518 * @return True if the check is true, false otherwise.
519 *
520 * Returns true if @p __pred is false for each element in the range
521 * @p [__first,__last), and false otherwise.
522 */
523 template<typename _InputIterator, typename _Predicate>
524 inline bool
525 none_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
526 { return __last == _GLIBCXX_STD_A::find_if(__first, __last, __pred); }
527
528 /**
529 * @brief Checks that a predicate is false for at least an element
530 * of a sequence.
531 * @ingroup non_mutating_algorithms
532 * @param __first An input iterator.
533 * @param __last An input iterator.
534 * @param __pred A predicate.
535 * @return True if the check is true, false otherwise.
536 *
537 * Returns true if an element exists in the range @p
538 * [__first,__last) such that @p __pred is true, and false
539 * otherwise.
540 */
541 template<typename _InputIterator, typename _Predicate>
542 inline bool
543 any_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
544 { return !std::none_of(__first, __last, __pred); }
545
546 /**
547 * @brief Find the first element in a sequence for which a
548 * predicate is false.
549 * @ingroup non_mutating_algorithms
550 * @param __first An input iterator.
551 * @param __last An input iterator.
552 * @param __pred A predicate.
553 * @return The first iterator @c i in the range @p [__first,__last)
554 * such that @p __pred(*i) is false, or @p __last if no such iterator exists.
555 */
556 template<typename _InputIterator, typename _Predicate>
557 inline _InputIterator
558 find_if_not(_InputIterator __first, _InputIterator __last,
559 _Predicate __pred)
560 {
561 // concept requirements
562 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
563 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
564 typename iterator_traits<_InputIterator>::value_type>)
565 __glibcxx_requires_valid_range(__first, __last);
566 return std::__find_if_not(__first, __last,
567 __gnu_cxx::__ops::__pred_iter(__pred));
568 }
569
570 /**
571 * @brief Checks whether the sequence is partitioned.
572 * @ingroup mutating_algorithms
573 * @param __first An input iterator.
574 * @param __last An input iterator.
575 * @param __pred A predicate.
576 * @return True if the range @p [__first,__last) is partioned by @p __pred,
577 * i.e. if all elements that satisfy @p __pred appear before those that
578 * do not.
579 */
580 template<typename _InputIterator, typename _Predicate>
581 inline bool
582 is_partitioned(_InputIterator __first, _InputIterator __last,
583 _Predicate __pred)
584 {
585 __first = std::find_if_not(__first, __last, __pred);
586 return std::none_of(__first, __last, __pred);
587 }
588
589 /**
590 * @brief Find the partition point of a partitioned range.
591 * @ingroup mutating_algorithms
592 * @param __first An iterator.
593 * @param __last Another iterator.
594 * @param __pred A predicate.
595 * @return An iterator @p mid such that @p all_of(__first, mid, __pred)
596 * and @p none_of(mid, __last, __pred) are both true.
597 */
598 template<typename _ForwardIterator, typename _Predicate>
599 _ForwardIterator
600 partition_point(_ForwardIterator __first, _ForwardIterator __last,
601 _Predicate __pred)
602 {
603 // concept requirements
604 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
605 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
606 typename iterator_traits<_ForwardIterator>::value_type>)
607
608 // A specific debug-mode test will be necessary...
609 __glibcxx_requires_valid_range(__first, __last);
610
611 typedef typename iterator_traits<_ForwardIterator>::difference_type
612 _DistanceType;
613
614 _DistanceType __len = std::distance(__first, __last);
615 _DistanceType __half;
616 _ForwardIterator __middle;
617
618 while (__len > 0)
619 {
620 __half = __len >> 1;
621 __middle = __first;
622 std::advance(__middle, __half);
623 if (__pred(*__middle))
624 {
625 __first = __middle;
626 ++__first;
627 __len = __len - __half - 1;
628 }
629 else
630 __len = __half;
631 }
632 return __first;
633 }
634 #endif
635
636 template<typename _InputIterator, typename _OutputIterator,
637 typename _Predicate>
638 _OutputIterator
639 __remove_copy_if(_InputIterator __first, _InputIterator __last,
640 _OutputIterator __result, _Predicate __pred)
641 {
642 for (; __first != __last; ++__first)
643 if (!__pred(__first))
644 {
645 *__result = *__first;
646 ++__result;
647 }
648 return __result;
649 }
650
651 /**
652 * @brief Copy a sequence, removing elements of a given value.
653 * @ingroup mutating_algorithms
654 * @param __first An input iterator.
655 * @param __last An input iterator.
656 * @param __result An output iterator.
657 * @param __value The value to be removed.
658 * @return An iterator designating the end of the resulting sequence.
659 *
660 * Copies each element in the range @p [__first,__last) not equal
661 * to @p __value to the range beginning at @p __result.
662 * remove_copy() is stable, so the relative order of elements that
663 * are copied is unchanged.
664 */
665 template<typename _InputIterator, typename _OutputIterator, typename _Tp>
666 inline _OutputIterator
667 remove_copy(_InputIterator __first, _InputIterator __last,
668 _OutputIterator __result, const _Tp& __value)
669 {
670 // concept requirements
671 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
672 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
673 typename iterator_traits<_InputIterator>::value_type>)
674 __glibcxx_function_requires(_EqualOpConcept<
675 typename iterator_traits<_InputIterator>::value_type, _Tp>)
676 __glibcxx_requires_valid_range(__first, __last);
677
678 return std::__remove_copy_if(__first, __last, __result,
679 __gnu_cxx::__ops::__iter_equals_val(__value));
680 }
681
682 /**
683 * @brief Copy a sequence, removing elements for which a predicate is true.
684 * @ingroup mutating_algorithms
685 * @param __first An input iterator.
686 * @param __last An input iterator.
687 * @param __result An output iterator.
688 * @param __pred A predicate.
689 * @return An iterator designating the end of the resulting sequence.
690 *
691 * Copies each element in the range @p [__first,__last) for which
692 * @p __pred returns false to the range beginning at @p __result.
693 *
694 * remove_copy_if() is stable, so the relative order of elements that are
695 * copied is unchanged.
696 */
697 template<typename _InputIterator, typename _OutputIterator,
698 typename _Predicate>
699 inline _OutputIterator
700 remove_copy_if(_InputIterator __first, _InputIterator __last,
701 _OutputIterator __result, _Predicate __pred)
702 {
703 // concept requirements
704 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
705 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
706 typename iterator_traits<_InputIterator>::value_type>)
707 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
708 typename iterator_traits<_InputIterator>::value_type>)
709 __glibcxx_requires_valid_range(__first, __last);
710
711 return std::__remove_copy_if(__first, __last, __result,
712 __gnu_cxx::__ops::__pred_iter(__pred));
713 }
714
715 #if __cplusplus >= 201103L
716 /**
717 * @brief Copy the elements of a sequence for which a predicate is true.
718 * @ingroup mutating_algorithms
719 * @param __first An input iterator.
720 * @param __last An input iterator.
721 * @param __result An output iterator.
722 * @param __pred A predicate.
723 * @return An iterator designating the end of the resulting sequence.
724 *
725 * Copies each element in the range @p [__first,__last) for which
726 * @p __pred returns true to the range beginning at @p __result.
727 *
728 * copy_if() is stable, so the relative order of elements that are
729 * copied is unchanged.
730 */
731 template<typename _InputIterator, typename _OutputIterator,
732 typename _Predicate>
733 _OutputIterator
734 copy_if(_InputIterator __first, _InputIterator __last,
735 _OutputIterator __result, _Predicate __pred)
736 {
737 // concept requirements
738 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
739 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
740 typename iterator_traits<_InputIterator>::value_type>)
741 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
742 typename iterator_traits<_InputIterator>::value_type>)
743 __glibcxx_requires_valid_range(__first, __last);
744
745 for (; __first != __last; ++__first)
746 if (__pred(*__first))
747 {
748 *__result = *__first;
749 ++__result;
750 }
751 return __result;
752 }
753
754 template<typename _InputIterator, typename _Size, typename _OutputIterator>
755 _OutputIterator
756 __copy_n(_InputIterator __first, _Size __n,
757 _OutputIterator __result, input_iterator_tag)
758 {
759 if (__n > 0)
760 {
761 while (true)
762 {
763 *__result = *__first;
764 ++__result;
765 if (--__n > 0)
766 ++__first;
767 else
768 break;
769 }
770 }
771 return __result;
772 }
773
774 template<typename _RandomAccessIterator, typename _Size,
775 typename _OutputIterator>
776 inline _OutputIterator
777 __copy_n(_RandomAccessIterator __first, _Size __n,
778 _OutputIterator __result, random_access_iterator_tag)
779 { return std::copy(__first, __first + __n, __result); }
780
781 /**
782 * @brief Copies the range [first,first+n) into [result,result+n).
783 * @ingroup mutating_algorithms
784 * @param __first An input iterator.
785 * @param __n The number of elements to copy.
786 * @param __result An output iterator.
787 * @return result+n.
788 *
789 * This inline function will boil down to a call to @c memmove whenever
790 * possible. Failing that, if random access iterators are passed, then the
791 * loop count will be known (and therefore a candidate for compiler
792 * optimizations such as unrolling).
793 */
794 template<typename _InputIterator, typename _Size, typename _OutputIterator>
795 inline _OutputIterator
796 copy_n(_InputIterator __first, _Size __n, _OutputIterator __result)
797 {
798 // concept requirements
799 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
800 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
801 typename iterator_traits<_InputIterator>::value_type>)
802
803 return std::__copy_n(__first, __n, __result,
804 std::__iterator_category(__first));
805 }
806
807 /**
808 * @brief Copy the elements of a sequence to separate output sequences
809 * depending on the truth value of a predicate.
810 * @ingroup mutating_algorithms
811 * @param __first An input iterator.
812 * @param __last An input iterator.
813 * @param __out_true An output iterator.
814 * @param __out_false An output iterator.
815 * @param __pred A predicate.
816 * @return A pair designating the ends of the resulting sequences.
817 *
818 * Copies each element in the range @p [__first,__last) for which
819 * @p __pred returns true to the range beginning at @p out_true
820 * and each element for which @p __pred returns false to @p __out_false.
821 */
822 template<typename _InputIterator, typename _OutputIterator1,
823 typename _OutputIterator2, typename _Predicate>
824 pair<_OutputIterator1, _OutputIterator2>
825 partition_copy(_InputIterator __first, _InputIterator __last,
826 _OutputIterator1 __out_true, _OutputIterator2 __out_false,
827 _Predicate __pred)
828 {
829 // concept requirements
830 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
831 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator1,
832 typename iterator_traits<_InputIterator>::value_type>)
833 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator2,
834 typename iterator_traits<_InputIterator>::value_type>)
835 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
836 typename iterator_traits<_InputIterator>::value_type>)
837 __glibcxx_requires_valid_range(__first, __last);
838
839 for (; __first != __last; ++__first)
840 if (__pred(*__first))
841 {
842 *__out_true = *__first;
843 ++__out_true;
844 }
845 else
846 {
847 *__out_false = *__first;
848 ++__out_false;
849 }
850
851 return pair<_OutputIterator1, _OutputIterator2>(__out_true, __out_false);
852 }
853 #endif
854
855 template<typename _ForwardIterator, typename _Predicate>
856 _ForwardIterator
857 __remove_if(_ForwardIterator __first, _ForwardIterator __last,
858 _Predicate __pred)
859 {
860 __first = std::__find_if(__first, __last, __pred);
861 if (__first == __last)
862 return __first;
863 _ForwardIterator __result = __first;
864 ++__first;
865 for (; __first != __last; ++__first)
866 if (!__pred(__first))
867 {
868 *__result = _GLIBCXX_MOVE(*__first);
869 ++__result;
870 }
871 return __result;
872 }
873
874 /**
875 * @brief Remove elements from a sequence.
876 * @ingroup mutating_algorithms
877 * @param __first An input iterator.
878 * @param __last An input iterator.
879 * @param __value The value to be removed.
880 * @return An iterator designating the end of the resulting sequence.
881 *
882 * All elements equal to @p __value are removed from the range
883 * @p [__first,__last).
884 *
885 * remove() is stable, so the relative order of elements that are
886 * not removed is unchanged.
887 *
888 * Elements between the end of the resulting sequence and @p __last
889 * are still present, but their value is unspecified.
890 */
891 template<typename _ForwardIterator, typename _Tp>
892 inline _ForwardIterator
893 remove(_ForwardIterator __first, _ForwardIterator __last,
894 const _Tp& __value)
895 {
896 // concept requirements
897 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
898 _ForwardIterator>)
899 __glibcxx_function_requires(_EqualOpConcept<
900 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
901 __glibcxx_requires_valid_range(__first, __last);
902
903 return std::__remove_if(__first, __last,
904 __gnu_cxx::__ops::__iter_equals_val(__value));
905 }
906
907 /**
908 * @brief Remove elements from a sequence using a predicate.
909 * @ingroup mutating_algorithms
910 * @param __first A forward iterator.
911 * @param __last A forward iterator.
912 * @param __pred A predicate.
913 * @return An iterator designating the end of the resulting sequence.
914 *
915 * All elements for which @p __pred returns true are removed from the range
916 * @p [__first,__last).
917 *
918 * remove_if() is stable, so the relative order of elements that are
919 * not removed is unchanged.
920 *
921 * Elements between the end of the resulting sequence and @p __last
922 * are still present, but their value is unspecified.
923 */
924 template<typename _ForwardIterator, typename _Predicate>
925 inline _ForwardIterator
926 remove_if(_ForwardIterator __first, _ForwardIterator __last,
927 _Predicate __pred)
928 {
929 // concept requirements
930 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
931 _ForwardIterator>)
932 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
933 typename iterator_traits<_ForwardIterator>::value_type>)
934 __glibcxx_requires_valid_range(__first, __last);
935
936 return std::__remove_if(__first, __last,
937 __gnu_cxx::__ops::__pred_iter(__pred));
938 }
939
940 template<typename _ForwardIterator, typename _BinaryPredicate>
941 _ForwardIterator
942 __adjacent_find(_ForwardIterator __first, _ForwardIterator __last,
943 _BinaryPredicate __binary_pred)
944 {
945 if (__first == __last)
946 return __last;
947 _ForwardIterator __next = __first;
948 while (++__next != __last)
949 {
950 if (__binary_pred(__first, __next))
951 return __first;
952 __first = __next;
953 }
954 return __last;
955 }
956
957 template<typename _ForwardIterator, typename _BinaryPredicate>
958 _ForwardIterator
959 __unique(_ForwardIterator __first, _ForwardIterator __last,
960 _BinaryPredicate __binary_pred)
961 {
962 // Skip the beginning, if already unique.
963 __first = std::__adjacent_find(__first, __last, __binary_pred);
964 if (__first == __last)
965 return __last;
966
967 // Do the real copy work.
968 _ForwardIterator __dest = __first;
969 ++__first;
970 while (++__first != __last)
971 if (!__binary_pred(__dest, __first))
972 *++__dest = _GLIBCXX_MOVE(*__first);
973 return ++__dest;
974 }
975
976 /**
977 * @brief Remove consecutive duplicate values from a sequence.
978 * @ingroup mutating_algorithms
979 * @param __first A forward iterator.
980 * @param __last A forward iterator.
981 * @return An iterator designating the end of the resulting sequence.
982 *
983 * Removes all but the first element from each group of consecutive
984 * values that compare equal.
985 * unique() is stable, so the relative order of elements that are
986 * not removed is unchanged.
987 * Elements between the end of the resulting sequence and @p __last
988 * are still present, but their value is unspecified.
989 */
990 template<typename _ForwardIterator>
991 inline _ForwardIterator
992 unique(_ForwardIterator __first, _ForwardIterator __last)
993 {
994 // concept requirements
995 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
996 _ForwardIterator>)
997 __glibcxx_function_requires(_EqualityComparableConcept<
998 typename iterator_traits<_ForwardIterator>::value_type>)
999 __glibcxx_requires_valid_range(__first, __last);
1000
1001 return std::__unique(__first, __last,
1002 __gnu_cxx::__ops::__iter_equal_to_iter());
1003 }
1004
1005 /**
1006 * @brief Remove consecutive values from a sequence using a predicate.
1007 * @ingroup mutating_algorithms
1008 * @param __first A forward iterator.
1009 * @param __last A forward iterator.
1010 * @param __binary_pred A binary predicate.
1011 * @return An iterator designating the end of the resulting sequence.
1012 *
1013 * Removes all but the first element from each group of consecutive
1014 * values for which @p __binary_pred returns true.
1015 * unique() is stable, so the relative order of elements that are
1016 * not removed is unchanged.
1017 * Elements between the end of the resulting sequence and @p __last
1018 * are still present, but their value is unspecified.
1019 */
1020 template<typename _ForwardIterator, typename _BinaryPredicate>
1021 inline _ForwardIterator
1022 unique(_ForwardIterator __first, _ForwardIterator __last,
1023 _BinaryPredicate __binary_pred)
1024 {
1025 // concept requirements
1026 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
1027 _ForwardIterator>)
1028 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
1029 typename iterator_traits<_ForwardIterator>::value_type,
1030 typename iterator_traits<_ForwardIterator>::value_type>)
1031 __glibcxx_requires_valid_range(__first, __last);
1032
1033 return std::__unique(__first, __last,
1034 __gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
1035 }
1036
1037 /**
1038 * This is an uglified
1039 * unique_copy(_InputIterator, _InputIterator, _OutputIterator,
1040 * _BinaryPredicate)
1041 * overloaded for forward iterators and output iterator as result.
1042 */
1043 template<typename _ForwardIterator, typename _OutputIterator,
1044 typename _BinaryPredicate>
1045 _OutputIterator
1046 __unique_copy(_ForwardIterator __first, _ForwardIterator __last,
1047 _OutputIterator __result, _BinaryPredicate __binary_pred,
1048 forward_iterator_tag, output_iterator_tag)
1049 {
1050 // concept requirements -- iterators already checked
1051 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
1052 typename iterator_traits<_ForwardIterator>::value_type,
1053 typename iterator_traits<_ForwardIterator>::value_type>)
1054
1055 _ForwardIterator __next = __first;
1056 *__result = *__first;
1057 while (++__next != __last)
1058 if (!__binary_pred(__first, __next))
1059 {
1060 __first = __next;
1061 *++__result = *__first;
1062 }
1063 return ++__result;
1064 }
1065
1066 /**
1067 * This is an uglified
1068 * unique_copy(_InputIterator, _InputIterator, _OutputIterator,
1069 * _BinaryPredicate)
1070 * overloaded for input iterators and output iterator as result.
1071 */
1072 template<typename _InputIterator, typename _OutputIterator,
1073 typename _BinaryPredicate>
1074 _OutputIterator
1075 __unique_copy(_InputIterator __first, _InputIterator __last,
1076 _OutputIterator __result, _BinaryPredicate __binary_pred,
1077 input_iterator_tag, output_iterator_tag)
1078 {
1079 // concept requirements -- iterators already checked
1080 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
1081 typename iterator_traits<_InputIterator>::value_type,
1082 typename iterator_traits<_InputIterator>::value_type>)
1083
1084 typename iterator_traits<_InputIterator>::value_type __value = *__first;
1085 __decltype(__gnu_cxx::__ops::__iter_comp_val(__binary_pred))
1086 __rebound_pred
1087 = __gnu_cxx::__ops::__iter_comp_val(__binary_pred);
1088 *__result = __value;
1089 while (++__first != __last)
1090 if (!__rebound_pred(__first, __value))
1091 {
1092 __value = *__first;
1093 *++__result = __value;
1094 }
1095 return ++__result;
1096 }
1097
1098 /**
1099 * This is an uglified
1100 * unique_copy(_InputIterator, _InputIterator, _OutputIterator,
1101 * _BinaryPredicate)
1102 * overloaded for input iterators and forward iterator as result.
1103 */
1104 template<typename _InputIterator, typename _ForwardIterator,
1105 typename _BinaryPredicate>
1106 _ForwardIterator
1107 __unique_copy(_InputIterator __first, _InputIterator __last,
1108 _ForwardIterator __result, _BinaryPredicate __binary_pred,
1109 input_iterator_tag, forward_iterator_tag)
1110 {
1111 // concept requirements -- iterators already checked
1112 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
1113 typename iterator_traits<_ForwardIterator>::value_type,
1114 typename iterator_traits<_InputIterator>::value_type>)
1115 *__result = *__first;
1116 while (++__first != __last)
1117 if (!__binary_pred(__result, __first))
1118 *++__result = *__first;
1119 return ++__result;
1120 }
1121
1122 /**
1123 * This is an uglified reverse(_BidirectionalIterator,
1124 * _BidirectionalIterator)
1125 * overloaded for bidirectional iterators.
1126 */
1127 template<typename _BidirectionalIterator>
1128 void
1129 __reverse(_BidirectionalIterator __first, _BidirectionalIterator __last,
1130 bidirectional_iterator_tag)
1131 {
1132 while (true)
1133 if (__first == __last || __first == --__last)
1134 return;
1135 else
1136 {
1137 std::iter_swap(__first, __last);
1138 ++__first;
1139 }
1140 }
1141
1142 /**
1143 * This is an uglified reverse(_BidirectionalIterator,
1144 * _BidirectionalIterator)
1145 * overloaded for random access iterators.
1146 */
1147 template<typename _RandomAccessIterator>
1148 void
1149 __reverse(_RandomAccessIterator __first, _RandomAccessIterator __last,
1150 random_access_iterator_tag)
1151 {
1152 if (__first == __last)
1153 return;
1154 --__last;
1155 while (__first < __last)
1156 {
1157 std::iter_swap(__first, __last);
1158 ++__first;
1159 --__last;
1160 }
1161 }
1162
1163 /**
1164 * @brief Reverse a sequence.
1165 * @ingroup mutating_algorithms
1166 * @param __first A bidirectional iterator.
1167 * @param __last A bidirectional iterator.
1168 * @return reverse() returns no value.
1169 *
1170 * Reverses the order of the elements in the range @p [__first,__last),
1171 * so that the first element becomes the last etc.
1172 * For every @c i such that @p 0<=i<=(__last-__first)/2), @p reverse()
1173 * swaps @p *(__first+i) and @p *(__last-(i+1))
1174 */
1175 template<typename _BidirectionalIterator>
1176 inline void
1177 reverse(_BidirectionalIterator __first, _BidirectionalIterator __last)
1178 {
1179 // concept requirements
1180 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
1181 _BidirectionalIterator>)
1182 __glibcxx_requires_valid_range(__first, __last);
1183 std::__reverse(__first, __last, std::__iterator_category(__first));
1184 }
1185
1186 /**
1187 * @brief Copy a sequence, reversing its elements.
1188 * @ingroup mutating_algorithms
1189 * @param __first A bidirectional iterator.
1190 * @param __last A bidirectional iterator.
1191 * @param __result An output iterator.
1192 * @return An iterator designating the end of the resulting sequence.
1193 *
1194 * Copies the elements in the range @p [__first,__last) to the
1195 * range @p [__result,__result+(__last-__first)) such that the
1196 * order of the elements is reversed. For every @c i such that @p
1197 * 0<=i<=(__last-__first), @p reverse_copy() performs the
1198 * assignment @p *(__result+(__last-__first)-1-i) = *(__first+i).
1199 * The ranges @p [__first,__last) and @p
1200 * [__result,__result+(__last-__first)) must not overlap.
1201 */
1202 template<typename _BidirectionalIterator, typename _OutputIterator>
1203 _OutputIterator
1204 reverse_copy(_BidirectionalIterator __first, _BidirectionalIterator __last,
1205 _OutputIterator __result)
1206 {
1207 // concept requirements
1208 __glibcxx_function_requires(_BidirectionalIteratorConcept<
1209 _BidirectionalIterator>)
1210 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
1211 typename iterator_traits<_BidirectionalIterator>::value_type>)
1212 __glibcxx_requires_valid_range(__first, __last);
1213
1214 while (__first != __last)
1215 {
1216 --__last;
1217 *__result = *__last;
1218 ++__result;
1219 }
1220 return __result;
1221 }
1222
1223 /**
1224 * This is a helper function for the rotate algorithm specialized on RAIs.
1225 * It returns the greatest common divisor of two integer values.
1226 */
1227 template<typename _EuclideanRingElement>
1228 _EuclideanRingElement
1229 __gcd(_EuclideanRingElement __m, _EuclideanRingElement __n)
1230 {
1231 while (__n != 0)
1232 {
1233 _EuclideanRingElement __t = __m % __n;
1234 __m = __n;
1235 __n = __t;
1236 }
1237 return __m;
1238 }
1239
1240 inline namespace _V2
1241 {
1242
1243 /// This is a helper function for the rotate algorithm.
1244 template<typename _ForwardIterator>
1245 _ForwardIterator
1246 __rotate(_ForwardIterator __first,
1247 _ForwardIterator __middle,
1248 _ForwardIterator __last,
1249 forward_iterator_tag)
1250 {
1251 if (__first == __middle)
1252 return __last;
1253 else if (__last == __middle)
1254 return __first;
1255
1256 _ForwardIterator __first2 = __middle;
1257 do
1258 {
1259 std::iter_swap(__first, __first2);
1260 ++__first;
1261 ++__first2;
1262 if (__first == __middle)
1263 __middle = __first2;
1264 }
1265 while (__first2 != __last);
1266
1267 _ForwardIterator __ret = __first;
1268
1269 __first2 = __middle;
1270
1271 while (__first2 != __last)
1272 {
1273 std::iter_swap(__first, __first2);
1274 ++__first;
1275 ++__first2;
1276 if (__first == __middle)
1277 __middle = __first2;
1278 else if (__first2 == __last)
1279 __first2 = __middle;
1280 }
1281 return __ret;
1282 }
1283
1284 /// This is a helper function for the rotate algorithm.
1285 template<typename _BidirectionalIterator>
1286 _BidirectionalIterator
1287 __rotate(_BidirectionalIterator __first,
1288 _BidirectionalIterator __middle,
1289 _BidirectionalIterator __last,
1290 bidirectional_iterator_tag)
1291 {
1292 // concept requirements
1293 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
1294 _BidirectionalIterator>)
1295
1296 if (__first == __middle)
1297 return __last;
1298 else if (__last == __middle)
1299 return __first;
1300
1301 std::__reverse(__first, __middle, bidirectional_iterator_tag());
1302 std::__reverse(__middle, __last, bidirectional_iterator_tag());
1303
1304 while (__first != __middle && __middle != __last)
1305 {
1306 std::iter_swap(__first, --__last);
1307 ++__first;
1308 }
1309
1310 if (__first == __middle)
1311 {
1312 std::__reverse(__middle, __last, bidirectional_iterator_tag());
1313 return __last;
1314 }
1315 else
1316 {
1317 std::__reverse(__first, __middle, bidirectional_iterator_tag());
1318 return __first;
1319 }
1320 }
1321
1322 /// This is a helper function for the rotate algorithm.
1323 template<typename _RandomAccessIterator>
1324 _RandomAccessIterator
1325 __rotate(_RandomAccessIterator __first,
1326 _RandomAccessIterator __middle,
1327 _RandomAccessIterator __last,
1328 random_access_iterator_tag)
1329 {
1330 // concept requirements
1331 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
1332 _RandomAccessIterator>)
1333
1334 if (__first == __middle)
1335 return __last;
1336 else if (__last == __middle)
1337 return __first;
1338
1339 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
1340 _Distance;
1341 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1342 _ValueType;
1343
1344 _Distance __n = __last - __first;
1345 _Distance __k = __middle - __first;
1346
1347 if (__k == __n - __k)
1348 {
1349 std::swap_ranges(__first, __middle, __middle);
1350 return __middle;
1351 }
1352
1353 _RandomAccessIterator __p = __first;
1354 _RandomAccessIterator __ret = __first + (__last - __middle);
1355
1356 for (;;)
1357 {
1358 if (__k < __n - __k)
1359 {
1360 if (__is_pod(_ValueType) && __k == 1)
1361 {
1362 _ValueType __t = _GLIBCXX_MOVE(*__p);
1363 _GLIBCXX_MOVE3(__p + 1, __p + __n, __p);
1364 *(__p + __n - 1) = _GLIBCXX_MOVE(__t);
1365 return __ret;
1366 }
1367 _RandomAccessIterator __q = __p + __k;
1368 for (_Distance __i = 0; __i < __n - __k; ++ __i)
1369 {
1370 std::iter_swap(__p, __q);
1371 ++__p;
1372 ++__q;
1373 }
1374 __n %= __k;
1375 if (__n == 0)
1376 return __ret;
1377 std::swap(__n, __k);
1378 __k = __n - __k;
1379 }
1380 else
1381 {
1382 __k = __n - __k;
1383 if (__is_pod(_ValueType) && __k == 1)
1384 {
1385 _ValueType __t = _GLIBCXX_MOVE(*(__p + __n - 1));
1386 _GLIBCXX_MOVE_BACKWARD3(__p, __p + __n - 1, __p + __n);
1387 *__p = _GLIBCXX_MOVE(__t);
1388 return __ret;
1389 }
1390 _RandomAccessIterator __q = __p + __n;
1391 __p = __q - __k;
1392 for (_Distance __i = 0; __i < __n - __k; ++ __i)
1393 {
1394 --__p;
1395 --__q;
1396 std::iter_swap(__p, __q);
1397 }
1398 __n %= __k;
1399 if (__n == 0)
1400 return __ret;
1401 std::swap(__n, __k);
1402 }
1403 }
1404 }
1405
1406 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1407 // DR 488. rotate throws away useful information
1408 /**
1409 * @brief Rotate the elements of a sequence.
1410 * @ingroup mutating_algorithms
1411 * @param __first A forward iterator.
1412 * @param __middle A forward iterator.
1413 * @param __last A forward iterator.
1414 * @return first + (last - middle).
1415 *
1416 * Rotates the elements of the range @p [__first,__last) by
1417 * @p (__middle - __first) positions so that the element at @p __middle
1418 * is moved to @p __first, the element at @p __middle+1 is moved to
1419 * @p __first+1 and so on for each element in the range
1420 * @p [__first,__last).
1421 *
1422 * This effectively swaps the ranges @p [__first,__middle) and
1423 * @p [__middle,__last).
1424 *
1425 * Performs
1426 * @p *(__first+(n+(__last-__middle))%(__last-__first))=*(__first+n)
1427 * for each @p n in the range @p [0,__last-__first).
1428 */
1429 template<typename _ForwardIterator>
1430 inline _ForwardIterator
1431 rotate(_ForwardIterator __first, _ForwardIterator __middle,
1432 _ForwardIterator __last)
1433 {
1434 // concept requirements
1435 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
1436 _ForwardIterator>)
1437 __glibcxx_requires_valid_range(__first, __middle);
1438 __glibcxx_requires_valid_range(__middle, __last);
1439
1440 return std::__rotate(__first, __middle, __last,
1441 std::__iterator_category(__first));
1442 }
1443
1444 } // namespace _V2
1445
1446 /**
1447 * @brief Copy a sequence, rotating its elements.
1448 * @ingroup mutating_algorithms
1449 * @param __first A forward iterator.
1450 * @param __middle A forward iterator.
1451 * @param __last A forward iterator.
1452 * @param __result An output iterator.
1453 * @return An iterator designating the end of the resulting sequence.
1454 *
1455 * Copies the elements of the range @p [__first,__last) to the
1456 * range beginning at @result, rotating the copied elements by
1457 * @p (__middle-__first) positions so that the element at @p __middle
1458 * is moved to @p __result, the element at @p __middle+1 is moved
1459 * to @p __result+1 and so on for each element in the range @p
1460 * [__first,__last).
1461 *
1462 * Performs
1463 * @p *(__result+(n+(__last-__middle))%(__last-__first))=*(__first+n)
1464 * for each @p n in the range @p [0,__last-__first).
1465 */
1466 template<typename _ForwardIterator, typename _OutputIterator>
1467 inline _OutputIterator
1468 rotate_copy(_ForwardIterator __first, _ForwardIterator __middle,
1469 _ForwardIterator __last, _OutputIterator __result)
1470 {
1471 // concept requirements
1472 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1473 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
1474 typename iterator_traits<_ForwardIterator>::value_type>)
1475 __glibcxx_requires_valid_range(__first, __middle);
1476 __glibcxx_requires_valid_range(__middle, __last);
1477
1478 return std::copy(__first, __middle,
1479 std::copy(__middle, __last, __result));
1480 }
1481
1482 /// This is a helper function...
1483 template<typename _ForwardIterator, typename _Predicate>
1484 _ForwardIterator
1485 __partition(_ForwardIterator __first, _ForwardIterator __last,
1486 _Predicate __pred, forward_iterator_tag)
1487 {
1488 if (__first == __last)
1489 return __first;
1490
1491 while (__pred(*__first))
1492 if (++__first == __last)
1493 return __first;
1494
1495 _ForwardIterator __next = __first;
1496
1497 while (++__next != __last)
1498 if (__pred(*__next))
1499 {
1500 std::iter_swap(__first, __next);
1501 ++__first;
1502 }
1503
1504 return __first;
1505 }
1506
1507 /// This is a helper function...
1508 template<typename _BidirectionalIterator, typename _Predicate>
1509 _BidirectionalIterator
1510 __partition(_BidirectionalIterator __first, _BidirectionalIterator __last,
1511 _Predicate __pred, bidirectional_iterator_tag)
1512 {
1513 while (true)
1514 {
1515 while (true)
1516 if (__first == __last)
1517 return __first;
1518 else if (__pred(*__first))
1519 ++__first;
1520 else
1521 break;
1522 --__last;
1523 while (true)
1524 if (__first == __last)
1525 return __first;
1526 else if (!bool(__pred(*__last)))
1527 --__last;
1528 else
1529 break;
1530 std::iter_swap(__first, __last);
1531 ++__first;
1532 }
1533 }
1534
1535 // partition
1536
1537 /// This is a helper function...
1538 /// Requires __first != __last and !__pred(__first)
1539 /// and __len == distance(__first, __last).
1540 ///
1541 /// !__pred(__first) allows us to guarantee that we don't
1542 /// move-assign an element onto itself.
1543 template<typename _ForwardIterator, typename _Pointer, typename _Predicate,
1544 typename _Distance>
1545 _ForwardIterator
1546 __stable_partition_adaptive(_ForwardIterator __first,
1547 _ForwardIterator __last,
1548 _Predicate __pred, _Distance __len,
1549 _Pointer __buffer,
1550 _Distance __buffer_size)
1551 {
1552 if (__len == 1)
1553 return __first;
1554
1555 if (__len <= __buffer_size)
1556 {
1557 _ForwardIterator __result1 = __first;
1558 _Pointer __result2 = __buffer;
1559
1560 // The precondition guarantees that !__pred(__first), so
1561 // move that element to the buffer before starting the loop.
1562 // This ensures that we only call __pred once per element.
1563 *__result2 = _GLIBCXX_MOVE(*__first);
1564 ++__result2;
1565 ++__first;
1566 for (; __first != __last; ++__first)
1567 if (__pred(__first))
1568 {
1569 *__result1 = _GLIBCXX_MOVE(*__first);
1570 ++__result1;
1571 }
1572 else
1573 {
1574 *__result2 = _GLIBCXX_MOVE(*__first);
1575 ++__result2;
1576 }
1577
1578 _GLIBCXX_MOVE3(__buffer, __result2, __result1);
1579 return __result1;
1580 }
1581
1582 _ForwardIterator __middle = __first;
1583 std::advance(__middle, __len / 2);
1584 _ForwardIterator __left_split =
1585 std::__stable_partition_adaptive(__first, __middle, __pred,
1586 __len / 2, __buffer,
1587 __buffer_size);
1588
1589 // Advance past true-predicate values to satisfy this
1590 // function's preconditions.
1591 _Distance __right_len = __len - __len / 2;
1592 _ForwardIterator __right_split =
1593 std::__find_if_not_n(__middle, __right_len, __pred);
1594
1595 if (__right_len)
1596 __right_split =
1597 std::__stable_partition_adaptive(__right_split, __last, __pred,
1598 __right_len,
1599 __buffer, __buffer_size);
1600
1601 std::rotate(__left_split, __middle, __right_split);
1602 std::advance(__left_split, std::distance(__middle, __right_split));
1603 return __left_split;
1604 }
1605
1606 template<typename _ForwardIterator, typename _Predicate>
1607 _ForwardIterator
1608 __stable_partition(_ForwardIterator __first, _ForwardIterator __last,
1609 _Predicate __pred)
1610 {
1611 __first = std::__find_if_not(__first, __last, __pred);
1612
1613 if (__first == __last)
1614 return __first;
1615
1616 typedef typename iterator_traits<_ForwardIterator>::value_type
1617 _ValueType;
1618 typedef typename iterator_traits<_ForwardIterator>::difference_type
1619 _DistanceType;
1620
1621 _Temporary_buffer<_ForwardIterator, _ValueType> __buf(__first, __last);
1622 return
1623 std::__stable_partition_adaptive(__first, __last, __pred,
1624 _DistanceType(__buf.requested_size()),
1625 __buf.begin(),
1626 _DistanceType(__buf.size()));
1627 }
1628
1629 /**
1630 * @brief Move elements for which a predicate is true to the beginning
1631 * of a sequence, preserving relative ordering.
1632 * @ingroup mutating_algorithms
1633 * @param __first A forward iterator.
1634 * @param __last A forward iterator.
1635 * @param __pred A predicate functor.
1636 * @return An iterator @p middle such that @p __pred(i) is true for each
1637 * iterator @p i in the range @p [first,middle) and false for each @p i
1638 * in the range @p [middle,last).
1639 *
1640 * Performs the same function as @p partition() with the additional
1641 * guarantee that the relative ordering of elements in each group is
1642 * preserved, so any two elements @p x and @p y in the range
1643 * @p [__first,__last) such that @p __pred(x)==__pred(y) will have the same
1644 * relative ordering after calling @p stable_partition().
1645 */
1646 template<typename _ForwardIterator, typename _Predicate>
1647 inline _ForwardIterator
1648 stable_partition(_ForwardIterator __first, _ForwardIterator __last,
1649 _Predicate __pred)
1650 {
1651 // concept requirements
1652 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
1653 _ForwardIterator>)
1654 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
1655 typename iterator_traits<_ForwardIterator>::value_type>)
1656 __glibcxx_requires_valid_range(__first, __last);
1657
1658 return std::__stable_partition(__first, __last,
1659 __gnu_cxx::__ops::__pred_iter(__pred));
1660 }
1661
1662 /// This is a helper function for the sort routines.
1663 template<typename _RandomAccessIterator, typename _Compare>
1664 void
1665 __heap_select(_RandomAccessIterator __first,
1666 _RandomAccessIterator __middle,
1667 _RandomAccessIterator __last, _Compare __comp)
1668 {
1669 std::__make_heap(__first, __middle, __comp);
1670 for (_RandomAccessIterator __i = __middle; __i < __last; ++__i)
1671 if (__comp(__i, __first))
1672 std::__pop_heap(__first, __middle, __i, __comp);
1673 }
1674
1675 // partial_sort
1676
1677 template<typename _InputIterator, typename _RandomAccessIterator,
1678 typename _Compare>
1679 _RandomAccessIterator
1680 __partial_sort_copy(_InputIterator __first, _InputIterator __last,
1681 _RandomAccessIterator __result_first,
1682 _RandomAccessIterator __result_last,
1683 _Compare __comp)
1684 {
1685 typedef typename iterator_traits<_InputIterator>::value_type
1686 _InputValueType;
1687 typedef iterator_traits<_RandomAccessIterator> _RItTraits;
1688 typedef typename _RItTraits::difference_type _DistanceType;
1689
1690 if (__result_first == __result_last)
1691 return __result_last;
1692 _RandomAccessIterator __result_real_last = __result_first;
1693 while (__first != __last && __result_real_last != __result_last)
1694 {
1695 *__result_real_last = *__first;
1696 ++__result_real_last;
1697 ++__first;
1698 }
1699
1700 std::__make_heap(__result_first, __result_real_last, __comp);
1701 while (__first != __last)
1702 {
1703 if (__comp(__first, __result_first))
1704 std::__adjust_heap(__result_first, _DistanceType(0),
1705 _DistanceType(__result_real_last
1706 - __result_first),
1707 _InputValueType(*__first), __comp);
1708 ++__first;
1709 }
1710 std::__sort_heap(__result_first, __result_real_last, __comp);
1711 return __result_real_last;
1712 }
1713
1714 /**
1715 * @brief Copy the smallest elements of a sequence.
1716 * @ingroup sorting_algorithms
1717 * @param __first An iterator.
1718 * @param __last Another iterator.
1719 * @param __result_first A random-access iterator.
1720 * @param __result_last Another random-access iterator.
1721 * @return An iterator indicating the end of the resulting sequence.
1722 *
1723 * Copies and sorts the smallest N values from the range @p [__first,__last)
1724 * to the range beginning at @p __result_first, where the number of
1725 * elements to be copied, @p N, is the smaller of @p (__last-__first) and
1726 * @p (__result_last-__result_first).
1727 * After the sort if @e i and @e j are iterators in the range
1728 * @p [__result_first,__result_first+N) such that i precedes j then
1729 * *j<*i is false.
1730 * The value returned is @p __result_first+N.
1731 */
1732 template<typename _InputIterator, typename _RandomAccessIterator>
1733 inline _RandomAccessIterator
1734 partial_sort_copy(_InputIterator __first, _InputIterator __last,
1735 _RandomAccessIterator __result_first,
1736 _RandomAccessIterator __result_last)
1737 {
1738 #ifdef _GLIBCXX_CONCEPT_CHECKS
1739 typedef typename iterator_traits<_InputIterator>::value_type
1740 _InputValueType;
1741 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1742 _OutputValueType;
1743 #endif
1744
1745 // concept requirements
1746 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
1747 __glibcxx_function_requires(_ConvertibleConcept<_InputValueType,
1748 _OutputValueType>)
1749 __glibcxx_function_requires(_LessThanOpConcept<_InputValueType,
1750 _OutputValueType>)
1751 __glibcxx_function_requires(_LessThanComparableConcept<_OutputValueType>)
1752 __glibcxx_requires_valid_range(__first, __last);
1753 __glibcxx_requires_irreflexive(__first, __last);
1754 __glibcxx_requires_valid_range(__result_first, __result_last);
1755
1756 return std::__partial_sort_copy(__first, __last,
1757 __result_first, __result_last,
1758 __gnu_cxx::__ops::__iter_less_iter());
1759 }
1760
1761 /**
1762 * @brief Copy the smallest elements of a sequence using a predicate for
1763 * comparison.
1764 * @ingroup sorting_algorithms
1765 * @param __first An input iterator.
1766 * @param __last Another input iterator.
1767 * @param __result_first A random-access iterator.
1768 * @param __result_last Another random-access iterator.
1769 * @param __comp A comparison functor.
1770 * @return An iterator indicating the end of the resulting sequence.
1771 *
1772 * Copies and sorts the smallest N values from the range @p [__first,__last)
1773 * to the range beginning at @p result_first, where the number of
1774 * elements to be copied, @p N, is the smaller of @p (__last-__first) and
1775 * @p (__result_last-__result_first).
1776 * After the sort if @e i and @e j are iterators in the range
1777 * @p [__result_first,__result_first+N) such that i precedes j then
1778 * @p __comp(*j,*i) is false.
1779 * The value returned is @p __result_first+N.
1780 */
1781 template<typename _InputIterator, typename _RandomAccessIterator,
1782 typename _Compare>
1783 inline _RandomAccessIterator
1784 partial_sort_copy(_InputIterator __first, _InputIterator __last,
1785 _RandomAccessIterator __result_first,
1786 _RandomAccessIterator __result_last,
1787 _Compare __comp)
1788 {
1789 #ifdef _GLIBCXX_CONCEPT_CHECKS
1790 typedef typename iterator_traits<_InputIterator>::value_type
1791 _InputValueType;
1792 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1793 _OutputValueType;
1794 #endif
1795
1796 // concept requirements
1797 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
1798 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
1799 _RandomAccessIterator>)
1800 __glibcxx_function_requires(_ConvertibleConcept<_InputValueType,
1801 _OutputValueType>)
1802 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
1803 _InputValueType, _OutputValueType>)
1804 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
1805 _OutputValueType, _OutputValueType>)
1806 __glibcxx_requires_valid_range(__first, __last);
1807 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
1808 __glibcxx_requires_valid_range(__result_first, __result_last);
1809
1810 return std::__partial_sort_copy(__first, __last,
1811 __result_first, __result_last,
1812 __gnu_cxx::__ops::__iter_comp_iter(__comp));
1813 }
1814
1815 /// This is a helper function for the sort routine.
1816 template<typename _RandomAccessIterator, typename _Compare>
1817 void
1818 __unguarded_linear_insert(_RandomAccessIterator __last,
1819 _Compare __comp)
1820 {
1821 typename iterator_traits<_RandomAccessIterator>::value_type
1822 __val = _GLIBCXX_MOVE(*__last);
1823 _RandomAccessIterator __next = __last;
1824 --__next;
1825 while (__comp(__val, __next))
1826 {
1827 *__last = _GLIBCXX_MOVE(*__next);
1828 __last = __next;
1829 --__next;
1830 }
1831 *__last = _GLIBCXX_MOVE(__val);
1832 }
1833
1834 /// This is a helper function for the sort routine.
1835 template<typename _RandomAccessIterator, typename _Compare>
1836 void
1837 __insertion_sort(_RandomAccessIterator __first,
1838 _RandomAccessIterator __last, _Compare __comp)
1839 {
1840 if (__first == __last) return;
1841
1842 for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
1843 {
1844 if (__comp(__i, __first))
1845 {
1846 typename iterator_traits<_RandomAccessIterator>::value_type
1847 __val = _GLIBCXX_MOVE(*__i);
1848 _GLIBCXX_MOVE_BACKWARD3(__first, __i, __i + 1);
1849 *__first = _GLIBCXX_MOVE(__val);
1850 }
1851 else
1852 std::__unguarded_linear_insert(__i,
1853 __gnu_cxx::__ops::__val_comp_iter(__comp));
1854 }
1855 }
1856
1857 /// This is a helper function for the sort routine.
1858 template<typename _RandomAccessIterator, typename _Compare>
1859 inline void
1860 __unguarded_insertion_sort(_RandomAccessIterator __first,
1861 _RandomAccessIterator __last, _Compare __comp)
1862 {
1863 for (_RandomAccessIterator __i = __first; __i != __last; ++__i)
1864 std::__unguarded_linear_insert(__i,
1865 __gnu_cxx::__ops::__val_comp_iter(__comp));
1866 }
1867
1868 /**
1869 * @doctodo
1870 * This controls some aspect of the sort routines.
1871 */
1872 enum { _S_threshold = 16 };
1873
1874 /// This is a helper function for the sort routine.
1875 template<typename _RandomAccessIterator, typename _Compare>
1876 void
1877 __final_insertion_sort(_RandomAccessIterator __first,
1878 _RandomAccessIterator __last, _Compare __comp)
1879 {
1880 if (__last - __first > int(_S_threshold))
1881 {
1882 std::__insertion_sort(__first, __first + int(_S_threshold), __comp);
1883 std::__unguarded_insertion_sort(__first + int(_S_threshold), __last,
1884 __comp);
1885 }
1886 else
1887 std::__insertion_sort(__first, __last, __comp);
1888 }
1889
1890 /// This is a helper function...
1891 template<typename _RandomAccessIterator, typename _Compare>
1892 _RandomAccessIterator
1893 __unguarded_partition(_RandomAccessIterator __first,
1894 _RandomAccessIterator __last,
1895 _RandomAccessIterator __pivot, _Compare __comp)
1896 {
1897 while (true)
1898 {
1899 while (__comp(__first, __pivot))
1900 ++__first;
1901 --__last;
1902 while (__comp(__pivot, __last))
1903 --__last;
1904 if (!(__first < __last))
1905 return __first;
1906 std::iter_swap(__first, __last);
1907 ++__first;
1908 }
1909 }
1910
1911 /// This is a helper function...
1912 template<typename _RandomAccessIterator, typename _Compare>
1913 inline _RandomAccessIterator
1914 __unguarded_partition_pivot(_RandomAccessIterator __first,
1915 _RandomAccessIterator __last, _Compare __comp)
1916 {
1917 _RandomAccessIterator __mid = __first + (__last - __first) / 2;
1918 std::__move_median_to_first(__first, __first + 1, __mid, __last - 1,
1919 __comp);
1920 return std::__unguarded_partition(__first + 1, __last, __first, __comp);
1921 }
1922
1923 template<typename _RandomAccessIterator, typename _Compare>
1924 inline void
1925 __partial_sort(_RandomAccessIterator __first,
1926 _RandomAccessIterator __middle,
1927 _RandomAccessIterator __last,
1928 _Compare __comp)
1929 {
1930 std::__heap_select(__first, __middle, __last, __comp);
1931 std::__sort_heap(__first, __middle, __comp);
1932 }
1933
1934 /// This is a helper function for the sort routine.
1935 template<typename _RandomAccessIterator, typename _Size, typename _Compare>
1936 void
1937 __introsort_loop(_RandomAccessIterator __first,
1938 _RandomAccessIterator __last,
1939 _Size __depth_limit, _Compare __comp)
1940 {
1941 while (__last - __first > int(_S_threshold))
1942 {
1943 if (__depth_limit == 0)
1944 {
1945 std::__partial_sort(__first, __last, __last, __comp);
1946 return;
1947 }
1948 --__depth_limit;
1949 _RandomAccessIterator __cut =
1950 std::__unguarded_partition_pivot(__first, __last, __comp);
1951 std::__introsort_loop(__cut, __last, __depth_limit, __comp);
1952 __last = __cut;
1953 }
1954 }
1955
1956 // sort
1957
1958 template<typename _RandomAccessIterator, typename _Compare>
1959 inline void
1960 __sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
1961 _Compare __comp)
1962 {
1963 if (__first != __last)
1964 {
1965 std::__introsort_loop(__first, __last,
1966 std::__lg(__last - __first) * 2,
1967 __comp);
1968 std::__final_insertion_sort(__first, __last, __comp);
1969 }
1970 }
1971
1972 template<typename _RandomAccessIterator, typename _Size, typename _Compare>
1973 void
1974 __introselect(_RandomAccessIterator __first, _RandomAccessIterator __nth,
1975 _RandomAccessIterator __last, _Size __depth_limit,
1976 _Compare __comp)
1977 {
1978 while (__last - __first > 3)
1979 {
1980 if (__depth_limit == 0)
1981 {
1982 std::__heap_select(__first, __nth + 1, __last, __comp);
1983 // Place the nth largest element in its final position.
1984 std::iter_swap(__first, __nth);
1985 return;
1986 }
1987 --__depth_limit;
1988 _RandomAccessIterator __cut =
1989 std::__unguarded_partition_pivot(__first, __last, __comp);
1990 if (__cut <= __nth)
1991 __first = __cut;
1992 else
1993 __last = __cut;
1994 }
1995 std::__insertion_sort(__first, __last, __comp);
1996 }
1997
1998 // nth_element
1999
2000 // lower_bound moved to stl_algobase.h
2001
2002 /**
2003 * @brief Finds the first position in which @p __val could be inserted
2004 * without changing the ordering.
2005 * @ingroup binary_search_algorithms
2006 * @param __first An iterator.
2007 * @param __last Another iterator.
2008 * @param __val The search term.
2009 * @param __comp A functor to use for comparisons.
2010 * @return An iterator pointing to the first element <em>not less
2011 * than</em> @p __val, or end() if every element is less
2012 * than @p __val.
2013 * @ingroup binary_search_algorithms
2014 *
2015 * The comparison function should have the same effects on ordering as
2016 * the function used for the initial sort.
2017 */
2018 template<typename _ForwardIterator, typename _Tp, typename _Compare>
2019 inline _ForwardIterator
2020 lower_bound(_ForwardIterator __first, _ForwardIterator __last,
2021 const _Tp& __val, _Compare __comp)
2022 {
2023 // concept requirements
2024 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2025 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2026 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
2027 __glibcxx_requires_partitioned_lower_pred(__first, __last,
2028 __val, __comp);
2029
2030 return std::__lower_bound(__first, __last, __val,
2031 __gnu_cxx::__ops::__iter_comp_val(__comp));
2032 }
2033
2034 template<typename _ForwardIterator, typename _Tp, typename _Compare>
2035 _ForwardIterator
2036 __upper_bound(_ForwardIterator __first, _ForwardIterator __last,
2037 const _Tp& __val, _Compare __comp)
2038 {
2039 typedef typename iterator_traits<_ForwardIterator>::difference_type
2040 _DistanceType;
2041
2042 _DistanceType __len = std::distance(__first, __last);
2043
2044 while (__len > 0)
2045 {
2046 _DistanceType __half = __len >> 1;
2047 _ForwardIterator __middle = __first;
2048 std::advance(__middle, __half);
2049 if (__comp(__val, __middle))
2050 __len = __half;
2051 else
2052 {
2053 __first = __middle;
2054 ++__first;
2055 __len = __len - __half - 1;
2056 }
2057 }
2058 return __first;
2059 }
2060
2061 /**
2062 * @brief Finds the last position in which @p __val could be inserted
2063 * without changing the ordering.
2064 * @ingroup binary_search_algorithms
2065 * @param __first An iterator.
2066 * @param __last Another iterator.
2067 * @param __val The search term.
2068 * @return An iterator pointing to the first element greater than @p __val,
2069 * or end() if no elements are greater than @p __val.
2070 * @ingroup binary_search_algorithms
2071 */
2072 template<typename _ForwardIterator, typename _Tp>
2073 inline _ForwardIterator
2074 upper_bound(_ForwardIterator __first, _ForwardIterator __last,
2075 const _Tp& __val)
2076 {
2077 // concept requirements
2078 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2079 __glibcxx_function_requires(_LessThanOpConcept<
2080 _Tp, typename iterator_traits<_ForwardIterator>::value_type>)
2081 __glibcxx_requires_partitioned_upper(__first, __last, __val);
2082
2083 return std::__upper_bound(__first, __last, __val,
2084 __gnu_cxx::__ops::__val_less_iter());
2085 }
2086
2087 /**
2088 * @brief Finds the last position in which @p __val could be inserted
2089 * without changing the ordering.
2090 * @ingroup binary_search_algorithms
2091 * @param __first An iterator.
2092 * @param __last Another iterator.
2093 * @param __val The search term.
2094 * @param __comp A functor to use for comparisons.
2095 * @return An iterator pointing to the first element greater than @p __val,
2096 * or end() if no elements are greater than @p __val.
2097 * @ingroup binary_search_algorithms
2098 *
2099 * The comparison function should have the same effects on ordering as
2100 * the function used for the initial sort.
2101 */
2102 template<typename _ForwardIterator, typename _Tp, typename _Compare>
2103 inline _ForwardIterator
2104 upper_bound(_ForwardIterator __first, _ForwardIterator __last,
2105 const _Tp& __val, _Compare __comp)
2106 {
2107 // concept requirements
2108 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2109 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2110 _Tp, typename iterator_traits<_ForwardIterator>::value_type>)
2111 __glibcxx_requires_partitioned_upper_pred(__first, __last,
2112 __val, __comp);
2113
2114 return std::__upper_bound(__first, __last, __val,
2115 __gnu_cxx::__ops::__val_comp_iter(__comp));
2116 }
2117
2118 template<typename _ForwardIterator, typename _Tp,
2119 typename _CompareItTp, typename _CompareTpIt>
2120 pair<_ForwardIterator, _ForwardIterator>
2121 __equal_range(_ForwardIterator __first, _ForwardIterator __last,
2122 const _Tp& __val,
2123 _CompareItTp __comp_it_val, _CompareTpIt __comp_val_it)
2124 {
2125 typedef typename iterator_traits<_ForwardIterator>::difference_type
2126 _DistanceType;
2127
2128 _DistanceType __len = std::distance(__first, __last);
2129
2130 while (__len > 0)
2131 {
2132 _DistanceType __half = __len >> 1;
2133 _ForwardIterator __middle = __first;
2134 std::advance(__middle, __half);
2135 if (__comp_it_val(__middle, __val))
2136 {
2137 __first = __middle;
2138 ++__first;
2139 __len = __len - __half - 1;
2140 }
2141 else if (__comp_val_it(__val, __middle))
2142 __len = __half;
2143 else
2144 {
2145 _ForwardIterator __left
2146 = std::__lower_bound(__first, __middle, __val, __comp_it_val);
2147 std::advance(__first, __len);
2148 _ForwardIterator __right
2149 = std::__upper_bound(++__middle, __first, __val, __comp_val_it);
2150 return pair<_ForwardIterator, _ForwardIterator>(__left, __right);
2151 }
2152 }
2153 return pair<_ForwardIterator, _ForwardIterator>(__first, __first);
2154 }
2155
2156 /**
2157 * @brief Finds the largest subrange in which @p __val could be inserted
2158 * at any place in it without changing the ordering.
2159 * @ingroup binary_search_algorithms
2160 * @param __first An iterator.
2161 * @param __last Another iterator.
2162 * @param __val The search term.
2163 * @return An pair of iterators defining the subrange.
2164 * @ingroup binary_search_algorithms
2165 *
2166 * This is equivalent to
2167 * @code
2168 * std::make_pair(lower_bound(__first, __last, __val),
2169 * upper_bound(__first, __last, __val))
2170 * @endcode
2171 * but does not actually call those functions.
2172 */
2173 template<typename _ForwardIterator, typename _Tp>
2174 inline pair<_ForwardIterator, _ForwardIterator>
2175 equal_range(_ForwardIterator __first, _ForwardIterator __last,
2176 const _Tp& __val)
2177 {
2178 // concept requirements
2179 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2180 __glibcxx_function_requires(_LessThanOpConcept<
2181 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
2182 __glibcxx_function_requires(_LessThanOpConcept<
2183 _Tp, typename iterator_traits<_ForwardIterator>::value_type>)
2184 __glibcxx_requires_partitioned_lower(__first, __last, __val);
2185 __glibcxx_requires_partitioned_upper(__first, __last, __val);
2186
2187 return std::__equal_range(__first, __last, __val,
2188 __gnu_cxx::__ops::__iter_less_val(),
2189 __gnu_cxx::__ops::__val_less_iter());
2190 }
2191
2192 /**
2193 * @brief Finds the largest subrange in which @p __val could be inserted
2194 * at any place in it without changing the ordering.
2195 * @param __first An iterator.
2196 * @param __last Another iterator.
2197 * @param __val The search term.
2198 * @param __comp A functor to use for comparisons.
2199 * @return An pair of iterators defining the subrange.
2200 * @ingroup binary_search_algorithms
2201 *
2202 * This is equivalent to
2203 * @code
2204 * std::make_pair(lower_bound(__first, __last, __val, __comp),
2205 * upper_bound(__first, __last, __val, __comp))
2206 * @endcode
2207 * but does not actually call those functions.
2208 */
2209 template<typename _ForwardIterator, typename _Tp, typename _Compare>
2210 inline pair<_ForwardIterator, _ForwardIterator>
2211 equal_range(_ForwardIterator __first, _ForwardIterator __last,
2212 const _Tp& __val, _Compare __comp)
2213 {
2214 // concept requirements
2215 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2216 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2217 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
2218 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2219 _Tp, typename iterator_traits<_ForwardIterator>::value_type>)
2220 __glibcxx_requires_partitioned_lower_pred(__first, __last,
2221 __val, __comp);
2222 __glibcxx_requires_partitioned_upper_pred(__first, __last,
2223 __val, __comp);
2224
2225 return std::__equal_range(__first, __last, __val,
2226 __gnu_cxx::__ops::__iter_comp_val(__comp),
2227 __gnu_cxx::__ops::__val_comp_iter(__comp));
2228 }
2229
2230 /**
2231 * @brief Determines whether an element exists in a range.
2232 * @ingroup binary_search_algorithms
2233 * @param __first An iterator.
2234 * @param __last Another iterator.
2235 * @param __val The search term.
2236 * @return True if @p __val (or its equivalent) is in [@p
2237 * __first,@p __last ].
2238 *
2239 * Note that this does not actually return an iterator to @p __val. For
2240 * that, use std::find or a container's specialized find member functions.
2241 */
2242 template<typename _ForwardIterator, typename _Tp>
2243 bool
2244 binary_search(_ForwardIterator __first, _ForwardIterator __last,
2245 const _Tp& __val)
2246 {
2247 // concept requirements
2248 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2249 __glibcxx_function_requires(_LessThanOpConcept<
2250 _Tp, typename iterator_traits<_ForwardIterator>::value_type>)
2251 __glibcxx_requires_partitioned_lower(__first, __last, __val);
2252 __glibcxx_requires_partitioned_upper(__first, __last, __val);
2253
2254 _ForwardIterator __i
2255 = std::__lower_bound(__first, __last, __val,
2256 __gnu_cxx::__ops::__iter_less_val());
2257 return __i != __last && !(__val < *__i);
2258 }
2259
2260 /**
2261 * @brief Determines whether an element exists in a range.
2262 * @ingroup binary_search_algorithms
2263 * @param __first An iterator.
2264 * @param __last Another iterator.
2265 * @param __val The search term.
2266 * @param __comp A functor to use for comparisons.
2267 * @return True if @p __val (or its equivalent) is in @p [__first,__last].
2268 *
2269 * Note that this does not actually return an iterator to @p __val. For
2270 * that, use std::find or a container's specialized find member functions.
2271 *
2272 * The comparison function should have the same effects on ordering as
2273 * the function used for the initial sort.
2274 */
2275 template<typename _ForwardIterator, typename _Tp, typename _Compare>
2276 bool
2277 binary_search(_ForwardIterator __first, _ForwardIterator __last,
2278 const _Tp& __val, _Compare __comp)
2279 {
2280 // concept requirements
2281 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2282 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2283 _Tp, typename iterator_traits<_ForwardIterator>::value_type>)
2284 __glibcxx_requires_partitioned_lower_pred(__first, __last,
2285 __val, __comp);
2286 __glibcxx_requires_partitioned_upper_pred(__first, __last,
2287 __val, __comp);
2288
2289 _ForwardIterator __i
2290 = std::__lower_bound(__first, __last, __val,
2291 __gnu_cxx::__ops::__iter_comp_val(__comp));
2292 return __i != __last && !bool(__comp(__val, *__i));
2293 }
2294
2295 // merge
2296
2297 /// This is a helper function for the __merge_adaptive routines.
2298 template<typename _InputIterator1, typename _InputIterator2,
2299 typename _OutputIterator, typename _Compare>
2300 void
2301 __move_merge_adaptive(_InputIterator1 __first1, _InputIterator1 __last1,
2302 _InputIterator2 __first2, _InputIterator2 __last2,
2303 _OutputIterator __result, _Compare __comp)
2304 {
2305 while (__first1 != __last1 && __first2 != __last2)
2306 {
2307 if (__comp(__first2, __first1))
2308 {
2309 *__result = _GLIBCXX_MOVE(*__first2);
2310 ++__first2;
2311 }
2312 else
2313 {
2314 *__result = _GLIBCXX_MOVE(*__first1);
2315 ++__first1;
2316 }
2317 ++__result;
2318 }
2319 if (__first1 != __last1)
2320 _GLIBCXX_MOVE3(__first1, __last1, __result);
2321 }
2322
2323 /// This is a helper function for the __merge_adaptive routines.
2324 template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
2325 typename _BidirectionalIterator3, typename _Compare>
2326 void
2327 __move_merge_adaptive_backward(_BidirectionalIterator1 __first1,
2328 _BidirectionalIterator1 __last1,
2329 _BidirectionalIterator2 __first2,
2330 _BidirectionalIterator2 __last2,
2331 _BidirectionalIterator3 __result,
2332 _Compare __comp)
2333 {
2334 if (__first1 == __last1)
2335 {
2336 _GLIBCXX_MOVE_BACKWARD3(__first2, __last2, __result);
2337 return;
2338 }
2339 else if (__first2 == __last2)
2340 return;
2341
2342 --__last1;
2343 --__last2;
2344 while (true)
2345 {
2346 if (__comp(__last2, __last1))
2347 {
2348 *--__result = _GLIBCXX_MOVE(*__last1);
2349 if (__first1 == __last1)
2350 {
2351 _GLIBCXX_MOVE_BACKWARD3(__first2, ++__last2, __result);
2352 return;
2353 }
2354 --__last1;
2355 }
2356 else
2357 {
2358 *--__result = _GLIBCXX_MOVE(*__last2);
2359 if (__first2 == __last2)
2360 return;
2361 --__last2;
2362 }
2363 }
2364 }
2365
2366 /// This is a helper function for the merge routines.
2367 template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
2368 typename _Distance>
2369 _BidirectionalIterator1
2370 __rotate_adaptive(_BidirectionalIterator1 __first,
2371 _BidirectionalIterator1 __middle,
2372 _BidirectionalIterator1 __last,
2373 _Distance __len1, _Distance __len2,
2374 _BidirectionalIterator2 __buffer,
2375 _Distance __buffer_size)
2376 {
2377 _BidirectionalIterator2 __buffer_end;
2378 if (__len1 > __len2 && __len2 <= __buffer_size)
2379 {
2380 if (__len2)
2381 {
2382 __buffer_end = _GLIBCXX_MOVE3(__middle, __last, __buffer);
2383 _GLIBCXX_MOVE_BACKWARD3(__first, __middle, __last);
2384 return _GLIBCXX_MOVE3(__buffer, __buffer_end, __first);
2385 }
2386 else
2387 return __first;
2388 }
2389 else if (__len1 <= __buffer_size)
2390 {
2391 if (__len1)
2392 {
2393 __buffer_end = _GLIBCXX_MOVE3(__first, __middle, __buffer);
2394 _GLIBCXX_MOVE3(__middle, __last, __first);
2395 return _GLIBCXX_MOVE_BACKWARD3(__buffer, __buffer_end, __last);
2396 }
2397 else
2398 return __last;
2399 }
2400 else
2401 {
2402 std::rotate(__first, __middle, __last);
2403 std::advance(__first, std::distance(__middle, __last));
2404 return __first;
2405 }
2406 }
2407
2408 /// This is a helper function for the merge routines.
2409 template<typename _BidirectionalIterator, typename _Distance,
2410 typename _Pointer, typename _Compare>
2411 void
2412 __merge_adaptive(_BidirectionalIterator __first,
2413 _BidirectionalIterator __middle,
2414 _BidirectionalIterator __last,
2415 _Distance __len1, _Distance __len2,
2416 _Pointer __buffer, _Distance __buffer_size,
2417 _Compare __comp)
2418 {
2419 if (__len1 <= __len2 && __len1 <= __buffer_size)
2420 {
2421 _Pointer __buffer_end = _GLIBCXX_MOVE3(__first, __middle, __buffer);
2422 std::__move_merge_adaptive(__buffer, __buffer_end, __middle, __last,
2423 __first, __comp);
2424 }
2425 else if (__len2 <= __buffer_size)
2426 {
2427 _Pointer __buffer_end = _GLIBCXX_MOVE3(__middle, __last, __buffer);
2428 std::__move_merge_adaptive_backward(__first, __middle, __buffer,
2429 __buffer_end, __last, __comp);
2430 }
2431 else
2432 {
2433 _BidirectionalIterator __first_cut = __first;
2434 _BidirectionalIterator __second_cut = __middle;
2435 _Distance __len11 = 0;
2436 _Distance __len22 = 0;
2437 if (__len1 > __len2)
2438 {
2439 __len11 = __len1 / 2;
2440 std::advance(__first_cut, __len11);
2441 __second_cut
2442 = std::__lower_bound(__middle, __last, *__first_cut,
2443 __gnu_cxx::__ops::__iter_comp_val(__comp));
2444 __len22 = std::distance(__middle, __second_cut);
2445 }
2446 else
2447 {
2448 __len22 = __len2 / 2;
2449 std::advance(__second_cut, __len22);
2450 __first_cut
2451 = std::__upper_bound(__first, __middle, *__second_cut,
2452 __gnu_cxx::__ops::__val_comp_iter(__comp));
2453 __len11 = std::distance(__first, __first_cut);
2454 }
2455
2456 _BidirectionalIterator __new_middle
2457 = std::__rotate_adaptive(__first_cut, __middle, __second_cut,
2458 __len1 - __len11, __len22, __buffer,
2459 __buffer_size);
2460 std::__merge_adaptive(__first, __first_cut, __new_middle, __len11,
2461 __len22, __buffer, __buffer_size, __comp);
2462 std::__merge_adaptive(__new_middle, __second_cut, __last,
2463 __len1 - __len11,
2464 __len2 - __len22, __buffer,
2465 __buffer_size, __comp);
2466 }
2467 }
2468
2469 /// This is a helper function for the merge routines.
2470 template<typename _BidirectionalIterator, typename _Distance,
2471 typename _Compare>
2472 void
2473 __merge_without_buffer(_BidirectionalIterator __first,
2474 _BidirectionalIterator __middle,
2475 _BidirectionalIterator __last,
2476 _Distance __len1, _Distance __len2,
2477 _Compare __comp)
2478 {
2479 if (__len1 == 0 || __len2 == 0)
2480 return;
2481
2482 if (__len1 + __len2 == 2)
2483 {
2484 if (__comp(__middle, __first))
2485 std::iter_swap(__first, __middle);
2486 return;
2487 }
2488
2489 _BidirectionalIterator __first_cut = __first;
2490 _BidirectionalIterator __second_cut = __middle;
2491 _Distance __len11 = 0;
2492 _Distance __len22 = 0;
2493 if (__len1 > __len2)
2494 {
2495 __len11 = __len1 / 2;
2496 std::advance(__first_cut, __len11);
2497 __second_cut
2498 = std::__lower_bound(__middle, __last, *__first_cut,
2499 __gnu_cxx::__ops::__iter_comp_val(__comp));
2500 __len22 = std::distance(__middle, __second_cut);
2501 }
2502 else
2503 {
2504 __len22 = __len2 / 2;
2505 std::advance(__second_cut, __len22);
2506 __first_cut
2507 = std::__upper_bound(__first, __middle, *__second_cut,
2508 __gnu_cxx::__ops::__val_comp_iter(__comp));
2509 __len11 = std::distance(__first, __first_cut);
2510 }
2511
2512 std::rotate(__first_cut, __middle, __second_cut);
2513 _BidirectionalIterator __new_middle = __first_cut;
2514 std::advance(__new_middle, std::distance(__middle, __second_cut));
2515 std::__merge_without_buffer(__first, __first_cut, __new_middle,
2516 __len11, __len22, __comp);
2517 std::__merge_without_buffer(__new_middle, __second_cut, __last,
2518 __len1 - __len11, __len2 - __len22, __comp);
2519 }
2520
2521 template<typename _BidirectionalIterator, typename _Compare>
2522 void
2523 __inplace_merge(_BidirectionalIterator __first,
2524 _BidirectionalIterator __middle,
2525 _BidirectionalIterator __last,
2526 _Compare __comp)
2527 {
2528 typedef typename iterator_traits<_BidirectionalIterator>::value_type
2529 _ValueType;
2530 typedef typename iterator_traits<_BidirectionalIterator>::difference_type
2531 _DistanceType;
2532
2533 if (__first == __middle || __middle == __last)
2534 return;
2535
2536 const _DistanceType __len1 = std::distance(__first, __middle);
2537 const _DistanceType __len2 = std::distance(__middle, __last);
2538
2539 typedef _Temporary_buffer<_BidirectionalIterator, _ValueType> _TmpBuf;
2540 _TmpBuf __buf(__first, __last);
2541
2542 if (__buf.begin() == 0)
2543 std::__merge_without_buffer
2544 (__first, __middle, __last, __len1, __len2, __comp);
2545 else
2546 std::__merge_adaptive
2547 (__first, __middle, __last, __len1, __len2, __buf.begin(),
2548 _DistanceType(__buf.size()), __comp);
2549 }
2550
2551 /**
2552 * @brief Merges two sorted ranges in place.
2553 * @ingroup sorting_algorithms
2554 * @param __first An iterator.
2555 * @param __middle Another iterator.
2556 * @param __last Another iterator.
2557 * @return Nothing.
2558 *
2559 * Merges two sorted and consecutive ranges, [__first,__middle) and
2560 * [__middle,__last), and puts the result in [__first,__last). The
2561 * output will be sorted. The sort is @e stable, that is, for
2562 * equivalent elements in the two ranges, elements from the first
2563 * range will always come before elements from the second.
2564 *
2565 * If enough additional memory is available, this takes (__last-__first)-1
2566 * comparisons. Otherwise an NlogN algorithm is used, where N is
2567 * distance(__first,__last).
2568 */
2569 template<typename _BidirectionalIterator>
2570 inline void
2571 inplace_merge(_BidirectionalIterator __first,
2572 _BidirectionalIterator __middle,
2573 _BidirectionalIterator __last)
2574 {
2575 // concept requirements
2576 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
2577 _BidirectionalIterator>)
2578 __glibcxx_function_requires(_LessThanComparableConcept<
2579 typename iterator_traits<_BidirectionalIterator>::value_type>)
2580 __glibcxx_requires_sorted(__first, __middle);
2581 __glibcxx_requires_sorted(__middle, __last);
2582 __glibcxx_requires_irreflexive(__first, __last);
2583
2584 std::__inplace_merge(__first, __middle, __last,
2585 __gnu_cxx::__ops::__iter_less_iter());
2586 }
2587
2588 /**
2589 * @brief Merges two sorted ranges in place.
2590 * @ingroup sorting_algorithms
2591 * @param __first An iterator.
2592 * @param __middle Another iterator.
2593 * @param __last Another iterator.
2594 * @param __comp A functor to use for comparisons.
2595 * @return Nothing.
2596 *
2597 * Merges two sorted and consecutive ranges, [__first,__middle) and
2598 * [middle,last), and puts the result in [__first,__last). The output will
2599 * be sorted. The sort is @e stable, that is, for equivalent
2600 * elements in the two ranges, elements from the first range will always
2601 * come before elements from the second.
2602 *
2603 * If enough additional memory is available, this takes (__last-__first)-1
2604 * comparisons. Otherwise an NlogN algorithm is used, where N is
2605 * distance(__first,__last).
2606 *
2607 * The comparison function should have the same effects on ordering as
2608 * the function used for the initial sort.
2609 */
2610 template<typename _BidirectionalIterator, typename _Compare>
2611 inline void
2612 inplace_merge(_BidirectionalIterator __first,
2613 _BidirectionalIterator __middle,
2614 _BidirectionalIterator __last,
2615 _Compare __comp)
2616 {
2617 // concept requirements
2618 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
2619 _BidirectionalIterator>)
2620 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2621 typename iterator_traits<_BidirectionalIterator>::value_type,
2622 typename iterator_traits<_BidirectionalIterator>::value_type>)
2623 __glibcxx_requires_sorted_pred(__first, __middle, __comp);
2624 __glibcxx_requires_sorted_pred(__middle, __last, __comp);
2625 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
2626
2627 std::__inplace_merge(__first, __middle, __last,
2628 __gnu_cxx::__ops::__iter_comp_iter(__comp));
2629 }
2630
2631
2632 /// This is a helper function for the __merge_sort_loop routines.
2633 template<typename _InputIterator, typename _OutputIterator,
2634 typename _Compare>
2635 _OutputIterator
2636 __move_merge(_InputIterator __first1, _InputIterator __last1,
2637 _InputIterator __first2, _InputIterator __last2,
2638 _OutputIterator __result, _Compare __comp)
2639 {
2640 while (__first1 != __last1 && __first2 != __last2)
2641 {
2642 if (__comp(__first2, __first1))
2643 {
2644 *__result = _GLIBCXX_MOVE(*__first2);
2645 ++__first2;
2646 }
2647 else
2648 {
2649 *__result = _GLIBCXX_MOVE(*__first1);
2650 ++__first1;
2651 }
2652 ++__result;
2653 }
2654 return _GLIBCXX_MOVE3(__first2, __last2,
2655 _GLIBCXX_MOVE3(__first1, __last1,
2656 __result));
2657 }
2658
2659 template<typename _RandomAccessIterator1, typename _RandomAccessIterator2,
2660 typename _Distance, typename _Compare>
2661 void
2662 __merge_sort_loop(_RandomAccessIterator1 __first,
2663 _RandomAccessIterator1 __last,
2664 _RandomAccessIterator2 __result, _Distance __step_size,
2665 _Compare __comp)
2666 {
2667 const _Distance __two_step = 2 * __step_size;
2668
2669 while (__last - __first >= __two_step)
2670 {
2671 __result = std::__move_merge(__first, __first + __step_size,
2672 __first + __step_size,
2673 __first + __two_step,
2674 __result, __comp);
2675 __first += __two_step;
2676 }
2677 __step_size = std::min(_Distance(__last - __first), __step_size);
2678
2679 std::__move_merge(__first, __first + __step_size,
2680 __first + __step_size, __last, __result, __comp);
2681 }
2682
2683 template<typename _RandomAccessIterator, typename _Distance,
2684 typename _Compare>
2685 void
2686 __chunk_insertion_sort(_RandomAccessIterator __first,
2687 _RandomAccessIterator __last,
2688 _Distance __chunk_size, _Compare __comp)
2689 {
2690 while (__last - __first >= __chunk_size)
2691 {
2692 std::__insertion_sort(__first, __first + __chunk_size, __comp);
2693 __first += __chunk_size;
2694 }
2695 std::__insertion_sort(__first, __last, __comp);
2696 }
2697
2698 enum { _S_chunk_size = 7 };
2699
2700 template<typename _RandomAccessIterator, typename _Pointer, typename _Compare>
2701 void
2702 __merge_sort_with_buffer(_RandomAccessIterator __first,
2703 _RandomAccessIterator __last,
2704 _Pointer __buffer, _Compare __comp)
2705 {
2706 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
2707 _Distance;
2708
2709 const _Distance __len = __last - __first;
2710 const _Pointer __buffer_last = __buffer + __len;
2711
2712 _Distance __step_size = _S_chunk_size;
2713 std::__chunk_insertion_sort(__first, __last, __step_size, __comp);
2714
2715 while (__step_size < __len)
2716 {
2717 std::__merge_sort_loop(__first, __last, __buffer,
2718 __step_size, __comp);
2719 __step_size *= 2;
2720 std::__merge_sort_loop(__buffer, __buffer_last, __first,
2721 __step_size, __comp);
2722 __step_size *= 2;
2723 }
2724 }
2725
2726 template<typename _RandomAccessIterator, typename _Pointer,
2727 typename _Distance, typename _Compare>
2728 void
2729 __stable_sort_adaptive(_RandomAccessIterator __first,
2730 _RandomAccessIterator __last,
2731 _Pointer __buffer, _Distance __buffer_size,
2732 _Compare __comp)
2733 {
2734 const _Distance __len = (__last - __first + 1) / 2;
2735 const _RandomAccessIterator __middle = __first + __len;
2736 if (__len > __buffer_size)
2737 {
2738 std::__stable_sort_adaptive(__first, __middle, __buffer,
2739 __buffer_size, __comp);
2740 std::__stable_sort_adaptive(__middle, __last, __buffer,
2741 __buffer_size, __comp);
2742 }
2743 else
2744 {
2745 std::__merge_sort_with_buffer(__first, __middle, __buffer, __comp);
2746 std::__merge_sort_with_buffer(__middle, __last, __buffer, __comp);
2747 }
2748 std::__merge_adaptive(__first, __middle, __last,
2749 _Distance(__middle - __first),
2750 _Distance(__last - __middle),
2751 __buffer, __buffer_size,
2752 __comp);
2753 }
2754
2755 /// This is a helper function for the stable sorting routines.
2756 template<typename _RandomAccessIterator, typename _Compare>
2757 void
2758 __inplace_stable_sort(_RandomAccessIterator __first,
2759 _RandomAccessIterator __last, _Compare __comp)
2760 {
2761 if (__last - __first < 15)
2762 {
2763 std::__insertion_sort(__first, __last, __comp);
2764 return;
2765 }
2766 _RandomAccessIterator __middle = __first + (__last - __first) / 2;
2767 std::__inplace_stable_sort(__first, __middle, __comp);
2768 std::__inplace_stable_sort(__middle, __last, __comp);
2769 std::__merge_without_buffer(__first, __middle, __last,
2770 __middle - __first,
2771 __last - __middle,
2772 __comp);
2773 }
2774
2775 // stable_sort
2776
2777 // Set algorithms: includes, set_union, set_intersection, set_difference,
2778 // set_symmetric_difference. All of these algorithms have the precondition
2779 // that their input ranges are sorted and the postcondition that their output
2780 // ranges are sorted.
2781
2782 template<typename _InputIterator1, typename _InputIterator2,
2783 typename _Compare>
2784 bool
2785 __includes(_InputIterator1 __first1, _InputIterator1 __last1,
2786 _InputIterator2 __first2, _InputIterator2 __last2,
2787 _Compare __comp)
2788 {
2789 while (__first1 != __last1 && __first2 != __last2)
2790 if (__comp(__first2, __first1))
2791 return false;
2792 else if (__comp(__first1, __first2))
2793 ++__first1;
2794 else
2795 {
2796 ++__first1;
2797 ++__first2;
2798 }
2799
2800 return __first2 == __last2;
2801 }
2802
2803 /**
2804 * @brief Determines whether all elements of a sequence exists in a range.
2805 * @param __first1 Start of search range.
2806 * @param __last1 End of search range.
2807 * @param __first2 Start of sequence
2808 * @param __last2 End of sequence.
2809 * @return True if each element in [__first2,__last2) is contained in order
2810 * within [__first1,__last1). False otherwise.
2811 * @ingroup set_algorithms
2812 *
2813 * This operation expects both [__first1,__last1) and
2814 * [__first2,__last2) to be sorted. Searches for the presence of
2815 * each element in [__first2,__last2) within [__first1,__last1).
2816 * The iterators over each range only move forward, so this is a
2817 * linear algorithm. If an element in [__first2,__last2) is not
2818 * found before the search iterator reaches @p __last2, false is
2819 * returned.
2820 */
2821 template<typename _InputIterator1, typename _InputIterator2>
2822 inline bool
2823 includes(_InputIterator1 __first1, _InputIterator1 __last1,
2824 _InputIterator2 __first2, _InputIterator2 __last2)
2825 {
2826 // concept requirements
2827 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
2828 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
2829 __glibcxx_function_requires(_LessThanOpConcept<
2830 typename iterator_traits<_InputIterator1>::value_type,
2831 typename iterator_traits<_InputIterator2>::value_type>)
2832 __glibcxx_function_requires(_LessThanOpConcept<
2833 typename iterator_traits<_InputIterator2>::value_type,
2834 typename iterator_traits<_InputIterator1>::value_type>)
2835 __glibcxx_requires_sorted_set(__first1, __last1, __first2);
2836 __glibcxx_requires_sorted_set(__first2, __last2, __first1);
2837 __glibcxx_requires_irreflexive2(__first1, __last1);
2838 __glibcxx_requires_irreflexive2(__first2, __last2);
2839
2840 return std::__includes(__first1, __last1, __first2, __last2,
2841 __gnu_cxx::__ops::__iter_less_iter());
2842 }
2843
2844 /**
2845 * @brief Determines whether all elements of a sequence exists in a range
2846 * using comparison.
2847 * @ingroup set_algorithms
2848 * @param __first1 Start of search range.
2849 * @param __last1 End of search range.
2850 * @param __first2 Start of sequence
2851 * @param __last2 End of sequence.
2852 * @param __comp Comparison function to use.
2853 * @return True if each element in [__first2,__last2) is contained
2854 * in order within [__first1,__last1) according to comp. False
2855 * otherwise. @ingroup set_algorithms
2856 *
2857 * This operation expects both [__first1,__last1) and
2858 * [__first2,__last2) to be sorted. Searches for the presence of
2859 * each element in [__first2,__last2) within [__first1,__last1),
2860 * using comp to decide. The iterators over each range only move
2861 * forward, so this is a linear algorithm. If an element in
2862 * [__first2,__last2) is not found before the search iterator
2863 * reaches @p __last2, false is returned.
2864 */
2865 template<typename _InputIterator1, typename _InputIterator2,
2866 typename _Compare>
2867 inline bool
2868 includes(_InputIterator1 __first1, _InputIterator1 __last1,
2869 _InputIterator2 __first2, _InputIterator2 __last2,
2870 _Compare __comp)
2871 {
2872 // concept requirements
2873 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
2874 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
2875 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2876 typename iterator_traits<_InputIterator1>::value_type,
2877 typename iterator_traits<_InputIterator2>::value_type>)
2878 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2879 typename iterator_traits<_InputIterator2>::value_type,
2880 typename iterator_traits<_InputIterator1>::value_type>)
2881 __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
2882 __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
2883 __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
2884 __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
2885
2886 return std::__includes(__first1, __last1, __first2, __last2,
2887 __gnu_cxx::__ops::__iter_comp_iter(__comp));
2888 }
2889
2890 // nth_element
2891 // merge
2892 // set_difference
2893 // set_intersection
2894 // set_union
2895 // stable_sort
2896 // set_symmetric_difference
2897 // min_element
2898 // max_element
2899
2900 template<typename _BidirectionalIterator, typename _Compare>
2901 bool
2902 __next_permutation(_BidirectionalIterator __first,
2903 _BidirectionalIterator __last, _Compare __comp)
2904 {
2905 if (__first == __last)
2906 return false;
2907 _BidirectionalIterator __i = __first;
2908 ++__i;
2909 if (__i == __last)
2910 return false;
2911 __i = __last;
2912 --__i;
2913
2914 for(;;)
2915 {
2916 _BidirectionalIterator __ii = __i;
2917 --__i;
2918 if (__comp(__i, __ii))
2919 {
2920 _BidirectionalIterator __j = __last;
2921 while (!__comp(__i, --__j))
2922 {}
2923 std::iter_swap(__i, __j);
2924 std::__reverse(__ii, __last,
2925 std::__iterator_category(__first));
2926 return true;
2927 }
2928 if (__i == __first)
2929 {
2930 std::__reverse(__first, __last,
2931 std::__iterator_category(__first));
2932 return false;
2933 }
2934 }
2935 }
2936
2937 /**
2938 * @brief Permute range into the next @e dictionary ordering.
2939 * @ingroup sorting_algorithms
2940 * @param __first Start of range.
2941 * @param __last End of range.
2942 * @return False if wrapped to first permutation, true otherwise.
2943 *
2944 * Treats all permutations of the range as a set of @e dictionary sorted
2945 * sequences. Permutes the current sequence into the next one of this set.
2946 * Returns true if there are more sequences to generate. If the sequence
2947 * is the largest of the set, the smallest is generated and false returned.
2948 */
2949 template<typename _BidirectionalIterator>
2950 inline bool
2951 next_permutation(_BidirectionalIterator __first,
2952 _BidirectionalIterator __last)
2953 {
2954 // concept requirements
2955 __glibcxx_function_requires(_BidirectionalIteratorConcept<
2956 _BidirectionalIterator>)
2957 __glibcxx_function_requires(_LessThanComparableConcept<
2958 typename iterator_traits<_BidirectionalIterator>::value_type>)
2959 __glibcxx_requires_valid_range(__first, __last);
2960 __glibcxx_requires_irreflexive(__first, __last);
2961
2962 return std::__next_permutation
2963 (__first, __last, __gnu_cxx::__ops::__iter_less_iter());
2964 }
2965
2966 /**
2967 * @brief Permute range into the next @e dictionary ordering using
2968 * comparison functor.
2969 * @ingroup sorting_algorithms
2970 * @param __first Start of range.
2971 * @param __last End of range.
2972 * @param __comp A comparison functor.
2973 * @return False if wrapped to first permutation, true otherwise.
2974 *
2975 * Treats all permutations of the range [__first,__last) as a set of
2976 * @e dictionary sorted sequences ordered by @p __comp. Permutes the current
2977 * sequence into the next one of this set. Returns true if there are more
2978 * sequences to generate. If the sequence is the largest of the set, the
2979 * smallest is generated and false returned.
2980 */
2981 template<typename _BidirectionalIterator, typename _Compare>
2982 inline bool
2983 next_permutation(_BidirectionalIterator __first,
2984 _BidirectionalIterator __last, _Compare __comp)
2985 {
2986 // concept requirements
2987 __glibcxx_function_requires(_BidirectionalIteratorConcept<
2988 _BidirectionalIterator>)
2989 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2990 typename iterator_traits<_BidirectionalIterator>::value_type,
2991 typename iterator_traits<_BidirectionalIterator>::value_type>)
2992 __glibcxx_requires_valid_range(__first, __last);
2993 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
2994
2995 return std::__next_permutation
2996 (__first, __last, __gnu_cxx::__ops::__iter_comp_iter(__comp));
2997 }
2998
2999 template<typename _BidirectionalIterator, typename _Compare>
3000 bool
3001 __prev_permutation(_BidirectionalIterator __first,
3002 _BidirectionalIterator __last, _Compare __comp)
3003 {
3004 if (__first == __last)
3005 return false;
3006 _BidirectionalIterator __i = __first;
3007 ++__i;
3008 if (__i == __last)
3009 return false;
3010 __i = __last;
3011 --__i;
3012
3013 for(;;)
3014 {
3015 _BidirectionalIterator __ii = __i;
3016 --__i;
3017 if (__comp(__ii, __i))
3018 {
3019 _BidirectionalIterator __j = __last;
3020 while (!__comp(--__j, __i))
3021 {}
3022 std::iter_swap(__i, __j);
3023 std::__reverse(__ii, __last,
3024 std::__iterator_category(__first));
3025 return true;
3026 }
3027 if (__i == __first)
3028 {
3029 std::__reverse(__first, __last,
3030 std::__iterator_category(__first));
3031 return false;
3032 }
3033 }
3034 }
3035
3036 /**
3037 * @brief Permute range into the previous @e dictionary ordering.
3038 * @ingroup sorting_algorithms
3039 * @param __first Start of range.
3040 * @param __last End of range.
3041 * @return False if wrapped to last permutation, true otherwise.
3042 *
3043 * Treats all permutations of the range as a set of @e dictionary sorted
3044 * sequences. Permutes the current sequence into the previous one of this
3045 * set. Returns true if there are more sequences to generate. If the
3046 * sequence is the smallest of the set, the largest is generated and false
3047 * returned.
3048 */
3049 template<typename _BidirectionalIterator>
3050 inline bool
3051 prev_permutation(_BidirectionalIterator __first,
3052 _BidirectionalIterator __last)
3053 {
3054 // concept requirements
3055 __glibcxx_function_requires(_BidirectionalIteratorConcept<
3056 _BidirectionalIterator>)
3057 __glibcxx_function_requires(_LessThanComparableConcept<
3058 typename iterator_traits<_BidirectionalIterator>::value_type>)
3059 __glibcxx_requires_valid_range(__first, __last);
3060 __glibcxx_requires_irreflexive(__first, __last);
3061
3062 return std::__prev_permutation(__first, __last,
3063 __gnu_cxx::__ops::__iter_less_iter());
3064 }
3065
3066 /**
3067 * @brief Permute range into the previous @e dictionary ordering using
3068 * comparison functor.
3069 * @ingroup sorting_algorithms
3070 * @param __first Start of range.
3071 * @param __last End of range.
3072 * @param __comp A comparison functor.
3073 * @return False if wrapped to last permutation, true otherwise.
3074 *
3075 * Treats all permutations of the range [__first,__last) as a set of
3076 * @e dictionary sorted sequences ordered by @p __comp. Permutes the current
3077 * sequence into the previous one of this set. Returns true if there are
3078 * more sequences to generate. If the sequence is the smallest of the set,
3079 * the largest is generated and false returned.
3080 */
3081 template<typename _BidirectionalIterator, typename _Compare>
3082 inline bool
3083 prev_permutation(_BidirectionalIterator __first,
3084 _BidirectionalIterator __last, _Compare __comp)
3085 {
3086 // concept requirements
3087 __glibcxx_function_requires(_BidirectionalIteratorConcept<
3088 _BidirectionalIterator>)
3089 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
3090 typename iterator_traits<_BidirectionalIterator>::value_type,
3091 typename iterator_traits<_BidirectionalIterator>::value_type>)
3092 __glibcxx_requires_valid_range(__first, __last);
3093 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
3094
3095 return std::__prev_permutation(__first, __last,
3096 __gnu_cxx::__ops::__iter_comp_iter(__comp));
3097 }
3098
3099 // replace
3100 // replace_if
3101
3102 template<typename _InputIterator, typename _OutputIterator,
3103 typename _Predicate, typename _Tp>
3104 _OutputIterator
3105 __replace_copy_if(_InputIterator __first, _InputIterator __last,
3106 _OutputIterator __result,
3107 _Predicate __pred, const _Tp& __new_value)
3108 {
3109 for (; __first != __last; ++__first, (void)++__result)
3110 if (__pred(__first))
3111 *__result = __new_value;
3112 else
3113 *__result = *__first;
3114 return __result;
3115 }
3116
3117 /**
3118 * @brief Copy a sequence, replacing each element of one value with another
3119 * value.
3120 * @param __first An input iterator.
3121 * @param __last An input iterator.
3122 * @param __result An output iterator.
3123 * @param __old_value The value to be replaced.
3124 * @param __new_value The replacement value.
3125 * @return The end of the output sequence, @p result+(last-first).
3126 *
3127 * Copies each element in the input range @p [__first,__last) to the
3128 * output range @p [__result,__result+(__last-__first)) replacing elements
3129 * equal to @p __old_value with @p __new_value.
3130 */
3131 template<typename _InputIterator, typename _OutputIterator, typename _Tp>
3132 inline _OutputIterator
3133 replace_copy(_InputIterator __first, _InputIterator __last,
3134 _OutputIterator __result,
3135 const _Tp& __old_value, const _Tp& __new_value)
3136 {
3137 // concept requirements
3138 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3139 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
3140 typename iterator_traits<_InputIterator>::value_type>)
3141 __glibcxx_function_requires(_EqualOpConcept<
3142 typename iterator_traits<_InputIterator>::value_type, _Tp>)
3143 __glibcxx_requires_valid_range(__first, __last);
3144
3145 return std::__replace_copy_if(__first, __last, __result,
3146 __gnu_cxx::__ops::__iter_equals_val(__old_value),
3147 __new_value);
3148 }
3149
3150 /**
3151 * @brief Copy a sequence, replacing each value for which a predicate
3152 * returns true with another value.
3153 * @ingroup mutating_algorithms
3154 * @param __first An input iterator.
3155 * @param __last An input iterator.
3156 * @param __result An output iterator.
3157 * @param __pred A predicate.
3158 * @param __new_value The replacement value.
3159 * @return The end of the output sequence, @p __result+(__last-__first).
3160 *
3161 * Copies each element in the range @p [__first,__last) to the range
3162 * @p [__result,__result+(__last-__first)) replacing elements for which
3163 * @p __pred returns true with @p __new_value.
3164 */
3165 template<typename _InputIterator, typename _OutputIterator,
3166 typename _Predicate, typename _Tp>
3167 inline _OutputIterator
3168 replace_copy_if(_InputIterator __first, _InputIterator __last,
3169 _OutputIterator __result,
3170 _Predicate __pred, const _Tp& __new_value)
3171 {
3172 // concept requirements
3173 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3174 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
3175 typename iterator_traits<_InputIterator>::value_type>)
3176 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
3177 typename iterator_traits<_InputIterator>::value_type>)
3178 __glibcxx_requires_valid_range(__first, __last);
3179
3180 return std::__replace_copy_if(__first, __last, __result,
3181 __gnu_cxx::__ops::__pred_iter(__pred),
3182 __new_value);
3183 }
3184
3185 template<typename _InputIterator, typename _Predicate>
3186 typename iterator_traits<_InputIterator>::difference_type
3187 __count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
3188 {
3189 typename iterator_traits<_InputIterator>::difference_type __n = 0;
3190 for (; __first != __last; ++__first)
3191 if (__pred(__first))
3192 ++__n;
3193 return __n;
3194 }
3195
3196 #if __cplusplus >= 201103L
3197 /**
3198 * @brief Determines whether the elements of a sequence are sorted.
3199 * @ingroup sorting_algorithms
3200 * @param __first An iterator.
3201 * @param __last Another iterator.
3202 * @return True if the elements are sorted, false otherwise.
3203 */
3204 template<typename _ForwardIterator>
3205 inline bool
3206 is_sorted(_ForwardIterator __first, _ForwardIterator __last)
3207 { return std::is_sorted_until(__first, __last) == __last; }
3208
3209 /**
3210 * @brief Determines whether the elements of a sequence are sorted
3211 * according to a comparison functor.
3212 * @ingroup sorting_algorithms
3213 * @param __first An iterator.
3214 * @param __last Another iterator.
3215 * @param __comp A comparison functor.
3216 * @return True if the elements are sorted, false otherwise.
3217 */
3218 template<typename _ForwardIterator, typename _Compare>
3219 inline bool
3220 is_sorted(_ForwardIterator __first, _ForwardIterator __last,
3221 _Compare __comp)
3222 { return std::is_sorted_until(__first, __last, __comp) == __last; }
3223
3224 template<typename _ForwardIterator, typename _Compare>
3225 _ForwardIterator
3226 __is_sorted_until(_ForwardIterator __first, _ForwardIterator __last,
3227 _Compare __comp)
3228 {
3229 if (__first == __last)
3230 return __last;
3231
3232 _ForwardIterator __next = __first;
3233 for (++__next; __next != __last; __first = __next, (void)++__next)
3234 if (__comp(__next, __first))
3235 return __next;
3236 return __next;
3237 }
3238
3239 /**
3240 * @brief Determines the end of a sorted sequence.
3241 * @ingroup sorting_algorithms
3242 * @param __first An iterator.
3243 * @param __last Another iterator.
3244 * @return An iterator pointing to the last iterator i in [__first, __last)
3245 * for which the range [__first, i) is sorted.
3246 */
3247 template<typename _ForwardIterator>
3248 inline _ForwardIterator
3249 is_sorted_until(_ForwardIterator __first, _ForwardIterator __last)
3250 {
3251 // concept requirements
3252 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3253 __glibcxx_function_requires(_LessThanComparableConcept<
3254 typename iterator_traits<_ForwardIterator>::value_type>)
3255 __glibcxx_requires_valid_range(__first, __last);
3256 __glibcxx_requires_irreflexive(__first, __last);
3257
3258 return std::__is_sorted_until(__first, __last,
3259 __gnu_cxx::__ops::__iter_less_iter());
3260 }
3261
3262 /**
3263 * @brief Determines the end of a sorted sequence using comparison functor.
3264 * @ingroup sorting_algorithms
3265 * @param __first An iterator.
3266 * @param __last Another iterator.
3267 * @param __comp A comparison functor.
3268 * @return An iterator pointing to the last iterator i in [__first, __last)
3269 * for which the range [__first, i) is sorted.
3270 */
3271 template<typename _ForwardIterator, typename _Compare>
3272 inline _ForwardIterator
3273 is_sorted_until(_ForwardIterator __first, _ForwardIterator __last,
3274 _Compare __comp)
3275 {
3276 // concept requirements
3277 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3278 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
3279 typename iterator_traits<_ForwardIterator>::value_type,
3280 typename iterator_traits<_ForwardIterator>::value_type>)
3281 __glibcxx_requires_valid_range(__first, __last);
3282 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
3283
3284 return std::__is_sorted_until(__first, __last,
3285 __gnu_cxx::__ops::__iter_comp_iter(__comp));
3286 }
3287
3288 /**
3289 * @brief Determines min and max at once as an ordered pair.
3290 * @ingroup sorting_algorithms
3291 * @param __a A thing of arbitrary type.
3292 * @param __b Another thing of arbitrary type.
3293 * @return A pair(__b, __a) if __b is smaller than __a, pair(__a,
3294 * __b) otherwise.
3295 */
3296 template<typename _Tp>
3297 _GLIBCXX14_CONSTEXPR
3298 inline pair<const _Tp&, const _Tp&>
3299 minmax(const _Tp& __a, const _Tp& __b)
3300 {
3301 // concept requirements
3302 __glibcxx_function_requires(_LessThanComparableConcept<_Tp>)
3303
3304 return __b < __a ? pair<const _Tp&, const _Tp&>(__b, __a)
3305 : pair<const _Tp&, const _Tp&>(__a, __b);
3306 }
3307
3308 /**
3309 * @brief Determines min and max at once as an ordered pair.
3310 * @ingroup sorting_algorithms
3311 * @param __a A thing of arbitrary type.
3312 * @param __b Another thing of arbitrary type.
3313 * @param __comp A @link comparison_functors comparison functor @endlink.
3314 * @return A pair(__b, __a) if __b is smaller than __a, pair(__a,
3315 * __b) otherwise.
3316 */
3317 template<typename _Tp, typename _Compare>
3318 _GLIBCXX14_CONSTEXPR
3319 inline pair<const _Tp&, const _Tp&>
3320 minmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
3321 {
3322 return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a)
3323 : pair<const _Tp&, const _Tp&>(__a, __b);
3324 }
3325
3326 template<typename _ForwardIterator, typename _Compare>
3327 _GLIBCXX14_CONSTEXPR
3328 pair<_ForwardIterator, _ForwardIterator>
3329 __minmax_element(_ForwardIterator __first, _ForwardIterator __last,
3330 _Compare __comp)
3331 {
3332 _ForwardIterator __next = __first;
3333 if (__first == __last
3334 || ++__next == __last)
3335 return std::make_pair(__first, __first);
3336
3337 _ForwardIterator __min{}, __max{};
3338 if (__comp(__next, __first))
3339 {
3340 __min = __next;
3341 __max = __first;
3342 }
3343 else
3344 {
3345 __min = __first;
3346 __max = __next;
3347 }
3348
3349 __first = __next;
3350 ++__first;
3351
3352 while (__first != __last)
3353 {
3354 __next = __first;
3355 if (++__next == __last)
3356 {
3357 if (__comp(__first, __min))
3358 __min = __first;
3359 else if (!__comp(__first, __max))
3360 __max = __first;
3361 break;
3362 }
3363
3364 if (__comp(__next, __first))
3365 {
3366 if (__comp(__next, __min))
3367 __min = __next;
3368 if (!__comp(__first, __max))
3369 __max = __first;
3370 }
3371 else
3372 {
3373 if (__comp(__first, __min))
3374 __min = __first;
3375 if (!__comp(__next, __max))
3376 __max = __next;
3377 }
3378
3379 __first = __next;
3380 ++__first;
3381 }
3382
3383 return std::make_pair(__min, __max);
3384 }
3385
3386 /**
3387 * @brief Return a pair of iterators pointing to the minimum and maximum
3388 * elements in a range.
3389 * @ingroup sorting_algorithms
3390 * @param __first Start of range.
3391 * @param __last End of range.
3392 * @return make_pair(m, M), where m is the first iterator i in
3393 * [__first, __last) such that no other element in the range is
3394 * smaller, and where M is the last iterator i in [__first, __last)
3395 * such that no other element in the range is larger.
3396 */
3397 template<typename _ForwardIterator>
3398 _GLIBCXX14_CONSTEXPR
3399 inline pair<_ForwardIterator, _ForwardIterator>
3400 minmax_element(_ForwardIterator __first, _ForwardIterator __last)
3401 {
3402 // concept requirements
3403 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3404 __glibcxx_function_requires(_LessThanComparableConcept<
3405 typename iterator_traits<_ForwardIterator>::value_type>)
3406 __glibcxx_requires_valid_range(__first, __last);
3407 __glibcxx_requires_irreflexive(__first, __last);
3408
3409 return std::__minmax_element(__first, __last,
3410 __gnu_cxx::__ops::__iter_less_iter());
3411 }
3412
3413 /**
3414 * @brief Return a pair of iterators pointing to the minimum and maximum
3415 * elements in a range.
3416 * @ingroup sorting_algorithms
3417 * @param __first Start of range.
3418 * @param __last End of range.
3419 * @param __comp Comparison functor.
3420 * @return make_pair(m, M), where m is the first iterator i in
3421 * [__first, __last) such that no other element in the range is
3422 * smaller, and where M is the last iterator i in [__first, __last)
3423 * such that no other element in the range is larger.
3424 */
3425 template<typename _ForwardIterator, typename _Compare>
3426 _GLIBCXX14_CONSTEXPR
3427 inline pair<_ForwardIterator, _ForwardIterator>
3428 minmax_element(_ForwardIterator __first, _ForwardIterator __last,
3429 _Compare __comp)
3430 {
3431 // concept requirements
3432 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3433 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
3434 typename iterator_traits<_ForwardIterator>::value_type,
3435 typename iterator_traits<_ForwardIterator>::value_type>)
3436 __glibcxx_requires_valid_range(__first, __last);
3437 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
3438
3439 return std::__minmax_element(__first, __last,
3440 __gnu_cxx::__ops::__iter_comp_iter(__comp));
3441 }
3442
3443 // N2722 + DR 915.
3444 template<typename _Tp>
3445 _GLIBCXX14_CONSTEXPR
3446 inline _Tp
3447 min(initializer_list<_Tp> __l)
3448 { return *std::min_element(__l.begin(), __l.end()); }
3449
3450 template<typename _Tp, typename _Compare>
3451 _GLIBCXX14_CONSTEXPR
3452 inline _Tp
3453 min(initializer_list<_Tp> __l, _Compare __comp)
3454 { return *std::min_element(__l.begin(), __l.end(), __comp); }
3455
3456 template<typename _Tp>
3457 _GLIBCXX14_CONSTEXPR
3458 inline _Tp
3459 max(initializer_list<_Tp> __l)
3460 { return *std::max_element(__l.begin(), __l.end()); }
3461
3462 template<typename _Tp, typename _Compare>
3463 _GLIBCXX14_CONSTEXPR
3464 inline _Tp
3465 max(initializer_list<_Tp> __l, _Compare __comp)
3466 { return *std::max_element(__l.begin(), __l.end(), __comp); }
3467
3468 template<typename _Tp>
3469 _GLIBCXX14_CONSTEXPR
3470 inline pair<_Tp, _Tp>
3471 minmax(initializer_list<_Tp> __l)
3472 {
3473 pair<const _Tp*, const _Tp*> __p =
3474 std::minmax_element(__l.begin(), __l.end());
3475 return std::make_pair(*__p.first, *__p.second);
3476 }
3477
3478 template<typename _Tp, typename _Compare>
3479 _GLIBCXX14_CONSTEXPR
3480 inline pair<_Tp, _Tp>
3481 minmax(initializer_list<_Tp> __l, _Compare __comp)
3482 {
3483 pair<const _Tp*, const _Tp*> __p =
3484 std::minmax_element(__l.begin(), __l.end(), __comp);
3485 return std::make_pair(*__p.first, *__p.second);
3486 }
3487
3488 template<typename _ForwardIterator1, typename _ForwardIterator2,
3489 typename _BinaryPredicate>
3490 bool
3491 __is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
3492 _ForwardIterator2 __first2, _BinaryPredicate __pred)
3493 {
3494 // Efficiently compare identical prefixes: O(N) if sequences
3495 // have the same elements in the same order.
3496 for (; __first1 != __last1; ++__first1, (void)++__first2)
3497 if (!__pred(__first1, __first2))
3498 break;
3499
3500 if (__first1 == __last1)
3501 return true;
3502
3503 // Establish __last2 assuming equal ranges by iterating over the
3504 // rest of the list.
3505 _ForwardIterator2 __last2 = __first2;
3506 std::advance(__last2, std::distance(__first1, __last1));
3507 for (_ForwardIterator1 __scan = __first1; __scan != __last1; ++__scan)
3508 {
3509 if (__scan != std::__find_if(__first1, __scan,
3510 __gnu_cxx::__ops::__iter_comp_iter(__pred, __scan)))
3511 continue; // We've seen this one before.
3512
3513 auto __matches
3514 = std::__count_if(__first2, __last2,
3515 __gnu_cxx::__ops::__iter_comp_iter(__pred, __scan));
3516 if (0 == __matches ||
3517 std::__count_if(__scan, __last1,
3518 __gnu_cxx::__ops::__iter_comp_iter(__pred, __scan))
3519 != __matches)
3520 return false;
3521 }
3522 return true;
3523 }
3524
3525 /**
3526 * @brief Checks whether a permutation of the second sequence is equal
3527 * to the first sequence.
3528 * @ingroup non_mutating_algorithms
3529 * @param __first1 Start of first range.
3530 * @param __last1 End of first range.
3531 * @param __first2 Start of second range.
3532 * @return true if there exists a permutation of the elements in the range
3533 * [__first2, __first2 + (__last1 - __first1)), beginning with
3534 * ForwardIterator2 begin, such that equal(__first1, __last1, begin)
3535 * returns true; otherwise, returns false.
3536 */
3537 template<typename _ForwardIterator1, typename _ForwardIterator2>
3538 inline bool
3539 is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
3540 _ForwardIterator2 __first2)
3541 {
3542 // concept requirements
3543 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
3544 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
3545 __glibcxx_function_requires(_EqualOpConcept<
3546 typename iterator_traits<_ForwardIterator1>::value_type,
3547 typename iterator_traits<_ForwardIterator2>::value_type>)
3548 __glibcxx_requires_valid_range(__first1, __last1);
3549
3550 return std::__is_permutation(__first1, __last1, __first2,
3551 __gnu_cxx::__ops::__iter_equal_to_iter());
3552 }
3553
3554 /**
3555 * @brief Checks whether a permutation of the second sequence is equal
3556 * to the first sequence.
3557 * @ingroup non_mutating_algorithms
3558 * @param __first1 Start of first range.
3559 * @param __last1 End of first range.
3560 * @param __first2 Start of second range.
3561 * @param __pred A binary predicate.
3562 * @return true if there exists a permutation of the elements in
3563 * the range [__first2, __first2 + (__last1 - __first1)),
3564 * beginning with ForwardIterator2 begin, such that
3565 * equal(__first1, __last1, __begin, __pred) returns true;
3566 * otherwise, returns false.
3567 */
3568 template<typename _ForwardIterator1, typename _ForwardIterator2,
3569 typename _BinaryPredicate>
3570 inline bool
3571 is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
3572 _ForwardIterator2 __first2, _BinaryPredicate __pred)
3573 {
3574 // concept requirements
3575 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
3576 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
3577 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
3578 typename iterator_traits<_ForwardIterator1>::value_type,
3579 typename iterator_traits<_ForwardIterator2>::value_type>)
3580 __glibcxx_requires_valid_range(__first1, __last1);
3581
3582 return std::__is_permutation(__first1, __last1, __first2,
3583 __gnu_cxx::__ops::__iter_comp_iter(__pred));
3584 }
3585
3586 #if __cplusplus > 201103L
3587 template<typename _ForwardIterator1, typename _ForwardIterator2,
3588 typename _BinaryPredicate>
3589 bool
3590 __is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
3591 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
3592 _BinaryPredicate __pred)
3593 {
3594 using _Cat1
3595 = typename iterator_traits<_ForwardIterator1>::iterator_category;
3596 using _Cat2
3597 = typename iterator_traits<_ForwardIterator2>::iterator_category;
3598 using _It1_is_RA = is_same<_Cat1, random_access_iterator_tag>;
3599 using _It2_is_RA = is_same<_Cat2, random_access_iterator_tag>;
3600 constexpr bool __ra_iters = _It1_is_RA() && _It2_is_RA();
3601 if (__ra_iters)
3602 {
3603 auto __d1 = std::distance(__first1, __last1);
3604 auto __d2 = std::distance(__first2, __last2);
3605 if (__d1 != __d2)
3606 return false;
3607 }
3608
3609 // Efficiently compare identical prefixes: O(N) if sequences
3610 // have the same elements in the same order.
3611 for (; __first1 != __last1 && __first2 != __last2;
3612 ++__first1, (void)++__first2)
3613 if (!__pred(__first1, __first2))
3614 break;
3615
3616 if (__ra_iters)
3617 {
3618 if (__first1 == __last1)
3619 return true;
3620 }
3621 else
3622 {
3623 auto __d1 = std::distance(__first1, __last1);
3624 auto __d2 = std::distance(__first2, __last2);
3625 if (__d1 == 0 && __d2 == 0)
3626 return true;
3627 if (__d1 != __d2)
3628 return false;
3629 }
3630
3631 for (_ForwardIterator1 __scan = __first1; __scan != __last1; ++__scan)
3632 {
3633 if (__scan != std::__find_if(__first1, __scan,
3634 __gnu_cxx::__ops::__iter_comp_iter(__pred, __scan)))
3635 continue; // We've seen this one before.
3636
3637 auto __matches = std::__count_if(__first2, __last2,
3638 __gnu_cxx::__ops::__iter_comp_iter(__pred, __scan));
3639 if (0 == __matches
3640 || std::__count_if(__scan, __last1,
3641 __gnu_cxx::__ops::__iter_comp_iter(__pred, __scan))
3642 != __matches)
3643 return false;
3644 }
3645 return true;
3646 }
3647
3648 /**
3649 * @brief Checks whether a permutaion of the second sequence is equal
3650 * to the first sequence.
3651 * @ingroup non_mutating_algorithms
3652 * @param __first1 Start of first range.
3653 * @param __last1 End of first range.
3654 * @param __first2 Start of second range.
3655 * @param __last2 End of first range.
3656 * @return true if there exists a permutation of the elements in the range
3657 * [__first2, __last2), beginning with ForwardIterator2 begin,
3658 * such that equal(__first1, __last1, begin) returns true;
3659 * otherwise, returns false.
3660 */
3661 template<typename _ForwardIterator1, typename _ForwardIterator2>
3662 inline bool
3663 is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
3664 _ForwardIterator2 __first2, _ForwardIterator2 __last2)
3665 {
3666 __glibcxx_requires_valid_range(__first1, __last1);
3667 __glibcxx_requires_valid_range(__first2, __last2);
3668
3669 return
3670 std::__is_permutation(__first1, __last1, __first2, __last2,
3671 __gnu_cxx::__ops::__iter_equal_to_iter());
3672 }
3673
3674 /**
3675 * @brief Checks whether a permutation of the second sequence is equal
3676 * to the first sequence.
3677 * @ingroup non_mutating_algorithms
3678 * @param __first1 Start of first range.
3679 * @param __last1 End of first range.
3680 * @param __first2 Start of second range.
3681 * @param __last2 End of first range.
3682 * @param __pred A binary predicate.
3683 * @return true if there exists a permutation of the elements in the range
3684 * [__first2, __last2), beginning with ForwardIterator2 begin,
3685 * such that equal(__first1, __last1, __begin, __pred) returns true;
3686 * otherwise, returns false.
3687 */
3688 template<typename _ForwardIterator1, typename _ForwardIterator2,
3689 typename _BinaryPredicate>
3690 inline bool
3691 is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
3692 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
3693 _BinaryPredicate __pred)
3694 {
3695 __glibcxx_requires_valid_range(__first1, __last1);
3696 __glibcxx_requires_valid_range(__first2, __last2);
3697
3698 return std::__is_permutation(__first1, __last1, __first2, __last2,
3699 __gnu_cxx::__ops::__iter_comp_iter(__pred));
3700 }
3701 #endif
3702
3703 #ifdef _GLIBCXX_USE_C99_STDINT_TR1
3704 /**
3705 * @brief Shuffle the elements of a sequence using a uniform random
3706 * number generator.
3707 * @ingroup mutating_algorithms
3708 * @param __first A forward iterator.
3709 * @param __last A forward iterator.
3710 * @param __g A UniformRandomNumberGenerator (26.5.1.3).
3711 * @return Nothing.
3712 *
3713 * Reorders the elements in the range @p [__first,__last) using @p __g to
3714 * provide random numbers.
3715 */
3716 template<typename _RandomAccessIterator,
3717 typename _UniformRandomNumberGenerator>
3718 void
3719 shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
3720 _UniformRandomNumberGenerator&& __g)
3721 {
3722 // concept requirements
3723 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
3724 _RandomAccessIterator>)
3725 __glibcxx_requires_valid_range(__first, __last);
3726
3727 if (__first == __last)
3728 return;
3729
3730 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
3731 _DistanceType;
3732
3733 typedef typename std::make_unsigned<_DistanceType>::type __ud_type;
3734 typedef typename std::uniform_int_distribution<__ud_type> __distr_type;
3735 typedef typename __distr_type::param_type __p_type;
3736 __distr_type __d;
3737
3738 for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
3739 std::iter_swap(__i, __first + __d(__g, __p_type(0, __i - __first)));
3740 }
3741 #endif
3742
3743 #endif // C++11
3744
3745 _GLIBCXX_END_NAMESPACE_VERSION
3746
3747 _GLIBCXX_BEGIN_NAMESPACE_ALGO
3748
3749 /**
3750 * @brief Apply a function to every element of a sequence.
3751 * @ingroup non_mutating_algorithms
3752 * @param __first An input iterator.
3753 * @param __last An input iterator.
3754 * @param __f A unary function object.
3755 * @return @p __f (std::move(@p __f) in C++0x).
3756 *
3757 * Applies the function object @p __f to each element in the range
3758 * @p [first,last). @p __f must not modify the order of the sequence.
3759 * If @p __f has a return value it is ignored.
3760 */
3761 template<typename _InputIterator, typename _Function>
3762 _Function
3763 for_each(_InputIterator __first, _InputIterator __last, _Function __f)
3764 {
3765 // concept requirements
3766 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3767 __glibcxx_requires_valid_range(__first, __last);
3768 for (; __first != __last; ++__first)
3769 __f(*__first);
3770 return _GLIBCXX_MOVE(__f);
3771 }
3772
3773 /**
3774 * @brief Find the first occurrence of a value in a sequence.
3775 * @ingroup non_mutating_algorithms
3776 * @param __first An input iterator.
3777 * @param __last An input iterator.
3778 * @param __val The value to find.
3779 * @return The first iterator @c i in the range @p [__first,__last)
3780 * such that @c *i == @p __val, or @p __last if no such iterator exists.
3781 */
3782 template<typename _InputIterator, typename _Tp>
3783 inline _InputIterator
3784 find(_InputIterator __first, _InputIterator __last,
3785 const _Tp& __val)
3786 {
3787 // concept requirements
3788 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3789 __glibcxx_function_requires(_EqualOpConcept<
3790 typename iterator_traits<_InputIterator>::value_type, _Tp>)
3791 __glibcxx_requires_valid_range(__first, __last);
3792 return std::__find_if(__first, __last,
3793 __gnu_cxx::__ops::__iter_equals_val(__val));
3794 }
3795
3796 /**
3797 * @brief Find the first element in a sequence for which a
3798 * predicate is true.
3799 * @ingroup non_mutating_algorithms
3800 * @param __first An input iterator.
3801 * @param __last An input iterator.
3802 * @param __pred A predicate.
3803 * @return The first iterator @c i in the range @p [__first,__last)
3804 * such that @p __pred(*i) is true, or @p __last if no such iterator exists.
3805 */
3806 template<typename _InputIterator, typename _Predicate>
3807 inline _InputIterator
3808 find_if(_InputIterator __first, _InputIterator __last,
3809 _Predicate __pred)
3810 {
3811 // concept requirements
3812 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3813 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
3814 typename iterator_traits<_InputIterator>::value_type>)
3815 __glibcxx_requires_valid_range(__first, __last);
3816
3817 return std::__find_if(__first, __last,
3818 __gnu_cxx::__ops::__pred_iter(__pred));
3819 }
3820
3821 /**
3822 * @brief Find element from a set in a sequence.
3823 * @ingroup non_mutating_algorithms
3824 * @param __first1 Start of range to search.
3825 * @param __last1 End of range to search.
3826 * @param __first2 Start of match candidates.
3827 * @param __last2 End of match candidates.
3828 * @return The first iterator @c i in the range
3829 * @p [__first1,__last1) such that @c *i == @p *(i2) such that i2 is an
3830 * iterator in [__first2,__last2), or @p __last1 if no such iterator exists.
3831 *
3832 * Searches the range @p [__first1,__last1) for an element that is
3833 * equal to some element in the range [__first2,__last2). If
3834 * found, returns an iterator in the range [__first1,__last1),
3835 * otherwise returns @p __last1.
3836 */
3837 template<typename _InputIterator, typename _ForwardIterator>
3838 _InputIterator
3839 find_first_of(_InputIterator __first1, _InputIterator __last1,
3840 _ForwardIterator __first2, _ForwardIterator __last2)
3841 {
3842 // concept requirements
3843 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3844 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3845 __glibcxx_function_requires(_EqualOpConcept<
3846 typename iterator_traits<_InputIterator>::value_type,
3847 typename iterator_traits<_ForwardIterator>::value_type>)
3848 __glibcxx_requires_valid_range(__first1, __last1);
3849 __glibcxx_requires_valid_range(__first2, __last2);
3850
3851 for (; __first1 != __last1; ++__first1)
3852 for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter)
3853 if (*__first1 == *__iter)
3854 return __first1;
3855 return __last1;
3856 }
3857
3858 /**
3859 * @brief Find element from a set in a sequence using a predicate.
3860 * @ingroup non_mutating_algorithms
3861 * @param __first1 Start of range to search.
3862 * @param __last1 End of range to search.
3863 * @param __first2 Start of match candidates.
3864 * @param __last2 End of match candidates.
3865 * @param __comp Predicate to use.
3866 * @return The first iterator @c i in the range
3867 * @p [__first1,__last1) such that @c comp(*i, @p *(i2)) is true
3868 * and i2 is an iterator in [__first2,__last2), or @p __last1 if no
3869 * such iterator exists.
3870 *
3871
3872 * Searches the range @p [__first1,__last1) for an element that is
3873 * equal to some element in the range [__first2,__last2). If
3874 * found, returns an iterator in the range [__first1,__last1),
3875 * otherwise returns @p __last1.
3876 */
3877 template<typename _InputIterator, typename _ForwardIterator,
3878 typename _BinaryPredicate>
3879 _InputIterator
3880 find_first_of(_InputIterator __first1, _InputIterator __last1,
3881 _ForwardIterator __first2, _ForwardIterator __last2,
3882 _BinaryPredicate __comp)
3883 {
3884 // concept requirements
3885 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3886 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3887 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
3888 typename iterator_traits<_InputIterator>::value_type,
3889 typename iterator_traits<_ForwardIterator>::value_type>)
3890 __glibcxx_requires_valid_range(__first1, __last1);
3891 __glibcxx_requires_valid_range(__first2, __last2);
3892
3893 for (; __first1 != __last1; ++__first1)
3894 for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter)
3895 if (__comp(*__first1, *__iter))
3896 return __first1;
3897 return __last1;
3898 }
3899
3900 /**
3901 * @brief Find two adjacent values in a sequence that are equal.
3902 * @ingroup non_mutating_algorithms
3903 * @param __first A forward iterator.
3904 * @param __last A forward iterator.
3905 * @return The first iterator @c i such that @c i and @c i+1 are both
3906 * valid iterators in @p [__first,__last) and such that @c *i == @c *(i+1),
3907 * or @p __last if no such iterator exists.
3908 */
3909 template<typename _ForwardIterator>
3910 inline _ForwardIterator
3911 adjacent_find(_ForwardIterator __first, _ForwardIterator __last)
3912 {
3913 // concept requirements
3914 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3915 __glibcxx_function_requires(_EqualityComparableConcept<
3916 typename iterator_traits<_ForwardIterator>::value_type>)
3917 __glibcxx_requires_valid_range(__first, __last);
3918
3919 return std::__adjacent_find(__first, __last,
3920 __gnu_cxx::__ops::__iter_equal_to_iter());
3921 }
3922
3923 /**
3924 * @brief Find two adjacent values in a sequence using a predicate.
3925 * @ingroup non_mutating_algorithms
3926 * @param __first A forward iterator.
3927 * @param __last A forward iterator.
3928 * @param __binary_pred A binary predicate.
3929 * @return The first iterator @c i such that @c i and @c i+1 are both
3930 * valid iterators in @p [__first,__last) and such that
3931 * @p __binary_pred(*i,*(i+1)) is true, or @p __last if no such iterator
3932 * exists.
3933 */
3934 template<typename _ForwardIterator, typename _BinaryPredicate>
3935 inline _ForwardIterator
3936 adjacent_find(_ForwardIterator __first, _ForwardIterator __last,
3937 _BinaryPredicate __binary_pred)
3938 {
3939 // concept requirements
3940 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3941 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
3942 typename iterator_traits<_ForwardIterator>::value_type,
3943 typename iterator_traits<_ForwardIterator>::value_type>)
3944 __glibcxx_requires_valid_range(__first, __last);
3945
3946 return std::__adjacent_find(__first, __last,
3947 __gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
3948 }
3949
3950 /**
3951 * @brief Count the number of copies of a value in a sequence.
3952 * @ingroup non_mutating_algorithms
3953 * @param __first An input iterator.
3954 * @param __last An input iterator.
3955 * @param __value The value to be counted.
3956 * @return The number of iterators @c i in the range @p [__first,__last)
3957 * for which @c *i == @p __value
3958 */
3959 template<typename _InputIterator, typename _Tp>
3960 inline typename iterator_traits<_InputIterator>::difference_type
3961 count(_InputIterator __first, _InputIterator __last, const _Tp& __value)
3962 {
3963 // concept requirements
3964 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3965 __glibcxx_function_requires(_EqualOpConcept<
3966 typename iterator_traits<_InputIterator>::value_type, _Tp>)
3967 __glibcxx_requires_valid_range(__first, __last);
3968
3969 return std::__count_if(__first, __last,
3970 __gnu_cxx::__ops::__iter_equals_val(__value));
3971 }
3972
3973 /**
3974 * @brief Count the elements of a sequence for which a predicate is true.
3975 * @ingroup non_mutating_algorithms
3976 * @param __first An input iterator.
3977 * @param __last An input iterator.
3978 * @param __pred A predicate.
3979 * @return The number of iterators @c i in the range @p [__first,__last)
3980 * for which @p __pred(*i) is true.
3981 */
3982 template<typename _InputIterator, typename _Predicate>
3983 inline typename iterator_traits<_InputIterator>::difference_type
3984 count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
3985 {
3986 // concept requirements
3987 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3988 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
3989 typename iterator_traits<_InputIterator>::value_type>)
3990 __glibcxx_requires_valid_range(__first, __last);
3991
3992 return std::__count_if(__first, __last,
3993 __gnu_cxx::__ops::__pred_iter(__pred));
3994 }
3995
3996 /**
3997 * @brief Search a sequence for a matching sub-sequence.
3998 * @ingroup non_mutating_algorithms
3999 * @param __first1 A forward iterator.
4000 * @param __last1 A forward iterator.
4001 * @param __first2 A forward iterator.
4002 * @param __last2 A forward iterator.
4003 * @return The first iterator @c i in the range @p
4004 * [__first1,__last1-(__last2-__first2)) such that @c *(i+N) == @p
4005 * *(__first2+N) for each @c N in the range @p
4006 * [0,__last2-__first2), or @p __last1 if no such iterator exists.
4007 *
4008 * Searches the range @p [__first1,__last1) for a sub-sequence that
4009 * compares equal value-by-value with the sequence given by @p
4010 * [__first2,__last2) and returns an iterator to the first element
4011 * of the sub-sequence, or @p __last1 if the sub-sequence is not
4012 * found.
4013 *
4014 * Because the sub-sequence must lie completely within the range @p
4015 * [__first1,__last1) it must start at a position less than @p
4016 * __last1-(__last2-__first2) where @p __last2-__first2 is the
4017 * length of the sub-sequence.
4018 *
4019 * This means that the returned iterator @c i will be in the range
4020 * @p [__first1,__last1-(__last2-__first2))
4021 */
4022 template<typename _ForwardIterator1, typename _ForwardIterator2>
4023 inline _ForwardIterator1
4024 search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
4025 _ForwardIterator2 __first2, _ForwardIterator2 __last2)
4026 {
4027 // concept requirements
4028 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
4029 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
4030 __glibcxx_function_requires(_EqualOpConcept<
4031 typename iterator_traits<_ForwardIterator1>::value_type,
4032 typename iterator_traits<_ForwardIterator2>::value_type>)
4033 __glibcxx_requires_valid_range(__first1, __last1);
4034 __glibcxx_requires_valid_range(__first2, __last2);
4035
4036 return std::__search(__first1, __last1, __first2, __last2,
4037 __gnu_cxx::__ops::__iter_equal_to_iter());
4038 }
4039
4040 /**
4041 * @brief Search a sequence for a matching sub-sequence using a predicate.
4042 * @ingroup non_mutating_algorithms
4043 * @param __first1 A forward iterator.
4044 * @param __last1 A forward iterator.
4045 * @param __first2 A forward iterator.
4046 * @param __last2 A forward iterator.
4047 * @param __predicate A binary predicate.
4048 * @return The first iterator @c i in the range
4049 * @p [__first1,__last1-(__last2-__first2)) such that
4050 * @p __predicate(*(i+N),*(__first2+N)) is true for each @c N in the range
4051 * @p [0,__last2-__first2), or @p __last1 if no such iterator exists.
4052 *
4053 * Searches the range @p [__first1,__last1) for a sub-sequence that
4054 * compares equal value-by-value with the sequence given by @p
4055 * [__first2,__last2), using @p __predicate to determine equality,
4056 * and returns an iterator to the first element of the
4057 * sub-sequence, or @p __last1 if no such iterator exists.
4058 *
4059 * @see search(_ForwardIter1, _ForwardIter1, _ForwardIter2, _ForwardIter2)
4060 */
4061 template<typename _ForwardIterator1, typename _ForwardIterator2,
4062 typename _BinaryPredicate>
4063 inline _ForwardIterator1
4064 search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
4065 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
4066 _BinaryPredicate __predicate)
4067 {
4068 // concept requirements
4069 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
4070 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
4071 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
4072 typename iterator_traits<_ForwardIterator1>::value_type,
4073 typename iterator_traits<_ForwardIterator2>::value_type>)
4074 __glibcxx_requires_valid_range(__first1, __last1);
4075 __glibcxx_requires_valid_range(__first2, __last2);
4076
4077 return std::__search(__first1, __last1, __first2, __last2,
4078 __gnu_cxx::__ops::__iter_comp_iter(__predicate));
4079 }
4080
4081 /**
4082 * @brief Search a sequence for a number of consecutive values.
4083 * @ingroup non_mutating_algorithms
4084 * @param __first A forward iterator.
4085 * @param __last A forward iterator.
4086 * @param __count The number of consecutive values.
4087 * @param __val The value to find.
4088 * @return The first iterator @c i in the range @p
4089 * [__first,__last-__count) such that @c *(i+N) == @p __val for
4090 * each @c N in the range @p [0,__count), or @p __last if no such
4091 * iterator exists.
4092 *
4093 * Searches the range @p [__first,__last) for @p count consecutive elements
4094 * equal to @p __val.
4095 */
4096 template<typename _ForwardIterator, typename _Integer, typename _Tp>
4097 inline _ForwardIterator
4098 search_n(_ForwardIterator __first, _ForwardIterator __last,
4099 _Integer __count, const _Tp& __val)
4100 {
4101 // concept requirements
4102 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
4103 __glibcxx_function_requires(_EqualOpConcept<
4104 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
4105 __glibcxx_requires_valid_range(__first, __last);
4106
4107 return std::__search_n(__first, __last, __count,
4108 __gnu_cxx::__ops::__iter_equals_val(__val));
4109 }
4110
4111
4112 /**
4113 * @brief Search a sequence for a number of consecutive values using a
4114 * predicate.
4115 * @ingroup non_mutating_algorithms
4116 * @param __first A forward iterator.
4117 * @param __last A forward iterator.
4118 * @param __count The number of consecutive values.
4119 * @param __val The value to find.
4120 * @param __binary_pred A binary predicate.
4121 * @return The first iterator @c i in the range @p
4122 * [__first,__last-__count) such that @p
4123 * __binary_pred(*(i+N),__val) is true for each @c N in the range
4124 * @p [0,__count), or @p __last if no such iterator exists.
4125 *
4126 * Searches the range @p [__first,__last) for @p __count
4127 * consecutive elements for which the predicate returns true.
4128 */
4129 template<typename _ForwardIterator, typename _Integer, typename _Tp,
4130 typename _BinaryPredicate>
4131 inline _ForwardIterator
4132 search_n(_ForwardIterator __first, _ForwardIterator __last,
4133 _Integer __count, const _Tp& __val,
4134 _BinaryPredicate __binary_pred)
4135 {
4136 // concept requirements
4137 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
4138 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
4139 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
4140 __glibcxx_requires_valid_range(__first, __last);
4141
4142 return std::__search_n(__first, __last, __count,
4143 __gnu_cxx::__ops::__iter_comp_val(__binary_pred, __val));
4144 }
4145
4146
4147 /**
4148 * @brief Perform an operation on a sequence.
4149 * @ingroup mutating_algorithms
4150 * @param __first An input iterator.
4151 * @param __last An input iterator.
4152 * @param __result An output iterator.
4153 * @param __unary_op A unary operator.
4154 * @return An output iterator equal to @p __result+(__last-__first).
4155 *
4156 * Applies the operator to each element in the input range and assigns
4157 * the results to successive elements of the output sequence.
4158 * Evaluates @p *(__result+N)=unary_op(*(__first+N)) for each @c N in the
4159 * range @p [0,__last-__first).
4160 *
4161 * @p unary_op must not alter its argument.
4162 */
4163 template<typename _InputIterator, typename _OutputIterator,
4164 typename _UnaryOperation>
4165 _OutputIterator
4166 transform(_InputIterator __first, _InputIterator __last,
4167 _OutputIterator __result, _UnaryOperation __unary_op)
4168 {
4169 // concept requirements
4170 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
4171 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4172 // "the type returned by a _UnaryOperation"
4173 __typeof__(__unary_op(*__first))>)
4174 __glibcxx_requires_valid_range(__first, __last);
4175
4176 for (; __first != __last; ++__first, (void)++__result)
4177 *__result = __unary_op(*__first);
4178 return __result;
4179 }
4180
4181 /**
4182 * @brief Perform an operation on corresponding elements of two sequences.
4183 * @ingroup mutating_algorithms
4184 * @param __first1 An input iterator.
4185 * @param __last1 An input iterator.
4186 * @param __first2 An input iterator.
4187 * @param __result An output iterator.
4188 * @param __binary_op A binary operator.
4189 * @return An output iterator equal to @p result+(last-first).
4190 *
4191 * Applies the operator to the corresponding elements in the two
4192 * input ranges and assigns the results to successive elements of the
4193 * output sequence.
4194 * Evaluates @p
4195 * *(__result+N)=__binary_op(*(__first1+N),*(__first2+N)) for each
4196 * @c N in the range @p [0,__last1-__first1).
4197 *
4198 * @p binary_op must not alter either of its arguments.
4199 */
4200 template<typename _InputIterator1, typename _InputIterator2,
4201 typename _OutputIterator, typename _BinaryOperation>
4202 _OutputIterator
4203 transform(_InputIterator1 __first1, _InputIterator1 __last1,
4204 _InputIterator2 __first2, _OutputIterator __result,
4205 _BinaryOperation __binary_op)
4206 {
4207 // concept requirements
4208 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
4209 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
4210 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4211 // "the type returned by a _BinaryOperation"
4212 __typeof__(__binary_op(*__first1,*__first2))>)
4213 __glibcxx_requires_valid_range(__first1, __last1);
4214
4215 for (; __first1 != __last1; ++__first1, (void)++__first2, ++__result)
4216 *__result = __binary_op(*__first1, *__first2);
4217 return __result;
4218 }
4219
4220 /**
4221 * @brief Replace each occurrence of one value in a sequence with another
4222 * value.
4223 * @ingroup mutating_algorithms
4224 * @param __first A forward iterator.
4225 * @param __last A forward iterator.
4226 * @param __old_value The value to be replaced.
4227 * @param __new_value The replacement value.
4228 * @return replace() returns no value.
4229 *
4230 * For each iterator @c i in the range @p [__first,__last) if @c *i ==
4231 * @p __old_value then the assignment @c *i = @p __new_value is performed.
4232 */
4233 template<typename _ForwardIterator, typename _Tp>
4234 void
4235 replace(_ForwardIterator __first, _ForwardIterator __last,
4236 const _Tp& __old_value, const _Tp& __new_value)
4237 {
4238 // concept requirements
4239 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
4240 _ForwardIterator>)
4241 __glibcxx_function_requires(_EqualOpConcept<
4242 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
4243 __glibcxx_function_requires(_ConvertibleConcept<_Tp,
4244 typename iterator_traits<_ForwardIterator>::value_type>)
4245 __glibcxx_requires_valid_range(__first, __last);
4246
4247 for (; __first != __last; ++__first)
4248 if (*__first == __old_value)
4249 *__first = __new_value;
4250 }
4251
4252 /**
4253 * @brief Replace each value in a sequence for which a predicate returns
4254 * true with another value.
4255 * @ingroup mutating_algorithms
4256 * @param __first A forward iterator.
4257 * @param __last A forward iterator.
4258 * @param __pred A predicate.
4259 * @param __new_value The replacement value.
4260 * @return replace_if() returns no value.
4261 *
4262 * For each iterator @c i in the range @p [__first,__last) if @p __pred(*i)
4263 * is true then the assignment @c *i = @p __new_value is performed.
4264 */
4265 template<typename _ForwardIterator, typename _Predicate, typename _Tp>
4266 void
4267 replace_if(_ForwardIterator __first, _ForwardIterator __last,
4268 _Predicate __pred, const _Tp& __new_value)
4269 {
4270 // concept requirements
4271 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
4272 _ForwardIterator>)
4273 __glibcxx_function_requires(_ConvertibleConcept<_Tp,
4274 typename iterator_traits<_ForwardIterator>::value_type>)
4275 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
4276 typename iterator_traits<_ForwardIterator>::value_type>)
4277 __glibcxx_requires_valid_range(__first, __last);
4278
4279 for (; __first != __last; ++__first)
4280 if (__pred(*__first))
4281 *__first = __new_value;
4282 }
4283
4284 /**
4285 * @brief Assign the result of a function object to each value in a
4286 * sequence.
4287 * @ingroup mutating_algorithms
4288 * @param __first A forward iterator.
4289 * @param __last A forward iterator.
4290 * @param __gen A function object taking no arguments and returning
4291 * std::iterator_traits<_ForwardIterator>::value_type
4292 * @return generate() returns no value.
4293 *
4294 * Performs the assignment @c *i = @p __gen() for each @c i in the range
4295 * @p [__first,__last).
4296 */
4297 template<typename _ForwardIterator, typename _Generator>
4298 void
4299 generate(_ForwardIterator __first, _ForwardIterator __last,
4300 _Generator __gen)
4301 {
4302 // concept requirements
4303 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
4304 __glibcxx_function_requires(_GeneratorConcept<_Generator,
4305 typename iterator_traits<_ForwardIterator>::value_type>)
4306 __glibcxx_requires_valid_range(__first, __last);
4307
4308 for (; __first != __last; ++__first)
4309 *__first = __gen();
4310 }
4311
4312 /**
4313 * @brief Assign the result of a function object to each value in a
4314 * sequence.
4315 * @ingroup mutating_algorithms
4316 * @param __first A forward iterator.
4317 * @param __n The length of the sequence.
4318 * @param __gen A function object taking no arguments and returning
4319 * std::iterator_traits<_ForwardIterator>::value_type
4320 * @return The end of the sequence, @p __first+__n
4321 *
4322 * Performs the assignment @c *i = @p __gen() for each @c i in the range
4323 * @p [__first,__first+__n).
4324 *
4325 * _GLIBCXX_RESOLVE_LIB_DEFECTS
4326 * DR 865. More algorithms that throw away information
4327 */
4328 template<typename _OutputIterator, typename _Size, typename _Generator>
4329 _OutputIterator
4330 generate_n(_OutputIterator __first, _Size __n, _Generator __gen)
4331 {
4332 // concept requirements
4333 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4334 // "the type returned by a _Generator"
4335 __typeof__(__gen())>)
4336
4337 for (__decltype(__n + 0) __niter = __n;
4338 __niter > 0; --__niter, ++__first)
4339 *__first = __gen();
4340 return __first;
4341 }
4342
4343 /**
4344 * @brief Copy a sequence, removing consecutive duplicate values.
4345 * @ingroup mutating_algorithms
4346 * @param __first An input iterator.
4347 * @param __last An input iterator.
4348 * @param __result An output iterator.
4349 * @return An iterator designating the end of the resulting sequence.
4350 *
4351 * Copies each element in the range @p [__first,__last) to the range
4352 * beginning at @p __result, except that only the first element is copied
4353 * from groups of consecutive elements that compare equal.
4354 * unique_copy() is stable, so the relative order of elements that are
4355 * copied is unchanged.
4356 *
4357 * _GLIBCXX_RESOLVE_LIB_DEFECTS
4358 * DR 241. Does unique_copy() require CopyConstructible and Assignable?
4359 *
4360 * _GLIBCXX_RESOLVE_LIB_DEFECTS
4361 * DR 538. 241 again: Does unique_copy() require CopyConstructible and
4362 * Assignable?
4363 */
4364 template<typename _InputIterator, typename _OutputIterator>
4365 inline _OutputIterator
4366 unique_copy(_InputIterator __first, _InputIterator __last,
4367 _OutputIterator __result)
4368 {
4369 // concept requirements
4370 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
4371 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4372 typename iterator_traits<_InputIterator>::value_type>)
4373 __glibcxx_function_requires(_EqualityComparableConcept<
4374 typename iterator_traits<_InputIterator>::value_type>)
4375 __glibcxx_requires_valid_range(__first, __last);
4376
4377 if (__first == __last)
4378 return __result;
4379 return std::__unique_copy(__first, __last, __result,
4380 __gnu_cxx::__ops::__iter_equal_to_iter(),
4381 std::__iterator_category(__first),
4382 std::__iterator_category(__result));
4383 }
4384
4385 /**
4386 * @brief Copy a sequence, removing consecutive values using a predicate.
4387 * @ingroup mutating_algorithms
4388 * @param __first An input iterator.
4389 * @param __last An input iterator.
4390 * @param __result An output iterator.
4391 * @param __binary_pred A binary predicate.
4392 * @return An iterator designating the end of the resulting sequence.
4393 *
4394 * Copies each element in the range @p [__first,__last) to the range
4395 * beginning at @p __result, except that only the first element is copied
4396 * from groups of consecutive elements for which @p __binary_pred returns
4397 * true.
4398 * unique_copy() is stable, so the relative order of elements that are
4399 * copied is unchanged.
4400 *
4401 * _GLIBCXX_RESOLVE_LIB_DEFECTS
4402 * DR 241. Does unique_copy() require CopyConstructible and Assignable?
4403 */
4404 template<typename _InputIterator, typename _OutputIterator,
4405 typename _BinaryPredicate>
4406 inline _OutputIterator
4407 unique_copy(_InputIterator __first, _InputIterator __last,
4408 _OutputIterator __result,
4409 _BinaryPredicate __binary_pred)
4410 {
4411 // concept requirements -- predicates checked later
4412 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
4413 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4414 typename iterator_traits<_InputIterator>::value_type>)
4415 __glibcxx_requires_valid_range(__first, __last);
4416
4417 if (__first == __last)
4418 return __result;
4419 return std::__unique_copy(__first, __last, __result,
4420 __gnu_cxx::__ops::__iter_comp_iter(__binary_pred),
4421 std::__iterator_category(__first),
4422 std::__iterator_category(__result));
4423 }
4424
4425 #if _GLIBCXX_HOSTED
4426 /**
4427 * @brief Randomly shuffle the elements of a sequence.
4428 * @ingroup mutating_algorithms
4429 * @param __first A forward iterator.
4430 * @param __last A forward iterator.
4431 * @return Nothing.
4432 *
4433 * Reorder the elements in the range @p [__first,__last) using a random
4434 * distribution, so that every possible ordering of the sequence is
4435 * equally likely.
4436 */
4437 template<typename _RandomAccessIterator>
4438 inline void
4439 random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last)
4440 {
4441 // concept requirements
4442 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4443 _RandomAccessIterator>)
4444 __glibcxx_requires_valid_range(__first, __last);
4445
4446 if (__first != __last)
4447 for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
4448 {
4449 // XXX rand() % N is not uniformly distributed
4450 _RandomAccessIterator __j = __first
4451 + std::rand() % ((__i - __first) + 1);
4452 if (__i != __j)
4453 std::iter_swap(__i, __j);
4454 }
4455 }
4456 #endif
4457
4458 /**
4459 * @brief Shuffle the elements of a sequence using a random number
4460 * generator.
4461 * @ingroup mutating_algorithms
4462 * @param __first A forward iterator.
4463 * @param __last A forward iterator.
4464 * @param __rand The RNG functor or function.
4465 * @return Nothing.
4466 *
4467 * Reorders the elements in the range @p [__first,__last) using @p __rand to
4468 * provide a random distribution. Calling @p __rand(N) for a positive
4469 * integer @p N should return a randomly chosen integer from the
4470 * range [0,N).
4471 */
4472 template<typename _RandomAccessIterator, typename _RandomNumberGenerator>
4473 void
4474 random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
4475 #if __cplusplus >= 201103L
4476 _RandomNumberGenerator&& __rand)
4477 #else
4478 _RandomNumberGenerator& __rand)
4479 #endif
4480 {
4481 // concept requirements
4482 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4483 _RandomAccessIterator>)
4484 __glibcxx_requires_valid_range(__first, __last);
4485
4486 if (__first == __last)
4487 return;
4488 for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
4489 {
4490 _RandomAccessIterator __j = __first + __rand((__i - __first) + 1);
4491 if (__i != __j)
4492 std::iter_swap(__i, __j);
4493 }
4494 }
4495
4496
4497 /**
4498 * @brief Move elements for which a predicate is true to the beginning
4499 * of a sequence.
4500 * @ingroup mutating_algorithms
4501 * @param __first A forward iterator.
4502 * @param __last A forward iterator.
4503 * @param __pred A predicate functor.
4504 * @return An iterator @p middle such that @p __pred(i) is true for each
4505 * iterator @p i in the range @p [__first,middle) and false for each @p i
4506 * in the range @p [middle,__last).
4507 *
4508 * @p __pred must not modify its operand. @p partition() does not preserve
4509 * the relative ordering of elements in each group, use
4510 * @p stable_partition() if this is needed.
4511 */
4512 template<typename _ForwardIterator, typename _Predicate>
4513 inline _ForwardIterator
4514 partition(_ForwardIterator __first, _ForwardIterator __last,
4515 _Predicate __pred)
4516 {
4517 // concept requirements
4518 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
4519 _ForwardIterator>)
4520 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
4521 typename iterator_traits<_ForwardIterator>::value_type>)
4522 __glibcxx_requires_valid_range(__first, __last);
4523
4524 return std::__partition(__first, __last, __pred,
4525 std::__iterator_category(__first));
4526 }
4527
4528
4529 /**
4530 * @brief Sort the smallest elements of a sequence.
4531 * @ingroup sorting_algorithms
4532 * @param __first An iterator.
4533 * @param __middle Another iterator.
4534 * @param __last Another iterator.
4535 * @return Nothing.
4536 *
4537 * Sorts the smallest @p (__middle-__first) elements in the range
4538 * @p [first,last) and moves them to the range @p [__first,__middle). The
4539 * order of the remaining elements in the range @p [__middle,__last) is
4540 * undefined.
4541 * After the sort if @e i and @e j are iterators in the range
4542 * @p [__first,__middle) such that i precedes j and @e k is an iterator in
4543 * the range @p [__middle,__last) then *j<*i and *k<*i are both false.
4544 */
4545 template<typename _RandomAccessIterator>
4546 inline void
4547 partial_sort(_RandomAccessIterator __first,
4548 _RandomAccessIterator __middle,
4549 _RandomAccessIterator __last)
4550 {
4551 // concept requirements
4552 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4553 _RandomAccessIterator>)
4554 __glibcxx_function_requires(_LessThanComparableConcept<
4555 typename iterator_traits<_RandomAccessIterator>::value_type>)
4556 __glibcxx_requires_valid_range(__first, __middle);
4557 __glibcxx_requires_valid_range(__middle, __last);
4558 __glibcxx_requires_irreflexive(__first, __last);
4559
4560 std::__partial_sort(__first, __middle, __last,
4561 __gnu_cxx::__ops::__iter_less_iter());
4562 }
4563
4564 /**
4565 * @brief Sort the smallest elements of a sequence using a predicate
4566 * for comparison.
4567 * @ingroup sorting_algorithms
4568 * @param __first An iterator.
4569 * @param __middle Another iterator.
4570 * @param __last Another iterator.
4571 * @param __comp A comparison functor.
4572 * @return Nothing.
4573 *
4574 * Sorts the smallest @p (__middle-__first) elements in the range
4575 * @p [__first,__last) and moves them to the range @p [__first,__middle). The
4576 * order of the remaining elements in the range @p [__middle,__last) is
4577 * undefined.
4578 * After the sort if @e i and @e j are iterators in the range
4579 * @p [__first,__middle) such that i precedes j and @e k is an iterator in
4580 * the range @p [__middle,__last) then @p *__comp(j,*i) and @p __comp(*k,*i)
4581 * are both false.
4582 */
4583 template<typename _RandomAccessIterator, typename _Compare>
4584 inline void
4585 partial_sort(_RandomAccessIterator __first,
4586 _RandomAccessIterator __middle,
4587 _RandomAccessIterator __last,
4588 _Compare __comp)
4589 {
4590 // concept requirements
4591 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4592 _RandomAccessIterator>)
4593 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
4594 typename iterator_traits<_RandomAccessIterator>::value_type,
4595 typename iterator_traits<_RandomAccessIterator>::value_type>)
4596 __glibcxx_requires_valid_range(__first, __middle);
4597 __glibcxx_requires_valid_range(__middle, __last);
4598 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
4599
4600 std::__partial_sort(__first, __middle, __last,
4601 __gnu_cxx::__ops::__iter_comp_iter(__comp));
4602 }
4603
4604 /**
4605 * @brief Sort a sequence just enough to find a particular position.
4606 * @ingroup sorting_algorithms
4607 * @param __first An iterator.
4608 * @param __nth Another iterator.
4609 * @param __last Another iterator.
4610 * @return Nothing.
4611 *
4612 * Rearranges the elements in the range @p [__first,__last) so that @p *__nth
4613 * is the same element that would have been in that position had the
4614 * whole sequence been sorted. The elements either side of @p *__nth are
4615 * not completely sorted, but for any iterator @e i in the range
4616 * @p [__first,__nth) and any iterator @e j in the range @p [__nth,__last) it
4617 * holds that *j < *i is false.
4618 */
4619 template<typename _RandomAccessIterator>
4620 inline void
4621 nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth,
4622 _RandomAccessIterator __last)
4623 {
4624 // concept requirements
4625 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4626 _RandomAccessIterator>)
4627 __glibcxx_function_requires(_LessThanComparableConcept<
4628 typename iterator_traits<_RandomAccessIterator>::value_type>)
4629 __glibcxx_requires_valid_range(__first, __nth);
4630 __glibcxx_requires_valid_range(__nth, __last);
4631 __glibcxx_requires_irreflexive(__first, __last);
4632
4633 if (__first == __last || __nth == __last)
4634 return;
4635
4636 std::__introselect(__first, __nth, __last,
4637 std::__lg(__last - __first) * 2,
4638 __gnu_cxx::__ops::__iter_less_iter());
4639 }
4640
4641 /**
4642 * @brief Sort a sequence just enough to find a particular position
4643 * using a predicate for comparison.
4644 * @ingroup sorting_algorithms
4645 * @param __first An iterator.
4646 * @param __nth Another iterator.
4647 * @param __last Another iterator.
4648 * @param __comp A comparison functor.
4649 * @return Nothing.
4650 *
4651 * Rearranges the elements in the range @p [__first,__last) so that @p *__nth
4652 * is the same element that would have been in that position had the
4653 * whole sequence been sorted. The elements either side of @p *__nth are
4654 * not completely sorted, but for any iterator @e i in the range
4655 * @p [__first,__nth) and any iterator @e j in the range @p [__nth,__last) it
4656 * holds that @p __comp(*j,*i) is false.
4657 */
4658 template<typename _RandomAccessIterator, typename _Compare>
4659 inline void
4660 nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth,
4661 _RandomAccessIterator __last, _Compare __comp)
4662 {
4663 // concept requirements
4664 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4665 _RandomAccessIterator>)
4666 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
4667 typename iterator_traits<_RandomAccessIterator>::value_type,
4668 typename iterator_traits<_RandomAccessIterator>::value_type>)
4669 __glibcxx_requires_valid_range(__first, __nth);
4670 __glibcxx_requires_valid_range(__nth, __last);
4671 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
4672
4673 if (__first == __last || __nth == __last)
4674 return;
4675
4676 std::__introselect(__first, __nth, __last,
4677 std::__lg(__last - __first) * 2,
4678 __gnu_cxx::__ops::__iter_comp_iter(__comp));
4679 }
4680
4681 /**
4682 * @brief Sort the elements of a sequence.
4683 * @ingroup sorting_algorithms
4684 * @param __first An iterator.
4685 * @param __last Another iterator.
4686 * @return Nothing.
4687 *
4688 * Sorts the elements in the range @p [__first,__last) in ascending order,
4689 * such that for each iterator @e i in the range @p [__first,__last-1),
4690 * *(i+1)<*i is false.
4691 *
4692 * The relative ordering of equivalent elements is not preserved, use
4693 * @p stable_sort() if this is needed.
4694 */
4695 template<typename _RandomAccessIterator>
4696 inline void
4697 sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
4698 {
4699 // concept requirements
4700 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4701 _RandomAccessIterator>)
4702 __glibcxx_function_requires(_LessThanComparableConcept<
4703 typename iterator_traits<_RandomAccessIterator>::value_type>)
4704 __glibcxx_requires_valid_range(__first, __last);
4705 __glibcxx_requires_irreflexive(__first, __last);
4706
4707 std::__sort(__first, __last, __gnu_cxx::__ops::__iter_less_iter());
4708 }
4709
4710 /**
4711 * @brief Sort the elements of a sequence using a predicate for comparison.
4712 * @ingroup sorting_algorithms
4713 * @param __first An iterator.
4714 * @param __last Another iterator.
4715 * @param __comp A comparison functor.
4716 * @return Nothing.
4717 *
4718 * Sorts the elements in the range @p [__first,__last) in ascending order,
4719 * such that @p __comp(*(i+1),*i) is false for every iterator @e i in the
4720 * range @p [__first,__last-1).
4721 *
4722 * The relative ordering of equivalent elements is not preserved, use
4723 * @p stable_sort() if this is needed.
4724 */
4725 template<typename _RandomAccessIterator, typename _Compare>
4726 inline void
4727 sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
4728 _Compare __comp)
4729 {
4730 // concept requirements
4731 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4732 _RandomAccessIterator>)
4733 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
4734 typename iterator_traits<_RandomAccessIterator>::value_type,
4735 typename iterator_traits<_RandomAccessIterator>::value_type>)
4736 __glibcxx_requires_valid_range(__first, __last);
4737 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
4738
4739 std::__sort(__first, __last, __gnu_cxx::__ops::__iter_comp_iter(__comp));
4740 }
4741
4742 template<typename _InputIterator1, typename _InputIterator2,
4743 typename _OutputIterator, typename _Compare>
4744 _OutputIterator
4745 __merge(_InputIterator1 __first1, _InputIterator1 __last1,
4746 _InputIterator2 __first2, _InputIterator2 __last2,
4747 _OutputIterator __result, _Compare __comp)
4748 {
4749 while (__first1 != __last1 && __first2 != __last2)
4750 {
4751 if (__comp(__first2, __first1))
4752 {
4753 *__result = *__first2;
4754 ++__first2;
4755 }
4756 else
4757 {
4758 *__result = *__first1;
4759 ++__first1;
4760 }
4761 ++__result;
4762 }
4763 return std::copy(__first2, __last2,
4764 std::copy(__first1, __last1, __result));
4765 }
4766
4767 /**
4768 * @brief Merges two sorted ranges.
4769 * @ingroup sorting_algorithms
4770 * @param __first1 An iterator.
4771 * @param __first2 Another iterator.
4772 * @param __last1 Another iterator.
4773 * @param __last2 Another iterator.
4774 * @param __result An iterator pointing to the end of the merged range.
4775 * @return An iterator pointing to the first element <em>not less
4776 * than</em> @e val.
4777 *
4778 * Merges the ranges @p [__first1,__last1) and @p [__first2,__last2) into
4779 * the sorted range @p [__result, __result + (__last1-__first1) +
4780 * (__last2-__first2)). Both input ranges must be sorted, and the
4781 * output range must not overlap with either of the input ranges.
4782 * The sort is @e stable, that is, for equivalent elements in the
4783 * two ranges, elements from the first range will always come
4784 * before elements from the second.
4785 */
4786 template<typename _InputIterator1, typename _InputIterator2,
4787 typename _OutputIterator>
4788 inline _OutputIterator
4789 merge(_InputIterator1 __first1, _InputIterator1 __last1,
4790 _InputIterator2 __first2, _InputIterator2 __last2,
4791 _OutputIterator __result)
4792 {
4793 // concept requirements
4794 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
4795 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
4796 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4797 typename iterator_traits<_InputIterator1>::value_type>)
4798 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4799 typename iterator_traits<_InputIterator2>::value_type>)
4800 __glibcxx_function_requires(_LessThanOpConcept<
4801 typename iterator_traits<_InputIterator2>::value_type,
4802 typename iterator_traits<_InputIterator1>::value_type>)
4803 __glibcxx_requires_sorted_set(__first1, __last1, __first2);
4804 __glibcxx_requires_sorted_set(__first2, __last2, __first1);
4805 __glibcxx_requires_irreflexive2(__first1, __last1);
4806 __glibcxx_requires_irreflexive2(__first2, __last2);
4807
4808 return _GLIBCXX_STD_A::__merge(__first1, __last1,
4809 __first2, __last2, __result,
4810 __gnu_cxx::__ops::__iter_less_iter());
4811 }
4812
4813 /**
4814 * @brief Merges two sorted ranges.
4815 * @ingroup sorting_algorithms
4816 * @param __first1 An iterator.
4817 * @param __first2 Another iterator.
4818 * @param __last1 Another iterator.
4819 * @param __last2 Another iterator.
4820 * @param __result An iterator pointing to the end of the merged range.
4821 * @param __comp A functor to use for comparisons.
4822 * @return An iterator pointing to the first element "not less
4823 * than" @e val.
4824 *
4825 * Merges the ranges @p [__first1,__last1) and @p [__first2,__last2) into
4826 * the sorted range @p [__result, __result + (__last1-__first1) +
4827 * (__last2-__first2)). Both input ranges must be sorted, and the
4828 * output range must not overlap with either of the input ranges.
4829 * The sort is @e stable, that is, for equivalent elements in the
4830 * two ranges, elements from the first range will always come
4831 * before elements from the second.
4832 *
4833 * The comparison function should have the same effects on ordering as
4834 * the function used for the initial sort.
4835 */
4836 template<typename _InputIterator1, typename _InputIterator2,
4837 typename _OutputIterator, typename _Compare>
4838 inline _OutputIterator
4839 merge(_InputIterator1 __first1, _InputIterator1 __last1,
4840 _InputIterator2 __first2, _InputIterator2 __last2,
4841 _OutputIterator __result, _Compare __comp)
4842 {
4843 // concept requirements
4844 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
4845 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
4846 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4847 typename iterator_traits<_InputIterator1>::value_type>)
4848 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4849 typename iterator_traits<_InputIterator2>::value_type>)
4850 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
4851 typename iterator_traits<_InputIterator2>::value_type,
4852 typename iterator_traits<_InputIterator1>::value_type>)
4853 __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
4854 __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
4855 __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
4856 __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
4857
4858 return _GLIBCXX_STD_A::__merge(__first1, __last1,
4859 __first2, __last2, __result,
4860 __gnu_cxx::__ops::__iter_comp_iter(__comp));
4861 }
4862
4863 template<typename _RandomAccessIterator, typename _Compare>
4864 inline void
4865 __stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
4866 _Compare __comp)
4867 {
4868 typedef typename iterator_traits<_RandomAccessIterator>::value_type
4869 _ValueType;
4870 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
4871 _DistanceType;
4872
4873 typedef _Temporary_buffer<_RandomAccessIterator, _ValueType> _TmpBuf;
4874 _TmpBuf __buf(__first, __last);
4875
4876 if (__buf.begin() == 0)
4877 std::__inplace_stable_sort(__first, __last, __comp);
4878 else
4879 std::__stable_sort_adaptive(__first, __last, __buf.begin(),
4880 _DistanceType(__buf.size()), __comp);
4881 }
4882
4883 /**
4884 * @brief Sort the elements of a sequence, preserving the relative order
4885 * of equivalent elements.
4886 * @ingroup sorting_algorithms
4887 * @param __first An iterator.
4888 * @param __last Another iterator.
4889 * @return Nothing.
4890 *
4891 * Sorts the elements in the range @p [__first,__last) in ascending order,
4892 * such that for each iterator @p i in the range @p [__first,__last-1),
4893 * @p *(i+1)<*i is false.
4894 *
4895 * The relative ordering of equivalent elements is preserved, so any two
4896 * elements @p x and @p y in the range @p [__first,__last) such that
4897 * @p x<y is false and @p y<x is false will have the same relative
4898 * ordering after calling @p stable_sort().
4899 */
4900 template<typename _RandomAccessIterator>
4901 inline void
4902 stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
4903 {
4904 // concept requirements
4905 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4906 _RandomAccessIterator>)
4907 __glibcxx_function_requires(_LessThanComparableConcept<
4908 typename iterator_traits<_RandomAccessIterator>::value_type>)
4909 __glibcxx_requires_valid_range(__first, __last);
4910 __glibcxx_requires_irreflexive(__first, __last);
4911
4912 _GLIBCXX_STD_A::__stable_sort(__first, __last,
4913 __gnu_cxx::__ops::__iter_less_iter());
4914 }
4915
4916 /**
4917 * @brief Sort the elements of a sequence using a predicate for comparison,
4918 * preserving the relative order of equivalent elements.
4919 * @ingroup sorting_algorithms
4920 * @param __first An iterator.
4921 * @param __last Another iterator.
4922 * @param __comp A comparison functor.
4923 * @return Nothing.
4924 *
4925 * Sorts the elements in the range @p [__first,__last) in ascending order,
4926 * such that for each iterator @p i in the range @p [__first,__last-1),
4927 * @p __comp(*(i+1),*i) is false.
4928 *
4929 * The relative ordering of equivalent elements is preserved, so any two
4930 * elements @p x and @p y in the range @p [__first,__last) such that
4931 * @p __comp(x,y) is false and @p __comp(y,x) is false will have the same
4932 * relative ordering after calling @p stable_sort().
4933 */
4934 template<typename _RandomAccessIterator, typename _Compare>
4935 inline void
4936 stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
4937 _Compare __comp)
4938 {
4939 // concept requirements
4940 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4941 _RandomAccessIterator>)
4942 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
4943 typename iterator_traits<_RandomAccessIterator>::value_type,
4944 typename iterator_traits<_RandomAccessIterator>::value_type>)
4945 __glibcxx_requires_valid_range(__first, __last);
4946 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
4947
4948 _GLIBCXX_STD_A::__stable_sort(__first, __last,
4949 __gnu_cxx::__ops::__iter_comp_iter(__comp));
4950 }
4951
4952 template<typename _InputIterator1, typename _InputIterator2,
4953 typename _OutputIterator,
4954 typename _Compare>
4955 _OutputIterator
4956 __set_union(_InputIterator1 __first1, _InputIterator1 __last1,
4957 _InputIterator2 __first2, _InputIterator2 __last2,
4958 _OutputIterator __result, _Compare __comp)
4959 {
4960 while (__first1 != __last1 && __first2 != __last2)
4961 {
4962 if (__comp(__first1, __first2))
4963 {
4964 *__result = *__first1;
4965 ++__first1;
4966 }
4967 else if (__comp(__first2, __first1))
4968 {
4969 *__result = *__first2;
4970 ++__first2;
4971 }
4972 else
4973 {
4974 *__result = *__first1;
4975 ++__first1;
4976 ++__first2;
4977 }
4978 ++__result;
4979 }
4980 return std::copy(__first2, __last2,
4981 std::copy(__first1, __last1, __result));
4982 }
4983
4984 /**
4985 * @brief Return the union of two sorted ranges.
4986 * @ingroup set_algorithms
4987 * @param __first1 Start of first range.
4988 * @param __last1 End of first range.
4989 * @param __first2 Start of second range.
4990 * @param __last2 End of second range.
4991 * @return End of the output range.
4992 * @ingroup set_algorithms
4993 *
4994 * This operation iterates over both ranges, copying elements present in
4995 * each range in order to the output range. Iterators increment for each
4996 * range. When the current element of one range is less than the other,
4997 * that element is copied and the iterator advanced. If an element is
4998 * contained in both ranges, the element from the first range is copied and
4999 * both ranges advance. The output range may not overlap either input
5000 * range.
5001 */
5002 template<typename _InputIterator1, typename _InputIterator2,
5003 typename _OutputIterator>
5004 inline _OutputIterator
5005 set_union(_InputIterator1 __first1, _InputIterator1 __last1,
5006 _InputIterator2 __first2, _InputIterator2 __last2,
5007 _OutputIterator __result)
5008 {
5009 // concept requirements
5010 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5011 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5012 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5013 typename iterator_traits<_InputIterator1>::value_type>)
5014 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5015 typename iterator_traits<_InputIterator2>::value_type>)
5016 __glibcxx_function_requires(_LessThanOpConcept<
5017 typename iterator_traits<_InputIterator1>::value_type,
5018 typename iterator_traits<_InputIterator2>::value_type>)
5019 __glibcxx_function_requires(_LessThanOpConcept<
5020 typename iterator_traits<_InputIterator2>::value_type,
5021 typename iterator_traits<_InputIterator1>::value_type>)
5022 __glibcxx_requires_sorted_set(__first1, __last1, __first2);
5023 __glibcxx_requires_sorted_set(__first2, __last2, __first1);
5024 __glibcxx_requires_irreflexive2(__first1, __last1);
5025 __glibcxx_requires_irreflexive2(__first2, __last2);
5026
5027 return _GLIBCXX_STD_A::__set_union(__first1, __last1,
5028 __first2, __last2, __result,
5029 __gnu_cxx::__ops::__iter_less_iter());
5030 }
5031
5032 /**
5033 * @brief Return the union of two sorted ranges using a comparison functor.
5034 * @ingroup set_algorithms
5035 * @param __first1 Start of first range.
5036 * @param __last1 End of first range.
5037 * @param __first2 Start of second range.
5038 * @param __last2 End of second range.
5039 * @param __comp The comparison functor.
5040 * @return End of the output range.
5041 * @ingroup set_algorithms
5042 *
5043 * This operation iterates over both ranges, copying elements present in
5044 * each range in order to the output range. Iterators increment for each
5045 * range. When the current element of one range is less than the other
5046 * according to @p __comp, that element is copied and the iterator advanced.
5047 * If an equivalent element according to @p __comp is contained in both
5048 * ranges, the element from the first range is copied and both ranges
5049 * advance. The output range may not overlap either input range.
5050 */
5051 template<typename _InputIterator1, typename _InputIterator2,
5052 typename _OutputIterator, typename _Compare>
5053 inline _OutputIterator
5054 set_union(_InputIterator1 __first1, _InputIterator1 __last1,
5055 _InputIterator2 __first2, _InputIterator2 __last2,
5056 _OutputIterator __result, _Compare __comp)
5057 {
5058 // concept requirements
5059 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5060 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5061 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5062 typename iterator_traits<_InputIterator1>::value_type>)
5063 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5064 typename iterator_traits<_InputIterator2>::value_type>)
5065 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5066 typename iterator_traits<_InputIterator1>::value_type,
5067 typename iterator_traits<_InputIterator2>::value_type>)
5068 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5069 typename iterator_traits<_InputIterator2>::value_type,
5070 typename iterator_traits<_InputIterator1>::value_type>)
5071 __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
5072 __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
5073 __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
5074 __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
5075
5076 return _GLIBCXX_STD_A::__set_union(__first1, __last1,
5077 __first2, __last2, __result,
5078 __gnu_cxx::__ops::__iter_comp_iter(__comp));
5079 }
5080
5081 template<typename _InputIterator1, typename _InputIterator2,
5082 typename _OutputIterator,
5083 typename _Compare>
5084 _OutputIterator
5085 __set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
5086 _InputIterator2 __first2, _InputIterator2 __last2,
5087 _OutputIterator __result, _Compare __comp)
5088 {
5089 while (__first1 != __last1 && __first2 != __last2)
5090 if (__comp(__first1, __first2))
5091 ++__first1;
5092 else if (__comp(__first2, __first1))
5093 ++__first2;
5094 else
5095 {
5096 *__result = *__first1;
5097 ++__first1;
5098 ++__first2;
5099 ++__result;
5100 }
5101 return __result;
5102 }
5103
5104 /**
5105 * @brief Return the intersection of two sorted ranges.
5106 * @ingroup set_algorithms
5107 * @param __first1 Start of first range.
5108 * @param __last1 End of first range.
5109 * @param __first2 Start of second range.
5110 * @param __last2 End of second range.
5111 * @return End of the output range.
5112 * @ingroup set_algorithms
5113 *
5114 * This operation iterates over both ranges, copying elements present in
5115 * both ranges in order to the output range. Iterators increment for each
5116 * range. When the current element of one range is less than the other,
5117 * that iterator advances. If an element is contained in both ranges, the
5118 * element from the first range is copied and both ranges advance. The
5119 * output range may not overlap either input range.
5120 */
5121 template<typename _InputIterator1, typename _InputIterator2,
5122 typename _OutputIterator>
5123 inline _OutputIterator
5124 set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
5125 _InputIterator2 __first2, _InputIterator2 __last2,
5126 _OutputIterator __result)
5127 {
5128 // concept requirements
5129 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5130 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5131 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5132 typename iterator_traits<_InputIterator1>::value_type>)
5133 __glibcxx_function_requires(_LessThanOpConcept<
5134 typename iterator_traits<_InputIterator1>::value_type,
5135 typename iterator_traits<_InputIterator2>::value_type>)
5136 __glibcxx_function_requires(_LessThanOpConcept<
5137 typename iterator_traits<_InputIterator2>::value_type,
5138 typename iterator_traits<_InputIterator1>::value_type>)
5139 __glibcxx_requires_sorted_set(__first1, __last1, __first2);
5140 __glibcxx_requires_sorted_set(__first2, __last2, __first1);
5141 __glibcxx_requires_irreflexive2(__first1, __last1);
5142 __glibcxx_requires_irreflexive2(__first2, __last2);
5143
5144 return _GLIBCXX_STD_A::__set_intersection(__first1, __last1,
5145 __first2, __last2, __result,
5146 __gnu_cxx::__ops::__iter_less_iter());
5147 }
5148
5149 /**
5150 * @brief Return the intersection of two sorted ranges using comparison
5151 * functor.
5152 * @ingroup set_algorithms
5153 * @param __first1 Start of first range.
5154 * @param __last1 End of first range.
5155 * @param __first2 Start of second range.
5156 * @param __last2 End of second range.
5157 * @param __comp The comparison functor.
5158 * @return End of the output range.
5159 * @ingroup set_algorithms
5160 *
5161 * This operation iterates over both ranges, copying elements present in
5162 * both ranges in order to the output range. Iterators increment for each
5163 * range. When the current element of one range is less than the other
5164 * according to @p __comp, that iterator advances. If an element is
5165 * contained in both ranges according to @p __comp, the element from the
5166 * first range is copied and both ranges advance. The output range may not
5167 * overlap either input range.
5168 */
5169 template<typename _InputIterator1, typename _InputIterator2,
5170 typename _OutputIterator, typename _Compare>
5171 inline _OutputIterator
5172 set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
5173 _InputIterator2 __first2, _InputIterator2 __last2,
5174 _OutputIterator __result, _Compare __comp)
5175 {
5176 // concept requirements
5177 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5178 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5179 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5180 typename iterator_traits<_InputIterator1>::value_type>)
5181 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5182 typename iterator_traits<_InputIterator1>::value_type,
5183 typename iterator_traits<_InputIterator2>::value_type>)
5184 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5185 typename iterator_traits<_InputIterator2>::value_type,
5186 typename iterator_traits<_InputIterator1>::value_type>)
5187 __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
5188 __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
5189 __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
5190 __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
5191
5192 return _GLIBCXX_STD_A::__set_intersection(__first1, __last1,
5193 __first2, __last2, __result,
5194 __gnu_cxx::__ops::__iter_comp_iter(__comp));
5195 }
5196
5197 template<typename _InputIterator1, typename _InputIterator2,
5198 typename _OutputIterator,
5199 typename _Compare>
5200 _OutputIterator
5201 __set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5202 _InputIterator2 __first2, _InputIterator2 __last2,
5203 _OutputIterator __result, _Compare __comp)
5204 {
5205 while (__first1 != __last1 && __first2 != __last2)
5206 if (__comp(__first1, __first2))
5207 {
5208 *__result = *__first1;
5209 ++__first1;
5210 ++__result;
5211 }
5212 else if (__comp(__first2, __first1))
5213 ++__first2;
5214 else
5215 {
5216 ++__first1;
5217 ++__first2;
5218 }
5219 return std::copy(__first1, __last1, __result);
5220 }
5221
5222 /**
5223 * @brief Return the difference of two sorted ranges.
5224 * @ingroup set_algorithms
5225 * @param __first1 Start of first range.
5226 * @param __last1 End of first range.
5227 * @param __first2 Start of second range.
5228 * @param __last2 End of second range.
5229 * @return End of the output range.
5230 * @ingroup set_algorithms
5231 *
5232 * This operation iterates over both ranges, copying elements present in
5233 * the first range but not the second in order to the output range.
5234 * Iterators increment for each range. When the current element of the
5235 * first range is less than the second, that element is copied and the
5236 * iterator advances. If the current element of the second range is less,
5237 * the iterator advances, but no element is copied. If an element is
5238 * contained in both ranges, no elements are copied and both ranges
5239 * advance. The output range may not overlap either input range.
5240 */
5241 template<typename _InputIterator1, typename _InputIterator2,
5242 typename _OutputIterator>
5243 inline _OutputIterator
5244 set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5245 _InputIterator2 __first2, _InputIterator2 __last2,
5246 _OutputIterator __result)
5247 {
5248 // concept requirements
5249 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5250 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5251 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5252 typename iterator_traits<_InputIterator1>::value_type>)
5253 __glibcxx_function_requires(_LessThanOpConcept<
5254 typename iterator_traits<_InputIterator1>::value_type,
5255 typename iterator_traits<_InputIterator2>::value_type>)
5256 __glibcxx_function_requires(_LessThanOpConcept<
5257 typename iterator_traits<_InputIterator2>::value_type,
5258 typename iterator_traits<_InputIterator1>::value_type>)
5259 __glibcxx_requires_sorted_set(__first1, __last1, __first2);
5260 __glibcxx_requires_sorted_set(__first2, __last2, __first1);
5261 __glibcxx_requires_irreflexive2(__first1, __last1);
5262 __glibcxx_requires_irreflexive2(__first2, __last2);
5263
5264 return _GLIBCXX_STD_A::__set_difference(__first1, __last1,
5265 __first2, __last2, __result,
5266 __gnu_cxx::__ops::__iter_less_iter());
5267 }
5268
5269 /**
5270 * @brief Return the difference of two sorted ranges using comparison
5271 * functor.
5272 * @ingroup set_algorithms
5273 * @param __first1 Start of first range.
5274 * @param __last1 End of first range.
5275 * @param __first2 Start of second range.
5276 * @param __last2 End of second range.
5277 * @param __comp The comparison functor.
5278 * @return End of the output range.
5279 * @ingroup set_algorithms
5280 *
5281 * This operation iterates over both ranges, copying elements present in
5282 * the first range but not the second in order to the output range.
5283 * Iterators increment for each range. When the current element of the
5284 * first range is less than the second according to @p __comp, that element
5285 * is copied and the iterator advances. If the current element of the
5286 * second range is less, no element is copied and the iterator advances.
5287 * If an element is contained in both ranges according to @p __comp, no
5288 * elements are copied and both ranges advance. The output range may not
5289 * overlap either input range.
5290 */
5291 template<typename _InputIterator1, typename _InputIterator2,
5292 typename _OutputIterator, typename _Compare>
5293 inline _OutputIterator
5294 set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5295 _InputIterator2 __first2, _InputIterator2 __last2,
5296 _OutputIterator __result, _Compare __comp)
5297 {
5298 // concept requirements
5299 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5300 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5301 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5302 typename iterator_traits<_InputIterator1>::value_type>)
5303 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5304 typename iterator_traits<_InputIterator1>::value_type,
5305 typename iterator_traits<_InputIterator2>::value_type>)
5306 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5307 typename iterator_traits<_InputIterator2>::value_type,
5308 typename iterator_traits<_InputIterator1>::value_type>)
5309 __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
5310 __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
5311 __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
5312 __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
5313
5314 return _GLIBCXX_STD_A::__set_difference(__first1, __last1,
5315 __first2, __last2, __result,
5316 __gnu_cxx::__ops::__iter_comp_iter(__comp));
5317 }
5318
5319 template<typename _InputIterator1, typename _InputIterator2,
5320 typename _OutputIterator,
5321 typename _Compare>
5322 _OutputIterator
5323 __set_symmetric_difference(_InputIterator1 __first1,
5324 _InputIterator1 __last1,
5325 _InputIterator2 __first2,
5326 _InputIterator2 __last2,
5327 _OutputIterator __result,
5328 _Compare __comp)
5329 {
5330 while (__first1 != __last1 && __first2 != __last2)
5331 if (__comp(__first1, __first2))
5332 {
5333 *__result = *__first1;
5334 ++__first1;
5335 ++__result;
5336 }
5337 else if (__comp(__first2, __first1))
5338 {
5339 *__result = *__first2;
5340 ++__first2;
5341 ++__result;
5342 }
5343 else
5344 {
5345 ++__first1;
5346 ++__first2;
5347 }
5348 return std::copy(__first2, __last2,
5349 std::copy(__first1, __last1, __result));
5350 }
5351
5352 /**
5353 * @brief Return the symmetric difference of two sorted ranges.
5354 * @ingroup set_algorithms
5355 * @param __first1 Start of first range.
5356 * @param __last1 End of first range.
5357 * @param __first2 Start of second range.
5358 * @param __last2 End of second range.
5359 * @return End of the output range.
5360 * @ingroup set_algorithms
5361 *
5362 * This operation iterates over both ranges, copying elements present in
5363 * one range but not the other in order to the output range. Iterators
5364 * increment for each range. When the current element of one range is less
5365 * than the other, that element is copied and the iterator advances. If an
5366 * element is contained in both ranges, no elements are copied and both
5367 * ranges advance. The output range may not overlap either input range.
5368 */
5369 template<typename _InputIterator1, typename _InputIterator2,
5370 typename _OutputIterator>
5371 inline _OutputIterator
5372 set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5373 _InputIterator2 __first2, _InputIterator2 __last2,
5374 _OutputIterator __result)
5375 {
5376 // concept requirements
5377 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5378 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5379 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5380 typename iterator_traits<_InputIterator1>::value_type>)
5381 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5382 typename iterator_traits<_InputIterator2>::value_type>)
5383 __glibcxx_function_requires(_LessThanOpConcept<
5384 typename iterator_traits<_InputIterator1>::value_type,
5385 typename iterator_traits<_InputIterator2>::value_type>)
5386 __glibcxx_function_requires(_LessThanOpConcept<
5387 typename iterator_traits<_InputIterator2>::value_type,
5388 typename iterator_traits<_InputIterator1>::value_type>)
5389 __glibcxx_requires_sorted_set(__first1, __last1, __first2);
5390 __glibcxx_requires_sorted_set(__first2, __last2, __first1);
5391 __glibcxx_requires_irreflexive2(__first1, __last1);
5392 __glibcxx_requires_irreflexive2(__first2, __last2);
5393
5394 return _GLIBCXX_STD_A::__set_symmetric_difference(__first1, __last1,
5395 __first2, __last2, __result,
5396 __gnu_cxx::__ops::__iter_less_iter());
5397 }
5398
5399 /**
5400 * @brief Return the symmetric difference of two sorted ranges using
5401 * comparison functor.
5402 * @ingroup set_algorithms
5403 * @param __first1 Start of first range.
5404 * @param __last1 End of first range.
5405 * @param __first2 Start of second range.
5406 * @param __last2 End of second range.
5407 * @param __comp The comparison functor.
5408 * @return End of the output range.
5409 * @ingroup set_algorithms
5410 *
5411 * This operation iterates over both ranges, copying elements present in
5412 * one range but not the other in order to the output range. Iterators
5413 * increment for each range. When the current element of one range is less
5414 * than the other according to @p comp, that element is copied and the
5415 * iterator advances. If an element is contained in both ranges according
5416 * to @p __comp, no elements are copied and both ranges advance. The output
5417 * range may not overlap either input range.
5418 */
5419 template<typename _InputIterator1, typename _InputIterator2,
5420 typename _OutputIterator, typename _Compare>
5421 inline _OutputIterator
5422 set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5423 _InputIterator2 __first2, _InputIterator2 __last2,
5424 _OutputIterator __result,
5425 _Compare __comp)
5426 {
5427 // concept requirements
5428 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5429 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5430 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5431 typename iterator_traits<_InputIterator1>::value_type>)
5432 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5433 typename iterator_traits<_InputIterator2>::value_type>)
5434 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5435 typename iterator_traits<_InputIterator1>::value_type,
5436 typename iterator_traits<_InputIterator2>::value_type>)
5437 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5438 typename iterator_traits<_InputIterator2>::value_type,
5439 typename iterator_traits<_InputIterator1>::value_type>)
5440 __glibcxx_requires_sorted_set_pred(__first1, __last1, __first2, __comp);
5441 __glibcxx_requires_sorted_set_pred(__first2, __last2, __first1, __comp);
5442 __glibcxx_requires_irreflexive_pred2(__first1, __last1, __comp);
5443 __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
5444
5445 return _GLIBCXX_STD_A::__set_symmetric_difference(__first1, __last1,
5446 __first2, __last2, __result,
5447 __gnu_cxx::__ops::__iter_comp_iter(__comp));
5448 }
5449
5450 template<typename _ForwardIterator, typename _Compare>
5451 _GLIBCXX14_CONSTEXPR
5452 _ForwardIterator
5453 __min_element(_ForwardIterator __first, _ForwardIterator __last,
5454 _Compare __comp)
5455 {
5456 if (__first == __last)
5457 return __first;
5458 _ForwardIterator __result = __first;
5459 while (++__first != __last)
5460 if (__comp(__first, __result))
5461 __result = __first;
5462 return __result;
5463 }
5464
5465 /**
5466 * @brief Return the minimum element in a range.
5467 * @ingroup sorting_algorithms
5468 * @param __first Start of range.
5469 * @param __last End of range.
5470 * @return Iterator referencing the first instance of the smallest value.
5471 */
5472 template<typename _ForwardIterator>
5473 _GLIBCXX14_CONSTEXPR
5474 _ForwardIterator
5475 inline min_element(_ForwardIterator __first, _ForwardIterator __last)
5476 {
5477 // concept requirements
5478 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
5479 __glibcxx_function_requires(_LessThanComparableConcept<
5480 typename iterator_traits<_ForwardIterator>::value_type>)
5481 __glibcxx_requires_valid_range(__first, __last);
5482 __glibcxx_requires_irreflexive(__first, __last);
5483
5484 return _GLIBCXX_STD_A::__min_element(__first, __last,
5485 __gnu_cxx::__ops::__iter_less_iter());
5486 }
5487
5488 /**
5489 * @brief Return the minimum element in a range using comparison functor.
5490 * @ingroup sorting_algorithms
5491 * @param __first Start of range.
5492 * @param __last End of range.
5493 * @param __comp Comparison functor.
5494 * @return Iterator referencing the first instance of the smallest value
5495 * according to __comp.
5496 */
5497 template<typename _ForwardIterator, typename _Compare>
5498 _GLIBCXX14_CONSTEXPR
5499 inline _ForwardIterator
5500 min_element(_ForwardIterator __first, _ForwardIterator __last,
5501 _Compare __comp)
5502 {
5503 // concept requirements
5504 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
5505 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5506 typename iterator_traits<_ForwardIterator>::value_type,
5507 typename iterator_traits<_ForwardIterator>::value_type>)
5508 __glibcxx_requires_valid_range(__first, __last);
5509 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
5510
5511 return _GLIBCXX_STD_A::__min_element(__first, __last,
5512 __gnu_cxx::__ops::__iter_comp_iter(__comp));
5513 }
5514
5515 template<typename _ForwardIterator, typename _Compare>
5516 _GLIBCXX14_CONSTEXPR
5517 _ForwardIterator
5518 __max_element(_ForwardIterator __first, _ForwardIterator __last,
5519 _Compare __comp)
5520 {
5521 if (__first == __last) return __first;
5522 _ForwardIterator __result = __first;
5523 while (++__first != __last)
5524 if (__comp(__result, __first))
5525 __result = __first;
5526 return __result;
5527 }
5528
5529 /**
5530 * @brief Return the maximum element in a range.
5531 * @ingroup sorting_algorithms
5532 * @param __first Start of range.
5533 * @param __last End of range.
5534 * @return Iterator referencing the first instance of the largest value.
5535 */
5536 template<typename _ForwardIterator>
5537 _GLIBCXX14_CONSTEXPR
5538 inline _ForwardIterator
5539 max_element(_ForwardIterator __first, _ForwardIterator __last)
5540 {
5541 // concept requirements
5542 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
5543 __glibcxx_function_requires(_LessThanComparableConcept<
5544 typename iterator_traits<_ForwardIterator>::value_type>)
5545 __glibcxx_requires_valid_range(__first, __last);
5546 __glibcxx_requires_irreflexive(__first, __last);
5547
5548 return _GLIBCXX_STD_A::__max_element(__first, __last,
5549 __gnu_cxx::__ops::__iter_less_iter());
5550 }
5551
5552 /**
5553 * @brief Return the maximum element in a range using comparison functor.
5554 * @ingroup sorting_algorithms
5555 * @param __first Start of range.
5556 * @param __last End of range.
5557 * @param __comp Comparison functor.
5558 * @return Iterator referencing the first instance of the largest value
5559 * according to __comp.
5560 */
5561 template<typename _ForwardIterator, typename _Compare>
5562 _GLIBCXX14_CONSTEXPR
5563 inline _ForwardIterator
5564 max_element(_ForwardIterator __first, _ForwardIterator __last,
5565 _Compare __comp)
5566 {
5567 // concept requirements
5568 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
5569 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5570 typename iterator_traits<_ForwardIterator>::value_type,
5571 typename iterator_traits<_ForwardIterator>::value_type>)
5572 __glibcxx_requires_valid_range(__first, __last);
5573 __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
5574
5575 return _GLIBCXX_STD_A::__max_element(__first, __last,
5576 __gnu_cxx::__ops::__iter_comp_iter(__comp));
5577 }
5578
5579 _GLIBCXX_END_NAMESPACE_ALGO
5580 } // namespace std
5581
5582 #endif /* _STL_ALGO_H */
5583