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