1// <bitset> -*- C++ -*-
2
3// Copyright (C) 2001-2018 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 * Copyright (c) 1998
27 * Silicon Graphics Computer Systems, Inc.
28 *
29 * Permission to use, copy, modify, distribute and sell this software
30 * and its documentation for any purpose is hereby granted without fee,
31 * provided that the above copyright notice appear in all copies and
32 * that both that copyright notice and this permission notice appear
33 * in supporting documentation.  Silicon Graphics makes no
34 * representations about the suitability of this software for any
35 * purpose.  It is provided "as is" without express or implied warranty.
36 */
37
38/** @file include/bitset
39 *  This is a Standard C++ Library header.
40 */
41
42#ifndef _GLIBCXX_BITSET
43#define _GLIBCXX_BITSET 1
44
45#pragma GCC system_header
46
47#include <string>
48#include <bits/functexcept.h>   // For invalid_argument, out_of_range,
49                                // overflow_error
50#include <iosfwd>
51#include <bits/cxxabi_forced.h>
52
53#if __cplusplus >= 201103L
54# include <bits/functional_hash.h>
55#endif
56
57#define _GLIBCXX_BITSET_BITS_PER_WORD  (__CHAR_BIT__ * __SIZEOF_LONG__)
58#define _GLIBCXX_BITSET_WORDS(__n) \
59  ((__n) / _GLIBCXX_BITSET_BITS_PER_WORD + \
60   ((__n) % _GLIBCXX_BITSET_BITS_PER_WORD == 0 ? 0 : 1))
61
62#define _GLIBCXX_BITSET_BITS_PER_ULL (__CHAR_BIT__ * __SIZEOF_LONG_LONG__)
63
64namespace std _GLIBCXX_VISIBILITY(default)
65{
66_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
67
68  /**
69   *  Base class, general case.  It is a class invariant that _Nw will be
70   *  nonnegative.
71   *
72   *  See documentation for bitset.
73  */
74  template<size_t _Nw>
75    struct _Base_bitset
76    {
77      typedef unsigned long _WordT;
78
79      /// 0 is the least significant word.
80      _WordT 		_M_w[_Nw];
81
82      _GLIBCXX_CONSTEXPR _Base_bitset() _GLIBCXX_NOEXCEPT
83      : _M_w() { }
84
85#if __cplusplus >= 201103L
86      constexpr _Base_bitset(unsigned long long __val) noexcept
87      : _M_w{ _WordT(__val)
88#if __SIZEOF_LONG_LONG__ > __SIZEOF_LONG__
89	       , _WordT(__val >> _GLIBCXX_BITSET_BITS_PER_WORD)
90#endif
91       } { }
92#else
93      _Base_bitset(unsigned long __val)
94      : _M_w()
95      { _M_w[0] = __val; }
96#endif
97
98      static _GLIBCXX_CONSTEXPR size_t
99      _S_whichword(size_t __pos) _GLIBCXX_NOEXCEPT
100      { return __pos / _GLIBCXX_BITSET_BITS_PER_WORD; }
101
102      static _GLIBCXX_CONSTEXPR size_t
103      _S_whichbyte(size_t __pos) _GLIBCXX_NOEXCEPT
104      { return (__pos % _GLIBCXX_BITSET_BITS_PER_WORD) / __CHAR_BIT__; }
105
106      static _GLIBCXX_CONSTEXPR size_t
107      _S_whichbit(size_t __pos) _GLIBCXX_NOEXCEPT
108      { return __pos % _GLIBCXX_BITSET_BITS_PER_WORD; }
109
110      static _GLIBCXX_CONSTEXPR _WordT
111      _S_maskbit(size_t __pos) _GLIBCXX_NOEXCEPT
112      { return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
113
114      _WordT&
115      _M_getword(size_t __pos) _GLIBCXX_NOEXCEPT
116      { return _M_w[_S_whichword(__pos)]; }
117
118      _GLIBCXX_CONSTEXPR _WordT
119      _M_getword(size_t __pos) const _GLIBCXX_NOEXCEPT
120      { return _M_w[_S_whichword(__pos)]; }
121
122#if __cplusplus >= 201103L
123      const _WordT*
124      _M_getdata() const noexcept
125      { return _M_w; }
126#endif
127
128      _WordT&
129      _M_hiword() _GLIBCXX_NOEXCEPT
130      { return _M_w[_Nw - 1]; }
131
132      _GLIBCXX_CONSTEXPR _WordT
133      _M_hiword() const _GLIBCXX_NOEXCEPT
134      { return _M_w[_Nw - 1]; }
135
136      void
137      _M_do_and(const _Base_bitset<_Nw>& __x) _GLIBCXX_NOEXCEPT
138      {
139	for (size_t __i = 0; __i < _Nw; __i++)
140	  _M_w[__i] &= __x._M_w[__i];
141      }
142
143      void
144      _M_do_or(const _Base_bitset<_Nw>& __x) _GLIBCXX_NOEXCEPT
145      {
146	for (size_t __i = 0; __i < _Nw; __i++)
147	  _M_w[__i] |= __x._M_w[__i];
148      }
149
150      void
151      _M_do_xor(const _Base_bitset<_Nw>& __x) _GLIBCXX_NOEXCEPT
152      {
153	for (size_t __i = 0; __i < _Nw; __i++)
154	  _M_w[__i] ^= __x._M_w[__i];
155      }
156
157      void
158      _M_do_left_shift(size_t __shift) _GLIBCXX_NOEXCEPT;
159
160      void
161      _M_do_right_shift(size_t __shift) _GLIBCXX_NOEXCEPT;
162
163      void
164      _M_do_flip() _GLIBCXX_NOEXCEPT
165      {
166	for (size_t __i = 0; __i < _Nw; __i++)
167	  _M_w[__i] = ~_M_w[__i];
168      }
169
170      void
171      _M_do_set() _GLIBCXX_NOEXCEPT
172      {
173	for (size_t __i = 0; __i < _Nw; __i++)
174	  _M_w[__i] = ~static_cast<_WordT>(0);
175      }
176
177      void
178      _M_do_reset() _GLIBCXX_NOEXCEPT
179      { __builtin_memset(_M_w, 0, _Nw * sizeof(_WordT)); }
180
181      bool
182      _M_is_equal(const _Base_bitset<_Nw>& __x) const _GLIBCXX_NOEXCEPT
183      {
184	for (size_t __i = 0; __i < _Nw; ++__i)
185	  if (_M_w[__i] != __x._M_w[__i])
186	    return false;
187	return true;
188      }
189
190      template<size_t _Nb>
191        bool
192        _M_are_all() const _GLIBCXX_NOEXCEPT
193        {
194	  for (size_t __i = 0; __i < _Nw - 1; __i++)
195	    if (_M_w[__i] != ~static_cast<_WordT>(0))
196	      return false;
197	  return _M_hiword() == (~static_cast<_WordT>(0)
198				 >> (_Nw * _GLIBCXX_BITSET_BITS_PER_WORD
199				     - _Nb));
200	}
201
202      bool
203      _M_is_any() const _GLIBCXX_NOEXCEPT
204      {
205	for (size_t __i = 0; __i < _Nw; __i++)
206	  if (_M_w[__i] != static_cast<_WordT>(0))
207	    return true;
208	return false;
209      }
210
211      size_t
212      _M_do_count() const _GLIBCXX_NOEXCEPT
213      {
214	size_t __result = 0;
215	for (size_t __i = 0; __i < _Nw; __i++)
216	  __result += __builtin_popcountl(_M_w[__i]);
217	return __result;
218      }
219
220      unsigned long
221      _M_do_to_ulong() const;
222
223#if __cplusplus >= 201103L
224      unsigned long long
225      _M_do_to_ullong() const;
226#endif
227
228      // find first "on" bit
229      size_t
230      _M_do_find_first(size_t) const _GLIBCXX_NOEXCEPT;
231
232      // find the next "on" bit that follows "prev"
233      size_t
234      _M_do_find_next(size_t, size_t) const _GLIBCXX_NOEXCEPT;
235    };
236
237  // Definitions of non-inline functions from _Base_bitset.
238  template<size_t _Nw>
239    void
240    _Base_bitset<_Nw>::_M_do_left_shift(size_t __shift) _GLIBCXX_NOEXCEPT
241    {
242      if (__builtin_expect(__shift != 0, 1))
243	{
244	  const size_t __wshift = __shift / _GLIBCXX_BITSET_BITS_PER_WORD;
245	  const size_t __offset = __shift % _GLIBCXX_BITSET_BITS_PER_WORD;
246
247	  if (__offset == 0)
248	    for (size_t __n = _Nw - 1; __n >= __wshift; --__n)
249	      _M_w[__n] = _M_w[__n - __wshift];
250	  else
251	    {
252	      const size_t __sub_offset = (_GLIBCXX_BITSET_BITS_PER_WORD
253					   - __offset);
254	      for (size_t __n = _Nw - 1; __n > __wshift; --__n)
255		_M_w[__n] = ((_M_w[__n - __wshift] << __offset)
256			     | (_M_w[__n - __wshift - 1] >> __sub_offset));
257	      _M_w[__wshift] = _M_w[0] << __offset;
258	    }
259
260	  std::fill(_M_w + 0, _M_w + __wshift, static_cast<_WordT>(0));
261	}
262    }
263
264  template<size_t _Nw>
265    void
266    _Base_bitset<_Nw>::_M_do_right_shift(size_t __shift) _GLIBCXX_NOEXCEPT
267    {
268      if (__builtin_expect(__shift != 0, 1))
269	{
270	  const size_t __wshift = __shift / _GLIBCXX_BITSET_BITS_PER_WORD;
271	  const size_t __offset = __shift % _GLIBCXX_BITSET_BITS_PER_WORD;
272	  const size_t __limit = _Nw - __wshift - 1;
273
274	  if (__offset == 0)
275	    for (size_t __n = 0; __n <= __limit; ++__n)
276	      _M_w[__n] = _M_w[__n + __wshift];
277	  else
278	    {
279	      const size_t __sub_offset = (_GLIBCXX_BITSET_BITS_PER_WORD
280					   - __offset);
281	      for (size_t __n = 0; __n < __limit; ++__n)
282		_M_w[__n] = ((_M_w[__n + __wshift] >> __offset)
283			     | (_M_w[__n + __wshift + 1] << __sub_offset));
284	      _M_w[__limit] = _M_w[_Nw-1] >> __offset;
285	    }
286
287	  std::fill(_M_w + __limit + 1, _M_w + _Nw, static_cast<_WordT>(0));
288	}
289    }
290
291  template<size_t _Nw>
292    unsigned long
293    _Base_bitset<_Nw>::_M_do_to_ulong() const
294    {
295      for (size_t __i = 1; __i < _Nw; ++__i)
296	if (_M_w[__i])
297	  __throw_overflow_error(__N("_Base_bitset::_M_do_to_ulong"));
298      return _M_w[0];
299    }
300
301#if __cplusplus >= 201103L
302  template<size_t _Nw>
303    unsigned long long
304    _Base_bitset<_Nw>::_M_do_to_ullong() const
305    {
306      const bool __dw = sizeof(unsigned long long) > sizeof(unsigned long);
307      for (size_t __i = 1 + __dw; __i < _Nw; ++__i)
308	if (_M_w[__i])
309	  __throw_overflow_error(__N("_Base_bitset::_M_do_to_ullong"));
310
311      if (__dw)
312	return _M_w[0] + (static_cast<unsigned long long>(_M_w[1])
313			  << _GLIBCXX_BITSET_BITS_PER_WORD);
314      return _M_w[0];
315    }
316#endif
317
318  template<size_t _Nw>
319    size_t
320    _Base_bitset<_Nw>::
321    _M_do_find_first(size_t __not_found) const _GLIBCXX_NOEXCEPT
322    {
323      for (size_t __i = 0; __i < _Nw; __i++)
324	{
325	  _WordT __thisword = _M_w[__i];
326	  if (__thisword != static_cast<_WordT>(0))
327	    return (__i * _GLIBCXX_BITSET_BITS_PER_WORD
328		    + __builtin_ctzl(__thisword));
329	}
330      // not found, so return an indication of failure.
331      return __not_found;
332    }
333
334  template<size_t _Nw>
335    size_t
336    _Base_bitset<_Nw>::
337    _M_do_find_next(size_t __prev, size_t __not_found) const _GLIBCXX_NOEXCEPT
338    {
339      // make bound inclusive
340      ++__prev;
341
342      // check out of bounds
343      if (__prev >= _Nw * _GLIBCXX_BITSET_BITS_PER_WORD)
344	return __not_found;
345
346      // search first word
347      size_t __i = _S_whichword(__prev);
348      _WordT __thisword = _M_w[__i];
349
350      // mask off bits below bound
351      __thisword &= (~static_cast<_WordT>(0)) << _S_whichbit(__prev);
352
353      if (__thisword != static_cast<_WordT>(0))
354	return (__i * _GLIBCXX_BITSET_BITS_PER_WORD
355		+ __builtin_ctzl(__thisword));
356
357      // check subsequent words
358      __i++;
359      for (; __i < _Nw; __i++)
360	{
361	  __thisword = _M_w[__i];
362	  if (__thisword != static_cast<_WordT>(0))
363	    return (__i * _GLIBCXX_BITSET_BITS_PER_WORD
364		    + __builtin_ctzl(__thisword));
365	}
366      // not found, so return an indication of failure.
367      return __not_found;
368    } // end _M_do_find_next
369
370  /**
371   *  Base class, specialization for a single word.
372   *
373   *  See documentation for bitset.
374  */
375  template<>
376    struct _Base_bitset<1>
377    {
378      typedef unsigned long _WordT;
379      _WordT _M_w;
380
381      _GLIBCXX_CONSTEXPR _Base_bitset() _GLIBCXX_NOEXCEPT
382      : _M_w(0)
383      { }
384
385#if __cplusplus >= 201103L
386      constexpr _Base_bitset(unsigned long long __val) noexcept
387#else
388      _Base_bitset(unsigned long __val)
389#endif
390      : _M_w(__val)
391      { }
392
393      static _GLIBCXX_CONSTEXPR size_t
394      _S_whichword(size_t __pos) _GLIBCXX_NOEXCEPT
395      { return __pos / _GLIBCXX_BITSET_BITS_PER_WORD; }
396
397      static _GLIBCXX_CONSTEXPR size_t
398      _S_whichbyte(size_t __pos) _GLIBCXX_NOEXCEPT
399      { return (__pos % _GLIBCXX_BITSET_BITS_PER_WORD) / __CHAR_BIT__; }
400
401      static _GLIBCXX_CONSTEXPR size_t
402      _S_whichbit(size_t __pos) _GLIBCXX_NOEXCEPT
403      {  return __pos % _GLIBCXX_BITSET_BITS_PER_WORD; }
404
405      static _GLIBCXX_CONSTEXPR _WordT
406      _S_maskbit(size_t __pos) _GLIBCXX_NOEXCEPT
407      { return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
408
409      _WordT&
410      _M_getword(size_t) _GLIBCXX_NOEXCEPT
411      { return _M_w; }
412
413      _GLIBCXX_CONSTEXPR _WordT
414      _M_getword(size_t) const _GLIBCXX_NOEXCEPT
415      { return _M_w; }
416
417#if __cplusplus >= 201103L
418      const _WordT*
419      _M_getdata() const noexcept
420      { return &_M_w; }
421#endif
422
423      _WordT&
424      _M_hiword() _GLIBCXX_NOEXCEPT
425      { return _M_w; }
426
427      _GLIBCXX_CONSTEXPR _WordT
428      _M_hiword() const _GLIBCXX_NOEXCEPT
429      { return _M_w; }
430
431      void
432      _M_do_and(const _Base_bitset<1>& __x) _GLIBCXX_NOEXCEPT
433      { _M_w &= __x._M_w; }
434
435      void
436      _M_do_or(const _Base_bitset<1>& __x) _GLIBCXX_NOEXCEPT
437      { _M_w |= __x._M_w; }
438
439      void
440      _M_do_xor(const _Base_bitset<1>& __x) _GLIBCXX_NOEXCEPT
441      { _M_w ^= __x._M_w; }
442
443      void
444      _M_do_left_shift(size_t __shift) _GLIBCXX_NOEXCEPT
445      { _M_w <<= __shift; }
446
447      void
448      _M_do_right_shift(size_t __shift) _GLIBCXX_NOEXCEPT
449      { _M_w >>= __shift; }
450
451      void
452      _M_do_flip() _GLIBCXX_NOEXCEPT
453      { _M_w = ~_M_w; }
454
455      void
456      _M_do_set() _GLIBCXX_NOEXCEPT
457      { _M_w = ~static_cast<_WordT>(0); }
458
459      void
460      _M_do_reset() _GLIBCXX_NOEXCEPT
461      { _M_w = 0; }
462
463      bool
464      _M_is_equal(const _Base_bitset<1>& __x) const _GLIBCXX_NOEXCEPT
465      { return _M_w == __x._M_w; }
466
467      template<size_t _Nb>
468        bool
469        _M_are_all() const _GLIBCXX_NOEXCEPT
470        { return _M_w == (~static_cast<_WordT>(0)
471			  >> (_GLIBCXX_BITSET_BITS_PER_WORD - _Nb)); }
472
473      bool
474      _M_is_any() const _GLIBCXX_NOEXCEPT
475      { return _M_w != 0; }
476
477      size_t
478      _M_do_count() const _GLIBCXX_NOEXCEPT
479      { return __builtin_popcountl(_M_w); }
480
481      unsigned long
482      _M_do_to_ulong() const _GLIBCXX_NOEXCEPT
483      { return _M_w; }
484
485#if __cplusplus >= 201103L
486      unsigned long long
487      _M_do_to_ullong() const noexcept
488      { return _M_w; }
489#endif
490
491      size_t
492      _M_do_find_first(size_t __not_found) const _GLIBCXX_NOEXCEPT
493      {
494        if (_M_w != 0)
495          return __builtin_ctzl(_M_w);
496        else
497          return __not_found;
498      }
499
500      // find the next "on" bit that follows "prev"
501      size_t
502      _M_do_find_next(size_t __prev, size_t __not_found) const
503	_GLIBCXX_NOEXCEPT
504      {
505	++__prev;
506	if (__prev >= ((size_t) _GLIBCXX_BITSET_BITS_PER_WORD))
507	  return __not_found;
508
509	_WordT __x = _M_w >> __prev;
510	if (__x != 0)
511	  return __builtin_ctzl(__x) + __prev;
512	else
513	  return __not_found;
514      }
515    };
516
517  /**
518   *  Base class, specialization for no storage (zero-length %bitset).
519   *
520   *  See documentation for bitset.
521  */
522  template<>
523    struct _Base_bitset<0>
524    {
525      typedef unsigned long _WordT;
526
527      _GLIBCXX_CONSTEXPR _Base_bitset() _GLIBCXX_NOEXCEPT
528      { }
529
530#if __cplusplus >= 201103L
531      constexpr _Base_bitset(unsigned long long) noexcept
532#else
533      _Base_bitset(unsigned long)
534#endif
535      { }
536
537      static _GLIBCXX_CONSTEXPR size_t
538      _S_whichword(size_t __pos) _GLIBCXX_NOEXCEPT
539      { return __pos / _GLIBCXX_BITSET_BITS_PER_WORD; }
540
541      static _GLIBCXX_CONSTEXPR size_t
542      _S_whichbyte(size_t __pos) _GLIBCXX_NOEXCEPT
543      { return (__pos % _GLIBCXX_BITSET_BITS_PER_WORD) / __CHAR_BIT__; }
544
545      static _GLIBCXX_CONSTEXPR size_t
546      _S_whichbit(size_t __pos) _GLIBCXX_NOEXCEPT
547      {  return __pos % _GLIBCXX_BITSET_BITS_PER_WORD; }
548
549      static _GLIBCXX_CONSTEXPR _WordT
550      _S_maskbit(size_t __pos) _GLIBCXX_NOEXCEPT
551      { return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
552
553      // This would normally give access to the data.  The bounds-checking
554      // in the bitset class will prevent the user from getting this far,
555      // but (1) it must still return an lvalue to compile, and (2) the
556      // user might call _Unchecked_set directly, in which case this /needs/
557      // to fail.  Let's not penalize zero-length users unless they actually
558      // make an unchecked call; all the memory ugliness is therefore
559      // localized to this single should-never-get-this-far function.
560      _WordT&
561      _M_getword(size_t) _GLIBCXX_NOEXCEPT
562      {
563	__throw_out_of_range(__N("_Base_bitset::_M_getword"));
564	return *new _WordT;
565      }
566
567      _GLIBCXX_CONSTEXPR _WordT
568      _M_getword(size_t) const _GLIBCXX_NOEXCEPT
569      { return 0; }
570
571      _GLIBCXX_CONSTEXPR _WordT
572      _M_hiword() const _GLIBCXX_NOEXCEPT
573      { return 0; }
574
575      void
576      _M_do_and(const _Base_bitset<0>&) _GLIBCXX_NOEXCEPT
577      { }
578
579      void
580      _M_do_or(const _Base_bitset<0>&) _GLIBCXX_NOEXCEPT
581      { }
582
583      void
584      _M_do_xor(const _Base_bitset<0>&) _GLIBCXX_NOEXCEPT
585      { }
586
587      void
588      _M_do_left_shift(size_t) _GLIBCXX_NOEXCEPT
589      { }
590
591      void
592      _M_do_right_shift(size_t) _GLIBCXX_NOEXCEPT
593      { }
594
595      void
596      _M_do_flip() _GLIBCXX_NOEXCEPT
597      { }
598
599      void
600      _M_do_set() _GLIBCXX_NOEXCEPT
601      { }
602
603      void
604      _M_do_reset() _GLIBCXX_NOEXCEPT
605      { }
606
607      // Are all empty bitsets equal to each other?  Are they equal to
608      // themselves?  How to compare a thing which has no state?  What is
609      // the sound of one zero-length bitset clapping?
610      bool
611      _M_is_equal(const _Base_bitset<0>&) const _GLIBCXX_NOEXCEPT
612      { return true; }
613
614      template<size_t _Nb>
615        bool
616        _M_are_all() const _GLIBCXX_NOEXCEPT
617        { return true; }
618
619      bool
620      _M_is_any() const _GLIBCXX_NOEXCEPT
621      { return false; }
622
623      size_t
624      _M_do_count() const _GLIBCXX_NOEXCEPT
625      { return 0; }
626
627      unsigned long
628      _M_do_to_ulong() const _GLIBCXX_NOEXCEPT
629      { return 0; }
630
631#if __cplusplus >= 201103L
632      unsigned long long
633      _M_do_to_ullong() const noexcept
634      { return 0; }
635#endif
636
637      // Normally "not found" is the size, but that could also be
638      // misinterpreted as an index in this corner case.  Oh well.
639      size_t
640      _M_do_find_first(size_t) const _GLIBCXX_NOEXCEPT
641      { return 0; }
642
643      size_t
644      _M_do_find_next(size_t, size_t) const _GLIBCXX_NOEXCEPT
645      { return 0; }
646    };
647
648
649  // Helper class to zero out the unused high-order bits in the highest word.
650  template<size_t _Extrabits>
651    struct _Sanitize
652    {
653      typedef unsigned long _WordT;
654
655      static void
656      _S_do_sanitize(_WordT& __val) _GLIBCXX_NOEXCEPT
657      { __val &= ~((~static_cast<_WordT>(0)) << _Extrabits); }
658    };
659
660  template<>
661    struct _Sanitize<0>
662    {
663      typedef unsigned long _WordT;
664
665      static void
666      _S_do_sanitize(_WordT) _GLIBCXX_NOEXCEPT { }
667    };
668
669#if __cplusplus >= 201103L
670  template<size_t _Nb, bool = (_Nb < _GLIBCXX_BITSET_BITS_PER_ULL)>
671    struct _Sanitize_val
672    {
673      static constexpr unsigned long long
674      _S_do_sanitize_val(unsigned long long __val)
675      { return __val; }
676    };
677
678  template<size_t _Nb>
679    struct _Sanitize_val<_Nb, true>
680    {
681      static constexpr unsigned long long
682      _S_do_sanitize_val(unsigned long long __val)
683      { return __val & ~((~static_cast<unsigned long long>(0)) << _Nb); }
684    };
685#endif
686
687  /**
688   *  @brief The %bitset class represents a @e fixed-size sequence of bits.
689   *  @ingroup utilities
690   *
691   *  (Note that %bitset does @e not meet the formal requirements of a
692   *  <a href="tables.html#65">container</a>.  Mainly, it lacks iterators.)
693   *
694   *  The template argument, @a Nb, may be any non-negative number,
695   *  specifying the number of bits (e.g., "0", "12", "1024*1024").
696   *
697   *  In the general unoptimized case, storage is allocated in word-sized
698   *  blocks.  Let B be the number of bits in a word, then (Nb+(B-1))/B
699   *  words will be used for storage.  B - Nb%B bits are unused.  (They are
700   *  the high-order bits in the highest word.)  It is a class invariant
701   *  that those unused bits are always zero.
702   *
703   *  If you think of %bitset as <em>a simple array of bits</em>, be
704   *  aware that your mental picture is reversed: a %bitset behaves
705   *  the same way as bits in integers do, with the bit at index 0 in
706   *  the <em>least significant / right-hand</em> position, and the bit at
707   *  index Nb-1 in the <em>most significant / left-hand</em> position.
708   *  Thus, unlike other containers, a %bitset's index <em>counts from
709   *  right to left</em>, to put it very loosely.
710   *
711   *  This behavior is preserved when translating to and from strings.  For
712   *  example, the first line of the following program probably prints
713   *  <em>b(&apos;a&apos;) is 0001100001</em> on a modern ASCII system.
714   *
715   *  @code
716   *     #include <bitset>
717   *     #include <iostream>
718   *     #include <sstream>
719   *
720   *     using namespace std;
721   *
722   *     int main()
723   *     {
724   *         long         a = 'a';
725   *         bitset<10>   b(a);
726   *
727   *         cout << "b('a') is " << b << endl;
728   *
729   *         ostringstream s;
730   *         s << b;
731   *         string  str = s.str();
732   *         cout << "index 3 in the string is " << str[3] << " but\n"
733   *              << "index 3 in the bitset is " << b[3] << endl;
734   *     }
735   *  @endcode
736   *
737   *  Also see:
738   *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/ext_containers.html
739   *  for a description of extensions.
740   *
741   *  Most of the actual code isn't contained in %bitset<> itself, but in the
742   *  base class _Base_bitset.  The base class works with whole words, not with
743   *  individual bits.  This allows us to specialize _Base_bitset for the
744   *  important special case where the %bitset is only a single word.
745   *
746   *  Extra confusion can result due to the fact that the storage for
747   *  _Base_bitset @e is a regular array, and is indexed as such.  This is
748   *  carefully encapsulated.
749  */
750  template<size_t _Nb>
751    class bitset
752    : private _Base_bitset<_GLIBCXX_BITSET_WORDS(_Nb)>
753    {
754    private:
755      typedef _Base_bitset<_GLIBCXX_BITSET_WORDS(_Nb)> _Base;
756      typedef unsigned long _WordT;
757
758      template<class _CharT, class _Traits, class _Alloc>
759      void
760      _M_check_initial_position(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
761				size_t __position) const
762      {
763	if (__position > __s.size())
764	  __throw_out_of_range_fmt(__N("bitset::bitset: __position "
765				       "(which is %zu) > __s.size() "
766				       "(which is %zu)"),
767				   __position, __s.size());
768      }
769
770      void _M_check(size_t __position, const char *__s) const
771      {
772	if (__position >= _Nb)
773	  __throw_out_of_range_fmt(__N("%s: __position (which is %zu) "
774				       ">= _Nb (which is %zu)"),
775				   __s, __position, _Nb);
776      }
777
778      void
779      _M_do_sanitize() _GLIBCXX_NOEXCEPT
780      {
781	typedef _Sanitize<_Nb % _GLIBCXX_BITSET_BITS_PER_WORD> __sanitize_type;
782	__sanitize_type::_S_do_sanitize(this->_M_hiword());
783      }
784
785#if __cplusplus >= 201103L
786      friend struct std::hash<bitset>;
787#endif
788
789    public:
790      /**
791       *  This encapsulates the concept of a single bit.  An instance of this
792       *  class is a proxy for an actual bit; this way the individual bit
793       *  operations are done as faster word-size bitwise instructions.
794       *
795       *  Most users will never need to use this class directly; conversions
796       *  to and from bool are automatic and should be transparent.  Overloaded
797       *  operators help to preserve the illusion.
798       *
799       *  (On a typical system, this <em>bit %reference</em> is 64
800       *  times the size of an actual bit.  Ha.)
801       */
802      class reference
803      {
804	friend class bitset;
805
806	_WordT*	_M_wp;
807	size_t 	_M_bpos;
808
809	// left undefined
810	reference();
811
812      public:
813	reference(bitset& __b, size_t __pos) _GLIBCXX_NOEXCEPT
814	{
815	  _M_wp = &__b._M_getword(__pos);
816	  _M_bpos = _Base::_S_whichbit(__pos);
817	}
818
819	~reference() _GLIBCXX_NOEXCEPT
820	{ }
821
822	// For b[i] = __x;
823	reference&
824	operator=(bool __x) _GLIBCXX_NOEXCEPT
825	{
826	  if (__x)
827	    *_M_wp |= _Base::_S_maskbit(_M_bpos);
828	  else
829	    *_M_wp &= ~_Base::_S_maskbit(_M_bpos);
830	  return *this;
831	}
832
833	// For b[i] = b[__j];
834	reference&
835	operator=(const reference& __j) _GLIBCXX_NOEXCEPT
836	{
837	  if ((*(__j._M_wp) & _Base::_S_maskbit(__j._M_bpos)))
838	    *_M_wp |= _Base::_S_maskbit(_M_bpos);
839	  else
840	    *_M_wp &= ~_Base::_S_maskbit(_M_bpos);
841	  return *this;
842	}
843
844	// Flips the bit
845	bool
846	operator~() const _GLIBCXX_NOEXCEPT
847	{ return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) == 0; }
848
849	// For __x = b[i];
850	operator bool() const _GLIBCXX_NOEXCEPT
851	{ return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) != 0; }
852
853	// For b[i].flip();
854	reference&
855	flip() _GLIBCXX_NOEXCEPT
856	{
857	  *_M_wp ^= _Base::_S_maskbit(_M_bpos);
858	  return *this;
859	}
860      };
861      friend class reference;
862
863      // 23.3.5.1 constructors:
864      /// All bits set to zero.
865      _GLIBCXX_CONSTEXPR bitset() _GLIBCXX_NOEXCEPT
866      { }
867
868      /// Initial bits bitwise-copied from a single word (others set to zero).
869#if __cplusplus >= 201103L
870      constexpr bitset(unsigned long long __val) noexcept
871      : _Base(_Sanitize_val<_Nb>::_S_do_sanitize_val(__val)) { }
872#else
873      bitset(unsigned long __val)
874      : _Base(__val)
875      { _M_do_sanitize(); }
876#endif
877
878      /**
879       *  Use a subset of a string.
880       *  @param  __s  A string of @a 0 and @a 1 characters.
881       *  @param  __position  Index of the first character in @a __s to use;
882       *                    defaults to zero.
883       *  @throw  std::out_of_range  If @a pos is bigger the size of @a __s.
884       *  @throw  std::invalid_argument  If a character appears in the string
885       *                                 which is neither @a 0 nor @a 1.
886       */
887      template<class _CharT, class _Traits, class _Alloc>
888	explicit
889	bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
890	       size_t __position = 0)
891	: _Base()
892	{
893	  _M_check_initial_position(__s, __position);
894	  _M_copy_from_string(__s, __position,
895			      std::basic_string<_CharT, _Traits, _Alloc>::npos,
896			      _CharT('0'), _CharT('1'));
897	}
898
899      /**
900       *  Use a subset of a string.
901       *  @param  __s  A string of @a 0 and @a 1 characters.
902       *  @param  __position  Index of the first character in @a __s to use.
903       *  @param  __n    The number of characters to copy.
904       *  @throw std::out_of_range If @a __position is bigger the size
905       *  of @a __s.
906       *  @throw  std::invalid_argument  If a character appears in the string
907       *                                 which is neither @a 0 nor @a 1.
908       */
909      template<class _CharT, class _Traits, class _Alloc>
910	bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
911	       size_t __position, size_t __n)
912	: _Base()
913	{
914	  _M_check_initial_position(__s, __position);
915	  _M_copy_from_string(__s, __position, __n, _CharT('0'), _CharT('1'));
916	}
917
918      // _GLIBCXX_RESOLVE_LIB_DEFECTS
919      // 396. what are characters zero and one.
920      template<class _CharT, class _Traits, class _Alloc>
921	bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
922	       size_t __position, size_t __n,
923	       _CharT __zero, _CharT __one = _CharT('1'))
924	: _Base()
925	{
926	  _M_check_initial_position(__s, __position);
927	  _M_copy_from_string(__s, __position, __n, __zero, __one);
928	}
929
930#if __cplusplus >= 201103L
931      /**
932       *  Construct from a character %array.
933       *  @param  __str  An %array of characters @a zero and @a one.
934       *  @param  __n    The number of characters to use.
935       *  @param  __zero The character corresponding to the value 0.
936       *  @param  __one  The character corresponding to the value 1.
937       *  @throw  std::invalid_argument If a character appears in the string
938       *                                which is neither @a __zero nor @a __one.
939       */
940      template<typename _CharT>
941        explicit
942        bitset(const _CharT* __str,
943	       typename std::basic_string<_CharT>::size_type __n
944	       = std::basic_string<_CharT>::npos,
945	       _CharT __zero = _CharT('0'), _CharT __one = _CharT('1'))
946        : _Base()
947        {
948	  if (!__str)
949	    __throw_logic_error(__N("bitset::bitset(const _CharT*, ...)"));
950
951	  if (__n == std::basic_string<_CharT>::npos)
952	    __n = std::char_traits<_CharT>::length(__str);
953	  _M_copy_from_ptr<_CharT, std::char_traits<_CharT>>(__str, __n, 0,
954							     __n, __zero,
955							     __one);
956	}
957#endif
958
959      // 23.3.5.2 bitset operations:
960      //@{
961      /**
962       *  Operations on bitsets.
963       *  @param  __rhs  A same-sized bitset.
964       *
965       *  These should be self-explanatory.
966       */
967      bitset<_Nb>&
968      operator&=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
969      {
970	this->_M_do_and(__rhs);
971	return *this;
972      }
973
974      bitset<_Nb>&
975      operator|=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
976      {
977	this->_M_do_or(__rhs);
978	return *this;
979      }
980
981      bitset<_Nb>&
982      operator^=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
983      {
984	this->_M_do_xor(__rhs);
985	return *this;
986      }
987      //@}
988
989      //@{
990      /**
991       *  Operations on bitsets.
992       *  @param  __position  The number of places to shift.
993       *
994       *  These should be self-explanatory.
995       */
996      bitset<_Nb>&
997      operator<<=(size_t __position) _GLIBCXX_NOEXCEPT
998      {
999	if (__builtin_expect(__position < _Nb, 1))
1000	  {
1001	    this->_M_do_left_shift(__position);
1002	    this->_M_do_sanitize();
1003	  }
1004	else
1005	  this->_M_do_reset();
1006	return *this;
1007      }
1008
1009      bitset<_Nb>&
1010      operator>>=(size_t __position) _GLIBCXX_NOEXCEPT
1011      {
1012	if (__builtin_expect(__position < _Nb, 1))
1013	  {
1014	    this->_M_do_right_shift(__position);
1015	    this->_M_do_sanitize();
1016	  }
1017	else
1018	  this->_M_do_reset();
1019	return *this;
1020      }
1021      //@}
1022
1023      //@{
1024      /**
1025       *  These versions of single-bit set, reset, flip, and test are
1026       *  extensions from the SGI version.  They do no range checking.
1027       *  @ingroup SGIextensions
1028       */
1029      bitset<_Nb>&
1030      _Unchecked_set(size_t __pos) _GLIBCXX_NOEXCEPT
1031      {
1032	this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
1033	return *this;
1034      }
1035
1036      bitset<_Nb>&
1037      _Unchecked_set(size_t __pos, int __val) _GLIBCXX_NOEXCEPT
1038      {
1039	if (__val)
1040	  this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
1041	else
1042	  this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
1043	return *this;
1044      }
1045
1046      bitset<_Nb>&
1047      _Unchecked_reset(size_t __pos) _GLIBCXX_NOEXCEPT
1048      {
1049	this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
1050	return *this;
1051      }
1052
1053      bitset<_Nb>&
1054      _Unchecked_flip(size_t __pos) _GLIBCXX_NOEXCEPT
1055      {
1056	this->_M_getword(__pos) ^= _Base::_S_maskbit(__pos);
1057	return *this;
1058      }
1059
1060      _GLIBCXX_CONSTEXPR bool
1061      _Unchecked_test(size_t __pos) const _GLIBCXX_NOEXCEPT
1062      { return ((this->_M_getword(__pos) & _Base::_S_maskbit(__pos))
1063		!= static_cast<_WordT>(0)); }
1064      //@}
1065
1066      // Set, reset, and flip.
1067      /**
1068       *  @brief Sets every bit to true.
1069       */
1070      bitset<_Nb>&
1071      set() _GLIBCXX_NOEXCEPT
1072      {
1073	this->_M_do_set();
1074	this->_M_do_sanitize();
1075	return *this;
1076      }
1077
1078      /**
1079       *  @brief Sets a given bit to a particular value.
1080       *  @param  __position  The index of the bit.
1081       *  @param  __val  Either true or false, defaults to true.
1082       *  @throw  std::out_of_range  If @a pos is bigger the size of the %set.
1083       */
1084      bitset<_Nb>&
1085      set(size_t __position, bool __val = true)
1086      {
1087	this->_M_check(__position, __N("bitset::set"));
1088	return _Unchecked_set(__position, __val);
1089      }
1090
1091      /**
1092       *  @brief Sets every bit to false.
1093       */
1094      bitset<_Nb>&
1095      reset() _GLIBCXX_NOEXCEPT
1096      {
1097	this->_M_do_reset();
1098	return *this;
1099      }
1100
1101      /**
1102       *  @brief Sets a given bit to false.
1103       *  @param  __position  The index of the bit.
1104       *  @throw  std::out_of_range  If @a pos is bigger the size of the %set.
1105       *
1106       *  Same as writing @c set(pos,false).
1107       */
1108      bitset<_Nb>&
1109      reset(size_t __position)
1110      {
1111	this->_M_check(__position, __N("bitset::reset"));
1112	return _Unchecked_reset(__position);
1113      }
1114
1115      /**
1116       *  @brief Toggles every bit to its opposite value.
1117       */
1118      bitset<_Nb>&
1119      flip() _GLIBCXX_NOEXCEPT
1120      {
1121	this->_M_do_flip();
1122	this->_M_do_sanitize();
1123	return *this;
1124      }
1125
1126      /**
1127       *  @brief Toggles a given bit to its opposite value.
1128       *  @param  __position  The index of the bit.
1129       *  @throw  std::out_of_range  If @a pos is bigger the size of the %set.
1130       */
1131      bitset<_Nb>&
1132      flip(size_t __position)
1133      {
1134	this->_M_check(__position, __N("bitset::flip"));
1135	return _Unchecked_flip(__position);
1136      }
1137
1138      /// See the no-argument flip().
1139      bitset<_Nb>
1140      operator~() const _GLIBCXX_NOEXCEPT
1141      { return bitset<_Nb>(*this).flip(); }
1142
1143      //@{
1144      /**
1145       *  @brief  Array-indexing support.
1146       *  @param  __position  Index into the %bitset.
1147       *  @return A bool for a <em>const %bitset</em>.  For non-const
1148       *           bitsets, an instance of the reference proxy class.
1149       *  @note  These operators do no range checking and throw no exceptions,
1150       *         as required by DR 11 to the standard.
1151       *
1152       *  _GLIBCXX_RESOLVE_LIB_DEFECTS Note that this implementation already
1153       *  resolves DR 11 (items 1 and 2), but does not do the range-checking
1154       *  required by that DR's resolution.  -pme
1155       *  The DR has since been changed:  range-checking is a precondition
1156       *  (users' responsibility), and these functions must not throw.  -pme
1157       */
1158      reference
1159      operator[](size_t __position)
1160      { return reference(*this, __position); }
1161
1162      _GLIBCXX_CONSTEXPR bool
1163      operator[](size_t __position) const
1164      { return _Unchecked_test(__position); }
1165      //@}
1166
1167      /**
1168       *  @brief Returns a numerical interpretation of the %bitset.
1169       *  @return  The integral equivalent of the bits.
1170       *  @throw  std::overflow_error  If there are too many bits to be
1171       *                               represented in an @c unsigned @c long.
1172       */
1173      unsigned long
1174      to_ulong() const
1175      { return this->_M_do_to_ulong(); }
1176
1177#if __cplusplus >= 201103L
1178      unsigned long long
1179      to_ullong() const
1180      { return this->_M_do_to_ullong(); }
1181#endif
1182
1183      /**
1184       *  @brief Returns a character interpretation of the %bitset.
1185       *  @return  The string equivalent of the bits.
1186       *
1187       *  Note the ordering of the bits:  decreasing character positions
1188       *  correspond to increasing bit positions (see the main class notes for
1189       *  an example).
1190       */
1191      template<class _CharT, class _Traits, class _Alloc>
1192	std::basic_string<_CharT, _Traits, _Alloc>
1193	to_string() const
1194	{
1195	  std::basic_string<_CharT, _Traits, _Alloc> __result;
1196	  _M_copy_to_string(__result, _CharT('0'), _CharT('1'));
1197	  return __result;
1198	}
1199
1200      // _GLIBCXX_RESOLVE_LIB_DEFECTS
1201      // 396. what are characters zero and one.
1202      template<class _CharT, class _Traits, class _Alloc>
1203	std::basic_string<_CharT, _Traits, _Alloc>
1204	to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1205	{
1206	  std::basic_string<_CharT, _Traits, _Alloc> __result;
1207	  _M_copy_to_string(__result, __zero, __one);
1208	  return __result;
1209	}
1210
1211      // _GLIBCXX_RESOLVE_LIB_DEFECTS
1212      // 434. bitset::to_string() hard to use.
1213      template<class _CharT, class _Traits>
1214	std::basic_string<_CharT, _Traits, std::allocator<_CharT> >
1215	to_string() const
1216	{ return to_string<_CharT, _Traits, std::allocator<_CharT> >(); }
1217
1218      // _GLIBCXX_RESOLVE_LIB_DEFECTS
1219      // 853. to_string needs updating with zero and one.
1220      template<class _CharT, class _Traits>
1221	std::basic_string<_CharT, _Traits, std::allocator<_CharT> >
1222	to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1223	{ return to_string<_CharT, _Traits,
1224	                   std::allocator<_CharT> >(__zero, __one); }
1225
1226      template<class _CharT>
1227	std::basic_string<_CharT, std::char_traits<_CharT>,
1228	                  std::allocator<_CharT> >
1229	to_string() const
1230	{
1231	  return to_string<_CharT, std::char_traits<_CharT>,
1232	                   std::allocator<_CharT> >();
1233	}
1234
1235      template<class _CharT>
1236	std::basic_string<_CharT, std::char_traits<_CharT>,
1237	                  std::allocator<_CharT> >
1238	to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1239	{
1240	  return to_string<_CharT, std::char_traits<_CharT>,
1241	                   std::allocator<_CharT> >(__zero, __one);
1242	}
1243
1244      std::basic_string<char, std::char_traits<char>, std::allocator<char> >
1245      to_string() const
1246      {
1247	return to_string<char, std::char_traits<char>,
1248	                 std::allocator<char> >();
1249      }
1250
1251      std::basic_string<char, std::char_traits<char>, std::allocator<char> >
1252      to_string(char __zero, char __one = '1') const
1253      {
1254	return to_string<char, std::char_traits<char>,
1255	                 std::allocator<char> >(__zero, __one);
1256      }
1257
1258      // Helper functions for string operations.
1259      template<class _CharT, class _Traits>
1260        void
1261        _M_copy_from_ptr(const _CharT*, size_t, size_t, size_t,
1262			 _CharT, _CharT);
1263
1264      template<class _CharT, class _Traits, class _Alloc>
1265	void
1266	_M_copy_from_string(const std::basic_string<_CharT,
1267			    _Traits, _Alloc>& __s, size_t __pos, size_t __n,
1268			    _CharT __zero, _CharT __one)
1269	{ _M_copy_from_ptr<_CharT, _Traits>(__s.data(), __s.size(), __pos, __n,
1270					    __zero, __one); }
1271
1272      template<class _CharT, class _Traits, class _Alloc>
1273	void
1274        _M_copy_to_string(std::basic_string<_CharT, _Traits, _Alloc>&,
1275			  _CharT, _CharT) const;
1276
1277      // NB: Backward compat.
1278      template<class _CharT, class _Traits, class _Alloc>
1279	void
1280	_M_copy_from_string(const std::basic_string<_CharT,
1281			    _Traits, _Alloc>& __s, size_t __pos, size_t __n)
1282	{ _M_copy_from_string(__s, __pos, __n, _CharT('0'), _CharT('1')); }
1283
1284      template<class _CharT, class _Traits, class _Alloc>
1285	void
1286        _M_copy_to_string(std::basic_string<_CharT, _Traits,_Alloc>& __s) const
1287	{ _M_copy_to_string(__s, _CharT('0'), _CharT('1')); }
1288
1289      /// Returns the number of bits which are set.
1290      size_t
1291      count() const _GLIBCXX_NOEXCEPT
1292      { return this->_M_do_count(); }
1293
1294      /// Returns the total number of bits.
1295      _GLIBCXX_CONSTEXPR size_t
1296      size() const _GLIBCXX_NOEXCEPT
1297      { return _Nb; }
1298
1299      //@{
1300      /// These comparisons for equality/inequality are, well, @e bitwise.
1301      bool
1302      operator==(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
1303      { return this->_M_is_equal(__rhs); }
1304
1305      bool
1306      operator!=(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
1307      { return !this->_M_is_equal(__rhs); }
1308      //@}
1309
1310      /**
1311       *  @brief Tests the value of a bit.
1312       *  @param  __position  The index of a bit.
1313       *  @return  The value at @a pos.
1314       *  @throw  std::out_of_range  If @a pos is bigger the size of the %set.
1315       */
1316      bool
1317      test(size_t __position) const
1318      {
1319	this->_M_check(__position, __N("bitset::test"));
1320	return _Unchecked_test(__position);
1321      }
1322
1323      // _GLIBCXX_RESOLVE_LIB_DEFECTS
1324      // DR 693. std::bitset::all() missing.
1325      /**
1326       *  @brief Tests whether all the bits are on.
1327       *  @return  True if all the bits are set.
1328       */
1329      bool
1330      all() const _GLIBCXX_NOEXCEPT
1331      { return this->template _M_are_all<_Nb>(); }
1332
1333      /**
1334       *  @brief Tests whether any of the bits are on.
1335       *  @return  True if at least one bit is set.
1336       */
1337      bool
1338      any() const _GLIBCXX_NOEXCEPT
1339      { return this->_M_is_any(); }
1340
1341      /**
1342       *  @brief Tests whether any of the bits are on.
1343       *  @return  True if none of the bits are set.
1344       */
1345      bool
1346      none() const _GLIBCXX_NOEXCEPT
1347      { return !this->_M_is_any(); }
1348
1349      //@{
1350      /// Self-explanatory.
1351      bitset<_Nb>
1352      operator<<(size_t __position) const _GLIBCXX_NOEXCEPT
1353      { return bitset<_Nb>(*this) <<= __position; }
1354
1355      bitset<_Nb>
1356      operator>>(size_t __position) const _GLIBCXX_NOEXCEPT
1357      { return bitset<_Nb>(*this) >>= __position; }
1358      //@}
1359
1360      /**
1361       *  @brief  Finds the index of the first "on" bit.
1362       *  @return  The index of the first bit set, or size() if not found.
1363       *  @ingroup SGIextensions
1364       *  @sa  _Find_next
1365       */
1366      size_t
1367      _Find_first() const _GLIBCXX_NOEXCEPT
1368      { return this->_M_do_find_first(_Nb); }
1369
1370      /**
1371       *  @brief  Finds the index of the next "on" bit after prev.
1372       *  @return  The index of the next bit set, or size() if not found.
1373       *  @param  __prev  Where to start searching.
1374       *  @ingroup SGIextensions
1375       *  @sa  _Find_first
1376       */
1377      size_t
1378      _Find_next(size_t __prev) const _GLIBCXX_NOEXCEPT
1379      { return this->_M_do_find_next(__prev, _Nb); }
1380    };
1381
1382  // Definitions of non-inline member functions.
1383  template<size_t _Nb>
1384    template<class _CharT, class _Traits>
1385      void
1386      bitset<_Nb>::
1387      _M_copy_from_ptr(const _CharT* __s, size_t __len,
1388		       size_t __pos, size_t __n, _CharT __zero, _CharT __one)
1389      {
1390	reset();
1391	const size_t __nbits = std::min(_Nb, std::min(__n, size_t(__len - __pos)));
1392	for (size_t __i = __nbits; __i > 0; --__i)
1393	  {
1394	    const _CharT __c = __s[__pos + __nbits - __i];
1395	    if (_Traits::eq(__c, __zero))
1396	      ;
1397	    else if (_Traits::eq(__c, __one))
1398	      _Unchecked_set(__i - 1);
1399	    else
1400	      __throw_invalid_argument(__N("bitset::_M_copy_from_ptr"));
1401	  }
1402      }
1403
1404  template<size_t _Nb>
1405    template<class _CharT, class _Traits, class _Alloc>
1406      void
1407      bitset<_Nb>::
1408      _M_copy_to_string(std::basic_string<_CharT, _Traits, _Alloc>& __s,
1409			_CharT __zero, _CharT __one) const
1410      {
1411	__s.assign(_Nb, __zero);
1412	for (size_t __i = _Nb; __i > 0; --__i)
1413	  if (_Unchecked_test(__i - 1))
1414	    _Traits::assign(__s[_Nb - __i], __one);
1415      }
1416
1417  // 23.3.5.3 bitset operations:
1418  //@{
1419  /**
1420   *  @brief  Global bitwise operations on bitsets.
1421   *  @param  __x  A bitset.
1422   *  @param  __y  A bitset of the same size as @a __x.
1423   *  @return  A new bitset.
1424   *
1425   *  These should be self-explanatory.
1426  */
1427  template<size_t _Nb>
1428    inline bitset<_Nb>
1429    operator&(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1430    {
1431      bitset<_Nb> __result(__x);
1432      __result &= __y;
1433      return __result;
1434    }
1435
1436  template<size_t _Nb>
1437    inline bitset<_Nb>
1438    operator|(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1439    {
1440      bitset<_Nb> __result(__x);
1441      __result |= __y;
1442      return __result;
1443    }
1444
1445  template <size_t _Nb>
1446    inline bitset<_Nb>
1447    operator^(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1448    {
1449      bitset<_Nb> __result(__x);
1450      __result ^= __y;
1451      return __result;
1452    }
1453  //@}
1454
1455  //@{
1456  /**
1457   *  @brief Global I/O operators for bitsets.
1458   *
1459   *  Direct I/O between streams and bitsets is supported.  Output is
1460   *  straightforward.  Input will skip whitespace, only accept @a 0 and @a 1
1461   *  characters, and will only extract as many digits as the %bitset will
1462   *  hold.
1463  */
1464  template<class _CharT, class _Traits, size_t _Nb>
1465    std::basic_istream<_CharT, _Traits>&
1466    operator>>(std::basic_istream<_CharT, _Traits>& __is, bitset<_Nb>& __x)
1467    {
1468      typedef typename _Traits::char_type          char_type;
1469      typedef std::basic_istream<_CharT, _Traits>  __istream_type;
1470      typedef typename __istream_type::ios_base    __ios_base;
1471
1472      std::basic_string<_CharT, _Traits> __tmp;
1473      __tmp.reserve(_Nb);
1474
1475      // _GLIBCXX_RESOLVE_LIB_DEFECTS
1476      // 303. Bitset input operator underspecified
1477      const char_type __zero = __is.widen('0');
1478      const char_type __one = __is.widen('1');
1479
1480      typename __ios_base::iostate __state = __ios_base::goodbit;
1481      typename __istream_type::sentry __sentry(__is);
1482      if (__sentry)
1483	{
1484	  __try
1485	    {
1486	      for (size_t __i = _Nb; __i > 0; --__i)
1487		{
1488		  static typename _Traits::int_type __eof = _Traits::eof();
1489
1490		  typename _Traits::int_type __c1 = __is.rdbuf()->sbumpc();
1491		  if (_Traits::eq_int_type(__c1, __eof))
1492		    {
1493		      __state |= __ios_base::eofbit;
1494		      break;
1495		    }
1496		  else
1497		    {
1498		      const char_type __c2 = _Traits::to_char_type(__c1);
1499		      if (_Traits::eq(__c2, __zero))
1500			__tmp.push_back(__zero);
1501		      else if (_Traits::eq(__c2, __one))
1502			__tmp.push_back(__one);
1503		      else if (_Traits::
1504			       eq_int_type(__is.rdbuf()->sputbackc(__c2),
1505					   __eof))
1506			{
1507			  __state |= __ios_base::failbit;
1508			  break;
1509			}
1510		    }
1511		}
1512	    }
1513	  __catch(__cxxabiv1::__forced_unwind&)
1514	    {
1515	      __is._M_setstate(__ios_base::badbit);
1516	      __throw_exception_again;
1517	    }
1518	  __catch(...)
1519	    { __is._M_setstate(__ios_base::badbit); }
1520	}
1521
1522      if (__tmp.empty() && _Nb)
1523	__state |= __ios_base::failbit;
1524      else
1525	__x._M_copy_from_string(__tmp, static_cast<size_t>(0), _Nb,
1526				__zero, __one);
1527      if (__state)
1528	__is.setstate(__state);
1529      return __is;
1530    }
1531
1532  template <class _CharT, class _Traits, size_t _Nb>
1533    std::basic_ostream<_CharT, _Traits>&
1534    operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1535	       const bitset<_Nb>& __x)
1536    {
1537      std::basic_string<_CharT, _Traits> __tmp;
1538
1539      // _GLIBCXX_RESOLVE_LIB_DEFECTS
1540      // 396. what are characters zero and one.
1541      const ctype<_CharT>& __ct = use_facet<ctype<_CharT> >(__os.getloc());
1542      __x._M_copy_to_string(__tmp, __ct.widen('0'), __ct.widen('1'));
1543      return __os << __tmp;
1544    }
1545  //@}
1546
1547_GLIBCXX_END_NAMESPACE_CONTAINER
1548} // namespace std
1549
1550#undef _GLIBCXX_BITSET_WORDS
1551#undef _GLIBCXX_BITSET_BITS_PER_WORD
1552#undef _GLIBCXX_BITSET_BITS_PER_ULL
1553
1554#if __cplusplus >= 201103L
1555
1556namespace std _GLIBCXX_VISIBILITY(default)
1557{
1558_GLIBCXX_BEGIN_NAMESPACE_VERSION
1559
1560  // DR 1182.
1561  /// std::hash specialization for bitset.
1562  template<size_t _Nb>
1563    struct hash<_GLIBCXX_STD_C::bitset<_Nb>>
1564    : public __hash_base<size_t, _GLIBCXX_STD_C::bitset<_Nb>>
1565    {
1566      size_t
1567      operator()(const _GLIBCXX_STD_C::bitset<_Nb>& __b) const noexcept
1568      {
1569	const size_t __clength = (_Nb + __CHAR_BIT__ - 1) / __CHAR_BIT__;
1570	return std::_Hash_impl::hash(__b._M_getdata(), __clength);
1571      }
1572    };
1573
1574  template<>
1575    struct hash<_GLIBCXX_STD_C::bitset<0>>
1576    : public __hash_base<size_t, _GLIBCXX_STD_C::bitset<0>>
1577    {
1578      size_t
1579      operator()(const _GLIBCXX_STD_C::bitset<0>&) const noexcept
1580      { return 0; }
1581    };
1582
1583_GLIBCXX_END_NAMESPACE_VERSION
1584} // namespace
1585
1586#endif // C++11
1587
1588#ifdef _GLIBCXX_DEBUG
1589# include <debug/bitset>
1590#endif
1591
1592#ifdef _GLIBCXX_PROFILE
1593# include <profile/bitset>
1594#endif
1595
1596#endif /* _GLIBCXX_BITSET */
1597