1 // Multimap implementation -*- C++ -*-
2
3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
4 // 2011, 2012 Free Software Foundation, Inc.
5 //
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 3, or (at your option)
10 // any later version.
11
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16
17 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
20
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
25
26 /*
27 *
28 * Copyright (c) 1994
29 * Hewlett-Packard Company
30 *
31 * Permission to use, copy, modify, distribute and sell this software
32 * and its documentation for any purpose is hereby granted without fee,
33 * provided that the above copyright notice appear in all copies and
34 * that both that copyright notice and this permission notice appear
35 * in supporting documentation. Hewlett-Packard Company makes no
36 * representations about the suitability of this software for any
37 * purpose. It is provided "as is" without express or implied warranty.
38 *
39 *
40 * Copyright (c) 1996,1997
41 * Silicon Graphics Computer Systems, Inc.
42 *
43 * Permission to use, copy, modify, distribute and sell this software
44 * and its documentation for any purpose is hereby granted without fee,
45 * provided that the above copyright notice appear in all copies and
46 * that both that copyright notice and this permission notice appear
47 * in supporting documentation. Silicon Graphics makes no
48 * representations about the suitability of this software for any
49 * purpose. It is provided "as is" without express or implied warranty.
50 */
51
52 /** @file bits/stl_multimap.h
53 * This is an internal header file, included by other library headers.
54 * Do not attempt to use it directly. @headername{map}
55 */
56
57 #ifndef _STL_MULTIMAP_H
58 #define _STL_MULTIMAP_H 1
59
60 #include <bits/concept_check.h>
61 #ifdef __GXX_EXPERIMENTAL_CXX0X__
62 #include <initializer_list>
63 #endif
64
_GLIBCXX_VISIBILITY(default)65 namespace std _GLIBCXX_VISIBILITY(default)
66 {
67 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
68
69 /**
70 * @brief A standard container made up of (key,value) pairs, which can be
71 * retrieved based on a key, in logarithmic time.
72 *
73 * @ingroup associative_containers
74 *
75 * Meets the requirements of a <a href="tables.html#65">container</a>, a
76 * <a href="tables.html#66">reversible container</a>, and an
77 * <a href="tables.html#69">associative container</a> (using equivalent
78 * keys). For a @c multimap<Key,T> the key_type is Key, the mapped_type
79 * is T, and the value_type is std::pair<const Key,T>.
80 *
81 * Multimaps support bidirectional iterators.
82 *
83 * The private tree data is declared exactly the same way for map and
84 * multimap; the distinction is made entirely in how the tree functions are
85 * called (*_unique versus *_equal, same as the standard).
86 */
87 template <typename _Key, typename _Tp,
88 typename _Compare = std::less<_Key>,
89 typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
90 class multimap
91 {
92 public:
93 typedef _Key key_type;
94 typedef _Tp mapped_type;
95 typedef std::pair<const _Key, _Tp> value_type;
96 typedef _Compare key_compare;
97 typedef _Alloc allocator_type;
98
99 private:
100 // concept requirements
101 typedef typename _Alloc::value_type _Alloc_value_type;
102 __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
103 __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
104 _BinaryFunctionConcept)
105 __glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept)
106
107 public:
108 class value_compare
109 : public std::binary_function<value_type, value_type, bool>
110 {
111 friend class multimap<_Key, _Tp, _Compare, _Alloc>;
112 protected:
113 _Compare comp;
114
115 value_compare(_Compare __c)
116 : comp(__c) { }
117
118 public:
119 bool operator()(const value_type& __x, const value_type& __y) const
120 { return comp(__x.first, __y.first); }
121 };
122
123 private:
124 /// This turns a red-black tree into a [multi]map.
125 typedef typename _Alloc::template rebind<value_type>::other
126 _Pair_alloc_type;
127
128 typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
129 key_compare, _Pair_alloc_type> _Rep_type;
130 /// The actual tree structure.
131 _Rep_type _M_t;
132
133 public:
134 // many of these are specified differently in ISO, but the following are
135 // "functionally equivalent"
136 typedef typename _Pair_alloc_type::pointer pointer;
137 typedef typename _Pair_alloc_type::const_pointer const_pointer;
138 typedef typename _Pair_alloc_type::reference reference;
139 typedef typename _Pair_alloc_type::const_reference const_reference;
140 typedef typename _Rep_type::iterator iterator;
141 typedef typename _Rep_type::const_iterator const_iterator;
142 typedef typename _Rep_type::size_type size_type;
143 typedef typename _Rep_type::difference_type difference_type;
144 typedef typename _Rep_type::reverse_iterator reverse_iterator;
145 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
146
147 // [23.3.2] construct/copy/destroy
148 // (get_allocator() is also listed in this section)
149 /**
150 * @brief Default constructor creates no elements.
151 */
152 multimap()
153 : _M_t() { }
154
155 /**
156 * @brief Creates a %multimap with no elements.
157 * @param __comp A comparison object.
158 * @param __a An allocator object.
159 */
160 explicit
161 multimap(const _Compare& __comp,
162 const allocator_type& __a = allocator_type())
163 : _M_t(__comp, _Pair_alloc_type(__a)) { }
164
165 /**
166 * @brief %Multimap copy constructor.
167 * @param __x A %multimap of identical element and allocator types.
168 *
169 * The newly-created %multimap uses a copy of the allocation object
170 * used by @a __x.
171 */
172 multimap(const multimap& __x)
173 : _M_t(__x._M_t) { }
174
175 #ifdef __GXX_EXPERIMENTAL_CXX0X__
176 /**
177 * @brief %Multimap move constructor.
178 * @param __x A %multimap of identical element and allocator types.
179 *
180 * The newly-created %multimap contains the exact contents of @a __x.
181 * The contents of @a __x are a valid, but unspecified %multimap.
182 */
183 multimap(multimap&& __x)
184 noexcept(is_nothrow_copy_constructible<_Compare>::value)
185 : _M_t(std::move(__x._M_t)) { }
186
187 /**
188 * @brief Builds a %multimap from an initializer_list.
189 * @param __l An initializer_list.
190 * @param __comp A comparison functor.
191 * @param __a An allocator object.
192 *
193 * Create a %multimap consisting of copies of the elements from
194 * the initializer_list. This is linear in N if the list is already
195 * sorted, and NlogN otherwise (where N is @a __l.size()).
196 */
197 multimap(initializer_list<value_type> __l,
198 const _Compare& __comp = _Compare(),
199 const allocator_type& __a = allocator_type())
200 : _M_t(__comp, _Pair_alloc_type(__a))
201 { _M_t._M_insert_equal(__l.begin(), __l.end()); }
202 #endif
203
204 /**
205 * @brief Builds a %multimap from a range.
206 * @param __first An input iterator.
207 * @param __last An input iterator.
208 *
209 * Create a %multimap consisting of copies of the elements from
210 * [__first,__last). This is linear in N if the range is already sorted,
211 * and NlogN otherwise (where N is distance(__first,__last)).
212 */
213 template<typename _InputIterator>
214 multimap(_InputIterator __first, _InputIterator __last)
215 : _M_t()
216 { _M_t._M_insert_equal(__first, __last); }
217
218 /**
219 * @brief Builds a %multimap from a range.
220 * @param __first An input iterator.
221 * @param __last An input iterator.
222 * @param __comp A comparison functor.
223 * @param __a An allocator object.
224 *
225 * Create a %multimap consisting of copies of the elements from
226 * [__first,__last). This is linear in N if the range is already sorted,
227 * and NlogN otherwise (where N is distance(__first,__last)).
228 */
229 template<typename _InputIterator>
230 multimap(_InputIterator __first, _InputIterator __last,
231 const _Compare& __comp,
232 const allocator_type& __a = allocator_type())
233 : _M_t(__comp, _Pair_alloc_type(__a))
234 { _M_t._M_insert_equal(__first, __last); }
235
236 // FIXME There is no dtor declared, but we should have something generated
237 // by Doxygen. I don't know what tags to add to this paragraph to make
238 // that happen:
239 /**
240 * The dtor only erases the elements, and note that if the elements
241 * themselves are pointers, the pointed-to memory is not touched in any
242 * way. Managing the pointer is the user's responsibility.
243 */
244
245 /**
246 * @brief %Multimap assignment operator.
247 * @param __x A %multimap of identical element and allocator types.
248 *
249 * All the elements of @a __x are copied, but unlike the copy
250 * constructor, the allocator object is not copied.
251 */
252 multimap&
253 operator=(const multimap& __x)
254 {
255 _M_t = __x._M_t;
256 return *this;
257 }
258
259 #ifdef __GXX_EXPERIMENTAL_CXX0X__
260 /**
261 * @brief %Multimap move assignment operator.
262 * @param __x A %multimap of identical element and allocator types.
263 *
264 * The contents of @a __x are moved into this multimap (without copying).
265 * @a __x is a valid, but unspecified multimap.
266 */
267 multimap&
268 operator=(multimap&& __x)
269 {
270 // NB: DR 1204.
271 // NB: DR 675.
272 this->clear();
273 this->swap(__x);
274 return *this;
275 }
276
277 /**
278 * @brief %Multimap list assignment operator.
279 * @param __l An initializer_list.
280 *
281 * This function fills a %multimap with copies of the elements
282 * in the initializer list @a __l.
283 *
284 * Note that the assignment completely changes the %multimap and
285 * that the resulting %multimap's size is the same as the number
286 * of elements assigned. Old data may be lost.
287 */
288 multimap&
289 operator=(initializer_list<value_type> __l)
290 {
291 this->clear();
292 this->insert(__l.begin(), __l.end());
293 return *this;
294 }
295 #endif
296
297 /// Get a copy of the memory allocation object.
298 allocator_type
299 get_allocator() const _GLIBCXX_NOEXCEPT
300 { return allocator_type(_M_t.get_allocator()); }
301
302 // iterators
303 /**
304 * Returns a read/write iterator that points to the first pair in the
305 * %multimap. Iteration is done in ascending order according to the
306 * keys.
307 */
308 iterator
309 begin() _GLIBCXX_NOEXCEPT
310 { return _M_t.begin(); }
311
312 /**
313 * Returns a read-only (constant) iterator that points to the first pair
314 * in the %multimap. Iteration is done in ascending order according to
315 * the keys.
316 */
317 const_iterator
318 begin() const _GLIBCXX_NOEXCEPT
319 { return _M_t.begin(); }
320
321 /**
322 * Returns a read/write iterator that points one past the last pair in
323 * the %multimap. Iteration is done in ascending order according to the
324 * keys.
325 */
326 iterator
327 end() _GLIBCXX_NOEXCEPT
328 { return _M_t.end(); }
329
330 /**
331 * Returns a read-only (constant) iterator that points one past the last
332 * pair in the %multimap. Iteration is done in ascending order according
333 * to the keys.
334 */
335 const_iterator
336 end() const _GLIBCXX_NOEXCEPT
337 { return _M_t.end(); }
338
339 /**
340 * Returns a read/write reverse iterator that points to the last pair in
341 * the %multimap. Iteration is done in descending order according to the
342 * keys.
343 */
344 reverse_iterator
345 rbegin() _GLIBCXX_NOEXCEPT
346 { return _M_t.rbegin(); }
347
348 /**
349 * Returns a read-only (constant) reverse iterator that points to the
350 * last pair in the %multimap. Iteration is done in descending order
351 * according to the keys.
352 */
353 const_reverse_iterator
354 rbegin() const _GLIBCXX_NOEXCEPT
355 { return _M_t.rbegin(); }
356
357 /**
358 * Returns a read/write reverse iterator that points to one before the
359 * first pair in the %multimap. Iteration is done in descending order
360 * according to the keys.
361 */
362 reverse_iterator
363 rend() _GLIBCXX_NOEXCEPT
364 { return _M_t.rend(); }
365
366 /**
367 * Returns a read-only (constant) reverse iterator that points to one
368 * before the first pair in the %multimap. Iteration is done in
369 * descending order according to the keys.
370 */
371 const_reverse_iterator
372 rend() const _GLIBCXX_NOEXCEPT
373 { return _M_t.rend(); }
374
375 #ifdef __GXX_EXPERIMENTAL_CXX0X__
376 /**
377 * Returns a read-only (constant) iterator that points to the first pair
378 * in the %multimap. Iteration is done in ascending order according to
379 * the keys.
380 */
381 const_iterator
382 cbegin() const noexcept
383 { return _M_t.begin(); }
384
385 /**
386 * Returns a read-only (constant) iterator that points one past the last
387 * pair in the %multimap. Iteration is done in ascending order according
388 * to the keys.
389 */
390 const_iterator
391 cend() const noexcept
392 { return _M_t.end(); }
393
394 /**
395 * Returns a read-only (constant) reverse iterator that points to the
396 * last pair in the %multimap. Iteration is done in descending order
397 * according to the keys.
398 */
399 const_reverse_iterator
400 crbegin() const noexcept
401 { return _M_t.rbegin(); }
402
403 /**
404 * Returns a read-only (constant) reverse iterator that points to one
405 * before the first pair in the %multimap. Iteration is done in
406 * descending order according to the keys.
407 */
408 const_reverse_iterator
409 crend() const noexcept
410 { return _M_t.rend(); }
411 #endif
412
413 // capacity
414 /** Returns true if the %multimap is empty. */
415 bool
416 empty() const _GLIBCXX_NOEXCEPT
417 { return _M_t.empty(); }
418
419 /** Returns the size of the %multimap. */
420 size_type
421 size() const _GLIBCXX_NOEXCEPT
422 { return _M_t.size(); }
423
424 /** Returns the maximum size of the %multimap. */
425 size_type
426 max_size() const _GLIBCXX_NOEXCEPT
427 { return _M_t.max_size(); }
428
429 // modifiers
430 /**
431 * @brief Inserts a std::pair into the %multimap.
432 * @param __x Pair to be inserted (see std::make_pair for easy creation
433 * of pairs).
434 * @return An iterator that points to the inserted (key,value) pair.
435 *
436 * This function inserts a (key, value) pair into the %multimap.
437 * Contrary to a std::map the %multimap does not rely on unique keys and
438 * thus multiple pairs with the same key can be inserted.
439 *
440 * Insertion requires logarithmic time.
441 */
442 iterator
443 insert(const value_type& __x)
444 { return _M_t._M_insert_equal(__x); }
445
446 #ifdef __GXX_EXPERIMENTAL_CXX0X__
447 template<typename _Pair, typename = typename
448 std::enable_if<std::is_constructible<value_type,
449 _Pair&&>::value>::type>
450 iterator
451 insert(_Pair&& __x)
452 { return _M_t._M_insert_equal(std::forward<_Pair>(__x)); }
453 #endif
454
455 /**
456 * @brief Inserts a std::pair into the %multimap.
457 * @param __position An iterator that serves as a hint as to where the
458 * pair should be inserted.
459 * @param __x Pair to be inserted (see std::make_pair for easy creation
460 * of pairs).
461 * @return An iterator that points to the inserted (key,value) pair.
462 *
463 * This function inserts a (key, value) pair into the %multimap.
464 * Contrary to a std::map the %multimap does not rely on unique keys and
465 * thus multiple pairs with the same key can be inserted.
466 * Note that the first parameter is only a hint and can potentially
467 * improve the performance of the insertion process. A bad hint would
468 * cause no gains in efficiency.
469 *
470 * For more on @a hinting, see:
471 * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
472 *
473 * Insertion requires logarithmic time (if the hint is not taken).
474 */
475 iterator
476 #ifdef __GXX_EXPERIMENTAL_CXX0X__
477 insert(const_iterator __position, const value_type& __x)
478 #else
479 insert(iterator __position, const value_type& __x)
480 #endif
481 { return _M_t._M_insert_equal_(__position, __x); }
482
483 #ifdef __GXX_EXPERIMENTAL_CXX0X__
484 template<typename _Pair, typename = typename
485 std::enable_if<std::is_constructible<value_type,
486 _Pair&&>::value>::type>
487 iterator
488 insert(const_iterator __position, _Pair&& __x)
489 { return _M_t._M_insert_equal_(__position,
490 std::forward<_Pair>(__x)); }
491 #endif
492
493 /**
494 * @brief A template function that attempts to insert a range
495 * of elements.
496 * @param __first Iterator pointing to the start of the range to be
497 * inserted.
498 * @param __last Iterator pointing to the end of the range.
499 *
500 * Complexity similar to that of the range constructor.
501 */
502 template<typename _InputIterator>
503 void
504 insert(_InputIterator __first, _InputIterator __last)
505 { _M_t._M_insert_equal(__first, __last); }
506
507 #ifdef __GXX_EXPERIMENTAL_CXX0X__
508 /**
509 * @brief Attempts to insert a list of std::pairs into the %multimap.
510 * @param __l A std::initializer_list<value_type> of pairs to be
511 * inserted.
512 *
513 * Complexity similar to that of the range constructor.
514 */
515 void
516 insert(initializer_list<value_type> __l)
517 { this->insert(__l.begin(), __l.end()); }
518 #endif
519
520 #ifdef __GXX_EXPERIMENTAL_CXX0X__
521 // _GLIBCXX_RESOLVE_LIB_DEFECTS
522 // DR 130. Associative erase should return an iterator.
523 /**
524 * @brief Erases an element from a %multimap.
525 * @param __position An iterator pointing to the element to be erased.
526 * @return An iterator pointing to the element immediately following
527 * @a position prior to the element being erased. If no such
528 * element exists, end() is returned.
529 *
530 * This function erases an element, pointed to by the given iterator,
531 * from a %multimap. Note that this function only erases the element,
532 * and that if the element is itself a pointer, the pointed-to memory is
533 * not touched in any way. Managing the pointer is the user's
534 * responsibility.
535 */
536 iterator
537 erase(const_iterator __position)
538 { return _M_t.erase(__position); }
539
540 // LWG 2059.
541 iterator
542 erase(iterator __position)
543 { return _M_t.erase(__position); }
544 #else
545 /**
546 * @brief Erases an element from a %multimap.
547 * @param __position An iterator pointing to the element to be erased.
548 *
549 * This function erases an element, pointed to by the given iterator,
550 * from a %multimap. Note that this function only erases the element,
551 * and that if the element is itself a pointer, the pointed-to memory is
552 * not touched in any way. Managing the pointer is the user's
553 * responsibility.
554 */
555 void
556 erase(iterator __position)
557 { _M_t.erase(__position); }
558 #endif
559
560 /**
561 * @brief Erases elements according to the provided key.
562 * @param __x Key of element to be erased.
563 * @return The number of elements erased.
564 *
565 * This function erases all elements located by the given key from a
566 * %multimap.
567 * Note that this function only erases the element, and that if
568 * the element is itself a pointer, the pointed-to memory is not touched
569 * in any way. Managing the pointer is the user's responsibility.
570 */
571 size_type
572 erase(const key_type& __x)
573 { return _M_t.erase(__x); }
574
575 #ifdef __GXX_EXPERIMENTAL_CXX0X__
576 // _GLIBCXX_RESOLVE_LIB_DEFECTS
577 // DR 130. Associative erase should return an iterator.
578 /**
579 * @brief Erases a [first,last) range of elements from a %multimap.
580 * @param __first Iterator pointing to the start of the range to be
581 * erased.
582 * @param __last Iterator pointing to the end of the range to be
583 * erased .
584 * @return The iterator @a __last.
585 *
586 * This function erases a sequence of elements from a %multimap.
587 * Note that this function only erases the elements, and that if
588 * the elements themselves are pointers, the pointed-to memory is not
589 * touched in any way. Managing the pointer is the user's
590 * responsibility.
591 */
592 iterator
593 erase(const_iterator __first, const_iterator __last)
594 { return _M_t.erase(__first, __last); }
595 #else
596 // _GLIBCXX_RESOLVE_LIB_DEFECTS
597 // DR 130. Associative erase should return an iterator.
598 /**
599 * @brief Erases a [first,last) range of elements from a %multimap.
600 * @param __first Iterator pointing to the start of the range to be
601 * erased.
602 * @param __last Iterator pointing to the end of the range to
603 * be erased.
604 *
605 * This function erases a sequence of elements from a %multimap.
606 * Note that this function only erases the elements, and that if
607 * the elements themselves are pointers, the pointed-to memory is not
608 * touched in any way. Managing the pointer is the user's
609 * responsibility.
610 */
611 void
612 erase(iterator __first, iterator __last)
613 { _M_t.erase(__first, __last); }
614 #endif
615
616 /**
617 * @brief Swaps data with another %multimap.
618 * @param __x A %multimap of the same element and allocator types.
619 *
620 * This exchanges the elements between two multimaps in constant time.
621 * (It is only swapping a pointer, an integer, and an instance of
622 * the @c Compare type (which itself is often stateless and empty), so it
623 * should be quite fast.)
624 * Note that the global std::swap() function is specialized such that
625 * std::swap(m1,m2) will feed to this function.
626 */
627 void
628 swap(multimap& __x)
629 { _M_t.swap(__x._M_t); }
630
631 /**
632 * Erases all elements in a %multimap. Note that this function only
633 * erases the elements, and that if the elements themselves are pointers,
634 * the pointed-to memory is not touched in any way. Managing the pointer
635 * is the user's responsibility.
636 */
637 void
638 clear() _GLIBCXX_NOEXCEPT
639 { _M_t.clear(); }
640
641 // observers
642 /**
643 * Returns the key comparison object out of which the %multimap
644 * was constructed.
645 */
646 key_compare
647 key_comp() const
648 { return _M_t.key_comp(); }
649
650 /**
651 * Returns a value comparison object, built from the key comparison
652 * object out of which the %multimap was constructed.
653 */
654 value_compare
655 value_comp() const
656 { return value_compare(_M_t.key_comp()); }
657
658 // multimap operations
659 /**
660 * @brief Tries to locate an element in a %multimap.
661 * @param __x Key of (key, value) pair to be located.
662 * @return Iterator pointing to sought-after element,
663 * or end() if not found.
664 *
665 * This function takes a key and tries to locate the element with which
666 * the key matches. If successful the function returns an iterator
667 * pointing to the sought after %pair. If unsuccessful it returns the
668 * past-the-end ( @c end() ) iterator.
669 */
670 iterator
671 find(const key_type& __x)
672 { return _M_t.find(__x); }
673
674 /**
675 * @brief Tries to locate an element in a %multimap.
676 * @param __x Key of (key, value) pair to be located.
677 * @return Read-only (constant) iterator pointing to sought-after
678 * element, or end() if not found.
679 *
680 * This function takes a key and tries to locate the element with which
681 * the key matches. If successful the function returns a constant
682 * iterator pointing to the sought after %pair. If unsuccessful it
683 * returns the past-the-end ( @c end() ) iterator.
684 */
685 const_iterator
686 find(const key_type& __x) const
687 { return _M_t.find(__x); }
688
689 /**
690 * @brief Finds the number of elements with given key.
691 * @param __x Key of (key, value) pairs to be located.
692 * @return Number of elements with specified key.
693 */
694 size_type
695 count(const key_type& __x) const
696 { return _M_t.count(__x); }
697
698 /**
699 * @brief Finds the beginning of a subsequence matching given key.
700 * @param __x Key of (key, value) pair to be located.
701 * @return Iterator pointing to first element equal to or greater
702 * than key, or end().
703 *
704 * This function returns the first element of a subsequence of elements
705 * that matches the given key. If unsuccessful it returns an iterator
706 * pointing to the first element that has a greater value than given key
707 * or end() if no such element exists.
708 */
709 iterator
710 lower_bound(const key_type& __x)
711 { return _M_t.lower_bound(__x); }
712
713 /**
714 * @brief Finds the beginning of a subsequence matching given key.
715 * @param __x Key of (key, value) pair to be located.
716 * @return Read-only (constant) iterator pointing to first element
717 * equal to or greater than key, or end().
718 *
719 * This function returns the first element of a subsequence of
720 * elements that matches the given key. If unsuccessful the
721 * iterator will point to the next greatest element or, if no
722 * such greater element exists, to end().
723 */
724 const_iterator
725 lower_bound(const key_type& __x) const
726 { return _M_t.lower_bound(__x); }
727
728 /**
729 * @brief Finds the end of a subsequence matching given key.
730 * @param __x Key of (key, value) pair to be located.
731 * @return Iterator pointing to the first element
732 * greater than key, or end().
733 */
734 iterator
735 upper_bound(const key_type& __x)
736 { return _M_t.upper_bound(__x); }
737
738 /**
739 * @brief Finds the end of a subsequence matching given key.
740 * @param __x Key of (key, value) pair to be located.
741 * @return Read-only (constant) iterator pointing to first iterator
742 * greater than key, or end().
743 */
744 const_iterator
745 upper_bound(const key_type& __x) const
746 { return _M_t.upper_bound(__x); }
747
748 /**
749 * @brief Finds a subsequence matching given key.
750 * @param __x Key of (key, value) pairs to be located.
751 * @return Pair of iterators that possibly points to the subsequence
752 * matching given key.
753 *
754 * This function is equivalent to
755 * @code
756 * std::make_pair(c.lower_bound(val),
757 * c.upper_bound(val))
758 * @endcode
759 * (but is faster than making the calls separately).
760 */
761 std::pair<iterator, iterator>
762 equal_range(const key_type& __x)
763 { return _M_t.equal_range(__x); }
764
765 /**
766 * @brief Finds a subsequence matching given key.
767 * @param __x Key of (key, value) pairs to be located.
768 * @return Pair of read-only (constant) iterators that possibly points
769 * to the subsequence matching given key.
770 *
771 * This function is equivalent to
772 * @code
773 * std::make_pair(c.lower_bound(val),
774 * c.upper_bound(val))
775 * @endcode
776 * (but is faster than making the calls separately).
777 */
778 std::pair<const_iterator, const_iterator>
779 equal_range(const key_type& __x) const
780 { return _M_t.equal_range(__x); }
781
782 template<typename _K1, typename _T1, typename _C1, typename _A1>
783 friend bool
784 operator==(const multimap<_K1, _T1, _C1, _A1>&,
785 const multimap<_K1, _T1, _C1, _A1>&);
786
787 template<typename _K1, typename _T1, typename _C1, typename _A1>
788 friend bool
789 operator<(const multimap<_K1, _T1, _C1, _A1>&,
790 const multimap<_K1, _T1, _C1, _A1>&);
791 };
792
793 /**
794 * @brief Multimap equality comparison.
795 * @param __x A %multimap.
796 * @param __y A %multimap of the same type as @a __x.
797 * @return True iff the size and elements of the maps are equal.
798 *
799 * This is an equivalence relation. It is linear in the size of the
800 * multimaps. Multimaps are considered equivalent if their sizes are equal,
801 * and if corresponding elements compare equal.
802 */
803 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
804 inline bool
805 operator==(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
806 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
807 { return __x._M_t == __y._M_t; }
808
809 /**
810 * @brief Multimap ordering relation.
811 * @param __x A %multimap.
812 * @param __y A %multimap of the same type as @a __x.
813 * @return True iff @a x is lexicographically less than @a y.
814 *
815 * This is a total ordering relation. It is linear in the size of the
816 * multimaps. The elements must be comparable with @c <.
817 *
818 * See std::lexicographical_compare() for how the determination is made.
819 */
820 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
821 inline bool
822 operator<(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
823 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
824 { return __x._M_t < __y._M_t; }
825
826 /// Based on operator==
827 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
828 inline bool
829 operator!=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
830 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
831 { return !(__x == __y); }
832
833 /// Based on operator<
834 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
835 inline bool
836 operator>(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
837 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
838 { return __y < __x; }
839
840 /// Based on operator<
841 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
842 inline bool
843 operator<=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
844 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
845 { return !(__y < __x); }
846
847 /// Based on operator<
848 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
849 inline bool
850 operator>=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
851 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
852 { return !(__x < __y); }
853
854 /// See std::multimap::swap().
855 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
856 inline void
857 swap(multimap<_Key, _Tp, _Compare, _Alloc>& __x,
858 multimap<_Key, _Tp, _Compare, _Alloc>& __y)
859 { __x.swap(__y); }
860
861 _GLIBCXX_END_NAMESPACE_CONTAINER
862 } // namespace std
863
864 #endif /* _STL_MULTIMAP_H */
865