libstdc++
bitset
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1 // <bitset> -*- C++ -*-
2 
3 // Copyright (C) 2001-2023 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 <bits/functexcept.h> // For invalid_argument, out_of_range,
48  // overflow_error
49 #include <bits/stl_algobase.h> // For std::fill
50 
51 #if _GLIBCXX_HOSTED
52 # include <string>
53 # include <iosfwd>
54 # include <bits/cxxabi_forced.h>
55 #endif
56 
57 #if __cplusplus >= 201103L
58 # include <bits/functional_hash.h>
59 #endif
60 
61 #define _GLIBCXX_BITSET_BITS_PER_WORD (__CHAR_BIT__ * __SIZEOF_LONG__)
62 #define _GLIBCXX_BITSET_WORDS(__n) \
63  ((__n) / _GLIBCXX_BITSET_BITS_PER_WORD + \
64  ((__n) % _GLIBCXX_BITSET_BITS_PER_WORD == 0 ? 0 : 1))
65 
66 #define _GLIBCXX_BITSET_BITS_PER_ULL (__CHAR_BIT__ * __SIZEOF_LONG_LONG__)
67 
68 namespace std _GLIBCXX_VISIBILITY(default)
69 {
70 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
71 
72 #if __cplusplus > 202002L && _GLIBCXX_HOSTED
73 # define __cpp_lib_constexpr_bitset 202202L
74 #endif
75 
76  /**
77  * Base class, general case. It is a class invariant that _Nw will be
78  * nonnegative.
79  *
80  * See documentation for bitset.
81  */
82  template<size_t _Nw>
83  struct _Base_bitset
84  {
85  typedef unsigned long _WordT;
86 
87  /// 0 is the least significant word.
88  _WordT _M_w[_Nw];
89 
90  _GLIBCXX_CONSTEXPR _Base_bitset() _GLIBCXX_NOEXCEPT
91  : _M_w() { }
92 
93 #if __cplusplus >= 201103L
94  constexpr _Base_bitset(unsigned long long __val) noexcept
95  : _M_w{ _WordT(__val)
96 #if __SIZEOF_LONG_LONG__ > __SIZEOF_LONG__
97  , _WordT(__val >> _GLIBCXX_BITSET_BITS_PER_WORD)
98 #endif
99  } { }
100 #else
101  _Base_bitset(unsigned long __val)
102  : _M_w()
103  { _M_w[0] = __val; }
104 #endif
105 
106  static _GLIBCXX_CONSTEXPR size_t
107  _S_whichword(size_t __pos) _GLIBCXX_NOEXCEPT
108  { return __pos / _GLIBCXX_BITSET_BITS_PER_WORD; }
109 
110  static _GLIBCXX_CONSTEXPR size_t
111  _S_whichbyte(size_t __pos) _GLIBCXX_NOEXCEPT
112  { return (__pos % _GLIBCXX_BITSET_BITS_PER_WORD) / __CHAR_BIT__; }
113 
114  static _GLIBCXX_CONSTEXPR size_t
115  _S_whichbit(size_t __pos) _GLIBCXX_NOEXCEPT
116  { return __pos % _GLIBCXX_BITSET_BITS_PER_WORD; }
117 
118  static _GLIBCXX_CONSTEXPR _WordT
119  _S_maskbit(size_t __pos) _GLIBCXX_NOEXCEPT
120  { return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
121 
122  _GLIBCXX14_CONSTEXPR _WordT&
123  _M_getword(size_t __pos) _GLIBCXX_NOEXCEPT
124  { return _M_w[_S_whichword(__pos)]; }
125 
126  _GLIBCXX_CONSTEXPR _WordT
127  _M_getword(size_t __pos) const _GLIBCXX_NOEXCEPT
128  { return _M_w[_S_whichword(__pos)]; }
129 
130 #if __cplusplus >= 201103L
131  constexpr const _WordT*
132  _M_getdata() const noexcept
133  { return _M_w; }
134 #endif
135 
136  _GLIBCXX23_CONSTEXPR _WordT&
137  _M_hiword() _GLIBCXX_NOEXCEPT
138  { return _M_w[_Nw - 1]; }
139 
140  _GLIBCXX_CONSTEXPR _WordT
141  _M_hiword() const _GLIBCXX_NOEXCEPT
142  { return _M_w[_Nw - 1]; }
143 
144  _GLIBCXX23_CONSTEXPR void
145  _M_do_and(const _Base_bitset<_Nw>& __x) _GLIBCXX_NOEXCEPT
146  {
147  for (size_t __i = 0; __i < _Nw; __i++)
148  _M_w[__i] &= __x._M_w[__i];
149  }
150 
151  _GLIBCXX14_CONSTEXPR void
152  _M_do_or(const _Base_bitset<_Nw>& __x) _GLIBCXX_NOEXCEPT
153  {
154  for (size_t __i = 0; __i < _Nw; __i++)
155  _M_w[__i] |= __x._M_w[__i];
156  }
157 
158  _GLIBCXX14_CONSTEXPR void
159  _M_do_xor(const _Base_bitset<_Nw>& __x) _GLIBCXX_NOEXCEPT
160  {
161  for (size_t __i = 0; __i < _Nw; __i++)
162  _M_w[__i] ^= __x._M_w[__i];
163  }
164 
165  _GLIBCXX14_CONSTEXPR void
166  _M_do_left_shift(size_t __shift) _GLIBCXX_NOEXCEPT;
167 
168  _GLIBCXX14_CONSTEXPR void
169  _M_do_right_shift(size_t __shift) _GLIBCXX_NOEXCEPT;
170 
171  _GLIBCXX14_CONSTEXPR void
172  _M_do_flip() _GLIBCXX_NOEXCEPT
173  {
174  for (size_t __i = 0; __i < _Nw; __i++)
175  _M_w[__i] = ~_M_w[__i];
176  }
177 
178  _GLIBCXX14_CONSTEXPR void
179  _M_do_set() _GLIBCXX_NOEXCEPT
180  {
181  for (size_t __i = 0; __i < _Nw; __i++)
182  _M_w[__i] = ~static_cast<_WordT>(0);
183  }
184 
185  _GLIBCXX14_CONSTEXPR void
186  _M_do_reset() _GLIBCXX_NOEXCEPT
187  {
188 #if __cplusplus >= 201402L
189  if (__builtin_is_constant_evaluated())
190  {
191  for (_WordT& __w : _M_w)
192  __w = 0;
193  return;
194  }
195 #endif
196  __builtin_memset(_M_w, 0, _Nw * sizeof(_WordT));
197  }
198 
199  _GLIBCXX14_CONSTEXPR bool
200  _M_is_equal(const _Base_bitset<_Nw>& __x) const _GLIBCXX_NOEXCEPT
201  {
202  for (size_t __i = 0; __i < _Nw; ++__i)
203  if (_M_w[__i] != __x._M_w[__i])
204  return false;
205  return true;
206  }
207 
208  template<size_t _Nb>
209  _GLIBCXX14_CONSTEXPR bool
210  _M_are_all() const _GLIBCXX_NOEXCEPT
211  {
212  for (size_t __i = 0; __i < _Nw - 1; __i++)
213  if (_M_w[__i] != ~static_cast<_WordT>(0))
214  return false;
215  return _M_hiword() == (~static_cast<_WordT>(0)
216  >> (_Nw * _GLIBCXX_BITSET_BITS_PER_WORD
217  - _Nb));
218  }
219 
220  _GLIBCXX14_CONSTEXPR bool
221  _M_is_any() const _GLIBCXX_NOEXCEPT
222  {
223  for (size_t __i = 0; __i < _Nw; __i++)
224  if (_M_w[__i] != static_cast<_WordT>(0))
225  return true;
226  return false;
227  }
228 
229  _GLIBCXX14_CONSTEXPR size_t
230  _M_do_count() const _GLIBCXX_NOEXCEPT
231  {
232  size_t __result = 0;
233  for (size_t __i = 0; __i < _Nw; __i++)
234  __result += __builtin_popcountl(_M_w[__i]);
235  return __result;
236  }
237 
238  _GLIBCXX14_CONSTEXPR unsigned long
239  _M_do_to_ulong() const;
240 
241 #if __cplusplus >= 201103L
242  _GLIBCXX14_CONSTEXPR unsigned long long
243  _M_do_to_ullong() const;
244 #endif
245 
246  // find first "on" bit
247  _GLIBCXX14_CONSTEXPR size_t
248  _M_do_find_first(size_t) const _GLIBCXX_NOEXCEPT;
249 
250  // find the next "on" bit that follows "prev"
251  _GLIBCXX14_CONSTEXPR size_t
252  _M_do_find_next(size_t, size_t) const _GLIBCXX_NOEXCEPT;
253  };
254 
255  // Definitions of non-inline functions from _Base_bitset.
256  template<size_t _Nw>
257  _GLIBCXX14_CONSTEXPR void
258  _Base_bitset<_Nw>::_M_do_left_shift(size_t __shift) _GLIBCXX_NOEXCEPT
259  {
260  if (__builtin_expect(__shift != 0, 1))
261  {
262  const size_t __wshift = __shift / _GLIBCXX_BITSET_BITS_PER_WORD;
263  const size_t __offset = __shift % _GLIBCXX_BITSET_BITS_PER_WORD;
264 
265  if (__offset == 0)
266  for (size_t __n = _Nw - 1; __n >= __wshift; --__n)
267  _M_w[__n] = _M_w[__n - __wshift];
268  else
269  {
270  const size_t __sub_offset = (_GLIBCXX_BITSET_BITS_PER_WORD
271  - __offset);
272  for (size_t __n = _Nw - 1; __n > __wshift; --__n)
273  _M_w[__n] = ((_M_w[__n - __wshift] << __offset)
274  | (_M_w[__n - __wshift - 1] >> __sub_offset));
275  _M_w[__wshift] = _M_w[0] << __offset;
276  }
277 
278  std::fill(_M_w + 0, _M_w + __wshift, static_cast<_WordT>(0));
279  }
280  }
281 
282  template<size_t _Nw>
283  _GLIBCXX14_CONSTEXPR void
284  _Base_bitset<_Nw>::_M_do_right_shift(size_t __shift) _GLIBCXX_NOEXCEPT
285  {
286  if (__builtin_expect(__shift != 0, 1))
287  {
288  const size_t __wshift = __shift / _GLIBCXX_BITSET_BITS_PER_WORD;
289  const size_t __offset = __shift % _GLIBCXX_BITSET_BITS_PER_WORD;
290  const size_t __limit = _Nw - __wshift - 1;
291 
292  if (__offset == 0)
293  for (size_t __n = 0; __n <= __limit; ++__n)
294  _M_w[__n] = _M_w[__n + __wshift];
295  else
296  {
297  const size_t __sub_offset = (_GLIBCXX_BITSET_BITS_PER_WORD
298  - __offset);
299  for (size_t __n = 0; __n < __limit; ++__n)
300  _M_w[__n] = ((_M_w[__n + __wshift] >> __offset)
301  | (_M_w[__n + __wshift + 1] << __sub_offset));
302  _M_w[__limit] = _M_w[_Nw-1] >> __offset;
303  }
304 
305  std::fill(_M_w + __limit + 1, _M_w + _Nw, static_cast<_WordT>(0));
306  }
307  }
308 
309  template<size_t _Nw>
310  _GLIBCXX14_CONSTEXPR unsigned long
311  _Base_bitset<_Nw>::_M_do_to_ulong() const
312  {
313  for (size_t __i = 1; __i < _Nw; ++__i)
314  if (_M_w[__i])
315  __throw_overflow_error(__N("_Base_bitset::_M_do_to_ulong"));
316  return _M_w[0];
317  }
318 
319 #if __cplusplus >= 201103L
320  template<size_t _Nw>
321  _GLIBCXX14_CONSTEXPR unsigned long long
322  _Base_bitset<_Nw>::_M_do_to_ullong() const
323  {
324  const bool __dw = sizeof(unsigned long long) > sizeof(unsigned long);
325  for (size_t __i = 1 + __dw; __i < _Nw; ++__i)
326  if (_M_w[__i])
327  __throw_overflow_error(__N("_Base_bitset::_M_do_to_ullong"));
328 
329  if (__dw)
330  return _M_w[0] + (static_cast<unsigned long long>(_M_w[1])
331  << _GLIBCXX_BITSET_BITS_PER_WORD);
332  return _M_w[0];
333  }
334 #endif
335 
336  template<size_t _Nw>
337  _GLIBCXX14_CONSTEXPR size_t
338  _Base_bitset<_Nw>::
339  _M_do_find_first(size_t __not_found) const _GLIBCXX_NOEXCEPT
340  {
341  for (size_t __i = 0; __i < _Nw; __i++)
342  {
343  _WordT __thisword = _M_w[__i];
344  if (__thisword != static_cast<_WordT>(0))
345  return (__i * _GLIBCXX_BITSET_BITS_PER_WORD
346  + __builtin_ctzl(__thisword));
347  }
348  // not found, so return an indication of failure.
349  return __not_found;
350  }
351 
352  template<size_t _Nw>
353  _GLIBCXX14_CONSTEXPR size_t
354  _Base_bitset<_Nw>::
355  _M_do_find_next(size_t __prev, size_t __not_found) const _GLIBCXX_NOEXCEPT
356  {
357  // make bound inclusive
358  ++__prev;
359 
360  // check out of bounds
361  if (__prev >= _Nw * _GLIBCXX_BITSET_BITS_PER_WORD)
362  return __not_found;
363 
364  // search first word
365  size_t __i = _S_whichword(__prev);
366  _WordT __thisword = _M_w[__i];
367 
368  // mask off bits below bound
369  __thisword &= (~static_cast<_WordT>(0)) << _S_whichbit(__prev);
370 
371  if (__thisword != static_cast<_WordT>(0))
372  return (__i * _GLIBCXX_BITSET_BITS_PER_WORD
373  + __builtin_ctzl(__thisword));
374 
375  // check subsequent words
376  __i++;
377  for (; __i < _Nw; __i++)
378  {
379  __thisword = _M_w[__i];
380  if (__thisword != static_cast<_WordT>(0))
381  return (__i * _GLIBCXX_BITSET_BITS_PER_WORD
382  + __builtin_ctzl(__thisword));
383  }
384  // not found, so return an indication of failure.
385  return __not_found;
386  } // end _M_do_find_next
387 
388  /**
389  * Base class, specialization for a single word.
390  *
391  * See documentation for bitset.
392  */
393  template<>
394  struct _Base_bitset<1>
395  {
396  typedef unsigned long _WordT;
397  _WordT _M_w;
398 
399  _GLIBCXX_CONSTEXPR _Base_bitset() _GLIBCXX_NOEXCEPT
400  : _M_w(0)
401  { }
402 
403 #if __cplusplus >= 201103L
404  constexpr _Base_bitset(unsigned long long __val) noexcept
405 #else
406  _Base_bitset(unsigned long __val)
407 #endif
408  : _M_w(__val)
409  { }
410 
411  static _GLIBCXX_CONSTEXPR size_t
412  _S_whichword(size_t __pos) _GLIBCXX_NOEXCEPT
413  { return __pos / _GLIBCXX_BITSET_BITS_PER_WORD; }
414 
415  static _GLIBCXX_CONSTEXPR size_t
416  _S_whichbyte(size_t __pos) _GLIBCXX_NOEXCEPT
417  { return (__pos % _GLIBCXX_BITSET_BITS_PER_WORD) / __CHAR_BIT__; }
418 
419  static _GLIBCXX_CONSTEXPR size_t
420  _S_whichbit(size_t __pos) _GLIBCXX_NOEXCEPT
421  { return __pos % _GLIBCXX_BITSET_BITS_PER_WORD; }
422 
423  static _GLIBCXX_CONSTEXPR _WordT
424  _S_maskbit(size_t __pos) _GLIBCXX_NOEXCEPT
425  { return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
426 
427  _GLIBCXX14_CONSTEXPR _WordT&
428  _M_getword(size_t) _GLIBCXX_NOEXCEPT
429  { return _M_w; }
430 
431  _GLIBCXX_CONSTEXPR _WordT
432  _M_getword(size_t) const _GLIBCXX_NOEXCEPT
433  { return _M_w; }
434 
435 #if __cplusplus >= 201103L
436  constexpr const _WordT*
437  _M_getdata() const noexcept
438  { return &_M_w; }
439 #endif
440 
441  _GLIBCXX14_CONSTEXPR _WordT&
442  _M_hiword() _GLIBCXX_NOEXCEPT
443  { return _M_w; }
444 
445  _GLIBCXX_CONSTEXPR _WordT
446  _M_hiword() const _GLIBCXX_NOEXCEPT
447  { return _M_w; }
448 
449  _GLIBCXX14_CONSTEXPR void
450  _M_do_and(const _Base_bitset<1>& __x) _GLIBCXX_NOEXCEPT
451  { _M_w &= __x._M_w; }
452 
453  _GLIBCXX14_CONSTEXPR void
454  _M_do_or(const _Base_bitset<1>& __x) _GLIBCXX_NOEXCEPT
455  { _M_w |= __x._M_w; }
456 
457  _GLIBCXX14_CONSTEXPR void
458  _M_do_xor(const _Base_bitset<1>& __x) _GLIBCXX_NOEXCEPT
459  { _M_w ^= __x._M_w; }
460 
461  _GLIBCXX14_CONSTEXPR void
462  _M_do_left_shift(size_t __shift) _GLIBCXX_NOEXCEPT
463  { _M_w <<= __shift; }
464 
465  _GLIBCXX14_CONSTEXPR void
466  _M_do_right_shift(size_t __shift) _GLIBCXX_NOEXCEPT
467  { _M_w >>= __shift; }
468 
469  _GLIBCXX14_CONSTEXPR void
470  _M_do_flip() _GLIBCXX_NOEXCEPT
471  { _M_w = ~_M_w; }
472 
473  _GLIBCXX14_CONSTEXPR void
474  _M_do_set() _GLIBCXX_NOEXCEPT
475  { _M_w = ~static_cast<_WordT>(0); }
476 
477  _GLIBCXX14_CONSTEXPR void
478  _M_do_reset() _GLIBCXX_NOEXCEPT
479  { _M_w = 0; }
480 
481  _GLIBCXX14_CONSTEXPR bool
482  _M_is_equal(const _Base_bitset<1>& __x) const _GLIBCXX_NOEXCEPT
483  { return _M_w == __x._M_w; }
484 
485  template<size_t _Nb>
486  _GLIBCXX14_CONSTEXPR bool
487  _M_are_all() const _GLIBCXX_NOEXCEPT
488  { return _M_w == (~static_cast<_WordT>(0)
489  >> (_GLIBCXX_BITSET_BITS_PER_WORD - _Nb)); }
490 
491  _GLIBCXX14_CONSTEXPR bool
492  _M_is_any() const _GLIBCXX_NOEXCEPT
493  { return _M_w != 0; }
494 
495  _GLIBCXX14_CONSTEXPR size_t
496  _M_do_count() const _GLIBCXX_NOEXCEPT
497  { return __builtin_popcountl(_M_w); }
498 
499  _GLIBCXX14_CONSTEXPR unsigned long
500  _M_do_to_ulong() const _GLIBCXX_NOEXCEPT
501  { return _M_w; }
502 
503 #if __cplusplus >= 201103L
504  constexpr unsigned long long
505  _M_do_to_ullong() const noexcept
506  { return _M_w; }
507 #endif
508 
509  _GLIBCXX14_CONSTEXPR size_t
510  _M_do_find_first(size_t __not_found) const _GLIBCXX_NOEXCEPT
511  {
512  if (_M_w != 0)
513  return __builtin_ctzl(_M_w);
514  else
515  return __not_found;
516  }
517 
518  // find the next "on" bit that follows "prev"
519  _GLIBCXX14_CONSTEXPR size_t
520  _M_do_find_next(size_t __prev, size_t __not_found) const
521  _GLIBCXX_NOEXCEPT
522  {
523  ++__prev;
524  if (__prev >= ((size_t) _GLIBCXX_BITSET_BITS_PER_WORD))
525  return __not_found;
526 
527  _WordT __x = _M_w >> __prev;
528  if (__x != 0)
529  return __builtin_ctzl(__x) + __prev;
530  else
531  return __not_found;
532  }
533  };
534 
535  /**
536  * Base class, specialization for no storage (zero-length %bitset).
537  *
538  * See documentation for bitset.
539  */
540  template<>
541  struct _Base_bitset<0>
542  {
543  typedef unsigned long _WordT;
544 
545  _GLIBCXX_CONSTEXPR _Base_bitset() _GLIBCXX_NOEXCEPT
546  { }
547 
548 #if __cplusplus >= 201103L
549  constexpr _Base_bitset(unsigned long long) noexcept
550 #else
551  _Base_bitset(unsigned long)
552 #endif
553  { }
554 
555  static _GLIBCXX_CONSTEXPR size_t
556  _S_whichword(size_t __pos) _GLIBCXX_NOEXCEPT
557  { return __pos / _GLIBCXX_BITSET_BITS_PER_WORD; }
558 
559  static _GLIBCXX_CONSTEXPR size_t
560  _S_whichbyte(size_t __pos) _GLIBCXX_NOEXCEPT
561  { return (__pos % _GLIBCXX_BITSET_BITS_PER_WORD) / __CHAR_BIT__; }
562 
563  static _GLIBCXX_CONSTEXPR size_t
564  _S_whichbit(size_t __pos) _GLIBCXX_NOEXCEPT
565  { return __pos % _GLIBCXX_BITSET_BITS_PER_WORD; }
566 
567  static _GLIBCXX_CONSTEXPR _WordT
568  _S_maskbit(size_t __pos) _GLIBCXX_NOEXCEPT
569  { return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
570 
571  // This would normally give access to the data. The bounds-checking
572  // in the bitset class will prevent the user from getting this far,
573  // but this must fail if the user calls _Unchecked_set directly.
574  // Let's not penalize zero-length users unless they actually
575  // make an unchecked call; all the memory ugliness is therefore
576  // localized to this single should-never-get-this-far function.
577  __attribute__((__noreturn__))
578  _WordT&
579  _M_getword(size_t) _GLIBCXX_NOEXCEPT
580  { __throw_out_of_range(__N("_Base_bitset::_M_getword")); }
581 
582  _GLIBCXX_CONSTEXPR _WordT
583  _M_getword(size_t) const _GLIBCXX_NOEXCEPT
584  { return 0; }
585 
586  _GLIBCXX_CONSTEXPR _WordT
587  _M_hiword() const _GLIBCXX_NOEXCEPT
588  { return 0; }
589 
590  _GLIBCXX14_CONSTEXPR void
591  _M_do_and(const _Base_bitset<0>&) _GLIBCXX_NOEXCEPT
592  { }
593 
594  _GLIBCXX14_CONSTEXPR void
595  _M_do_or(const _Base_bitset<0>&) _GLIBCXX_NOEXCEPT
596  { }
597 
598  _GLIBCXX14_CONSTEXPR void
599  _M_do_xor(const _Base_bitset<0>&) _GLIBCXX_NOEXCEPT
600  { }
601 
602  _GLIBCXX14_CONSTEXPR void
603  _M_do_left_shift(size_t) _GLIBCXX_NOEXCEPT
604  { }
605 
606  _GLIBCXX14_CONSTEXPR void
607  _M_do_right_shift(size_t) _GLIBCXX_NOEXCEPT
608  { }
609 
610  _GLIBCXX14_CONSTEXPR void
611  _M_do_flip() _GLIBCXX_NOEXCEPT
612  { }
613 
614  _GLIBCXX14_CONSTEXPR void
615  _M_do_set() _GLIBCXX_NOEXCEPT
616  { }
617 
618  _GLIBCXX14_CONSTEXPR void
619  _M_do_reset() _GLIBCXX_NOEXCEPT
620  { }
621 
622  // Are all empty bitsets equal to each other? Are they equal to
623  // themselves? How to compare a thing which has no state? What is
624  // the sound of one zero-length bitset clapping?
625  _GLIBCXX_CONSTEXPR bool
626  _M_is_equal(const _Base_bitset<0>&) const _GLIBCXX_NOEXCEPT
627  { return true; }
628 
629  template<size_t _Nb>
630  _GLIBCXX_CONSTEXPR bool
631  _M_are_all() const _GLIBCXX_NOEXCEPT
632  { return true; }
633 
634  _GLIBCXX_CONSTEXPR bool
635  _M_is_any() const _GLIBCXX_NOEXCEPT
636  { return false; }
637 
638  _GLIBCXX_CONSTEXPR size_t
639  _M_do_count() const _GLIBCXX_NOEXCEPT
640  { return 0; }
641 
642  _GLIBCXX_CONSTEXPR unsigned long
643  _M_do_to_ulong() const _GLIBCXX_NOEXCEPT
644  { return 0; }
645 
646 #if __cplusplus >= 201103L
647  constexpr unsigned long long
648  _M_do_to_ullong() const noexcept
649  { return 0; }
650 #endif
651 
652  // Normally "not found" is the size, but that could also be
653  // misinterpreted as an index in this corner case. Oh well.
654  _GLIBCXX_CONSTEXPR size_t
655  _M_do_find_first(size_t) const _GLIBCXX_NOEXCEPT
656  { return 0; }
657 
658  _GLIBCXX_CONSTEXPR size_t
659  _M_do_find_next(size_t, size_t) const _GLIBCXX_NOEXCEPT
660  { return 0; }
661  };
662 
663 
664  // Helper class to zero out the unused high-order bits in the highest word.
665  template<size_t _Extrabits>
666  struct _Sanitize
667  {
668  typedef unsigned long _WordT;
669 
670  static _GLIBCXX14_CONSTEXPR void
671  _S_do_sanitize(_WordT& __val) _GLIBCXX_NOEXCEPT
672  { __val &= ~((~static_cast<_WordT>(0)) << _Extrabits); }
673  };
674 
675  template<>
676  struct _Sanitize<0>
677  {
678  typedef unsigned long _WordT;
679 
680  static _GLIBCXX14_CONSTEXPR void
681  _S_do_sanitize(_WordT) _GLIBCXX_NOEXCEPT { }
682  };
683 
684 #if __cplusplus >= 201103L
685  template<size_t _Nb, bool = (_Nb < _GLIBCXX_BITSET_BITS_PER_ULL)>
686  struct _Sanitize_val
687  {
688  static constexpr unsigned long long
689  _S_do_sanitize_val(unsigned long long __val)
690  { return __val; }
691  };
692 
693  template<size_t _Nb>
694  struct _Sanitize_val<_Nb, true>
695  {
696  static constexpr unsigned long long
697  _S_do_sanitize_val(unsigned long long __val)
698  { return __val & ~((~static_cast<unsigned long long>(0)) << _Nb); }
699  };
700 
701  namespace __bitset
702  {
703 #if _GLIBCXX_HOSTED
704  template<typename _CharT>
705  using __string = std::basic_string<_CharT>;
706 #else
707  template<typename _CharT>
708  struct __string
709  {
710  using size_type = size_t;
711  static constexpr size_type npos = size_type(-1);
712 
713  struct traits_type
714  {
715  static _GLIBCXX14_CONSTEXPR size_t
716  length(const _CharT* __s) noexcept
717  {
718  size_t __n = 0;
719  while (__s[__n])
720  __n++;
721  return __n;
722  }
723 
724  static constexpr bool
725  eq(_CharT __l, _CharT __r) noexcept
726  { return __l == __r; }
727  };
728  };
729 #endif // HOSTED
730  } // namespace __bitset
731 #endif // C++11
732 
733  /**
734  * @brief The %bitset class represents a @e fixed-size sequence of bits.
735  * @ingroup utilities
736  *
737  * (Note that %bitset does @e not meet the formal requirements of a
738  * <a href="tables.html#65">container</a>. Mainly, it lacks iterators.)
739  *
740  * The template argument, @a Nb, may be any non-negative number,
741  * specifying the number of bits (e.g., "0", "12", "1024*1024").
742  *
743  * In the general unoptimized case, storage is allocated in word-sized
744  * blocks. Let B be the number of bits in a word, then (Nb+(B-1))/B
745  * words will be used for storage. B - Nb%B bits are unused. (They are
746  * the high-order bits in the highest word.) It is a class invariant
747  * that those unused bits are always zero.
748  *
749  * If you think of %bitset as <em>a simple array of bits</em>, be
750  * aware that your mental picture is reversed: a %bitset behaves
751  * the same way as bits in integers do, with the bit at index 0 in
752  * the <em>least significant / right-hand</em> position, and the bit at
753  * index Nb-1 in the <em>most significant / left-hand</em> position.
754  * Thus, unlike other containers, a %bitset's index <em>counts from
755  * right to left</em>, to put it very loosely.
756  *
757  * This behavior is preserved when translating to and from strings. For
758  * example, the first line of the following program probably prints
759  * <em>b(&apos;a&apos;) is 0001100001</em> on a modern ASCII system.
760  *
761  * @code
762  * #include <bitset>
763  * #include <iostream>
764  * #include <sstream>
765  *
766  * using namespace std;
767  *
768  * int main()
769  * {
770  * long a = 'a';
771  * bitset<10> b(a);
772  *
773  * cout << "b('a') is " << b << endl;
774  *
775  * ostringstream s;
776  * s << b;
777  * string str = s.str();
778  * cout << "index 3 in the string is " << str[3] << " but\n"
779  * << "index 3 in the bitset is " << b[3] << endl;
780  * }
781  * @endcode
782  *
783  * Also see:
784  * https://gcc.gnu.org/onlinedocs/libstdc++/manual/ext_containers.html
785  * for a description of extensions.
786  *
787  * Most of the actual code isn't contained in %bitset<> itself, but in the
788  * base class _Base_bitset. The base class works with whole words, not with
789  * individual bits. This allows us to specialize _Base_bitset for the
790  * important special case where the %bitset is only a single word.
791  *
792  * Extra confusion can result due to the fact that the storage for
793  * _Base_bitset @e is a regular array, and is indexed as such. This is
794  * carefully encapsulated.
795  */
796  template<size_t _Nb>
797  class bitset
798  : private _Base_bitset<_GLIBCXX_BITSET_WORDS(_Nb)>
799  {
800  private:
801  typedef _Base_bitset<_GLIBCXX_BITSET_WORDS(_Nb)> _Base;
802  typedef unsigned long _WordT;
803 
804 #if _GLIBCXX_HOSTED
805  template<class _CharT, class _Traits, class _Alloc>
806  _GLIBCXX23_CONSTEXPR
807  void
808  _M_check_initial_position(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
809  size_t __position) const
810  {
811  if (__position > __s.size())
812  __throw_out_of_range_fmt(__N("bitset::bitset: __position "
813  "(which is %zu) > __s.size() "
814  "(which is %zu)"),
815  __position, __s.size());
816  }
817 #endif // HOSTED
818 
819  _GLIBCXX23_CONSTEXPR
820  void _M_check(size_t __position, const char *__s) const
821  {
822  if (__position >= _Nb)
823  __throw_out_of_range_fmt(__N("%s: __position (which is %zu) "
824  ">= _Nb (which is %zu)"),
825  __s, __position, _Nb);
826  }
827 
828  _GLIBCXX23_CONSTEXPR
829  void
830  _M_do_sanitize() _GLIBCXX_NOEXCEPT
831  {
832  typedef _Sanitize<_Nb % _GLIBCXX_BITSET_BITS_PER_WORD> __sanitize_type;
833  __sanitize_type::_S_do_sanitize(this->_M_hiword());
834  }
835 
836 #if __cplusplus >= 201103L
837  friend struct std::hash<bitset>;
838 #endif
839 
840  public:
841  /**
842  * This encapsulates the concept of a single bit. An instance of this
843  * class is a proxy for an actual bit; this way the individual bit
844  * operations are done as faster word-size bitwise instructions.
845  *
846  * Most users will never need to use this class directly; conversions
847  * to and from bool are automatic and should be transparent. Overloaded
848  * operators help to preserve the illusion.
849  *
850  * (On a typical system, this <em>bit %reference</em> is 64
851  * times the size of an actual bit. Ha.)
852  */
853  class reference
854  {
855  friend class bitset;
856 
857  _WordT* _M_wp;
858  size_t _M_bpos;
859 
860  // left undefined
861  reference();
862 
863  public:
864  _GLIBCXX23_CONSTEXPR
865  reference(bitset& __b, size_t __pos) _GLIBCXX_NOEXCEPT
866  {
867  _M_wp = &__b._M_getword(__pos);
868  _M_bpos = _Base::_S_whichbit(__pos);
869  }
870 
871 #if __cplusplus >= 201103L
872  reference(const reference&) = default;
873 #endif
874 
875 #if __cplusplus > 202002L && __cpp_constexpr_dynamic_alloc
876  constexpr
877 #endif
878  ~reference() _GLIBCXX_NOEXCEPT
879  { }
880 
881  // For b[i] = __x;
882  _GLIBCXX23_CONSTEXPR
883  reference&
884  operator=(bool __x) _GLIBCXX_NOEXCEPT
885  {
886  if (__x)
887  *_M_wp |= _Base::_S_maskbit(_M_bpos);
888  else
889  *_M_wp &= ~_Base::_S_maskbit(_M_bpos);
890  return *this;
891  }
892 
893  // For b[i] = b[__j];
894  _GLIBCXX23_CONSTEXPR
895  reference&
896  operator=(const reference& __j) _GLIBCXX_NOEXCEPT
897  {
898  if ((*(__j._M_wp) & _Base::_S_maskbit(__j._M_bpos)))
899  *_M_wp |= _Base::_S_maskbit(_M_bpos);
900  else
901  *_M_wp &= ~_Base::_S_maskbit(_M_bpos);
902  return *this;
903  }
904 
905  // Flips the bit
906  _GLIBCXX23_CONSTEXPR
907  bool
908  operator~() const _GLIBCXX_NOEXCEPT
909  { return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) == 0; }
910 
911  // For __x = b[i];
912  _GLIBCXX23_CONSTEXPR
913  operator bool() const _GLIBCXX_NOEXCEPT
914  { return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) != 0; }
915 
916  // For b[i].flip();
917  _GLIBCXX23_CONSTEXPR
918  reference&
919  flip() _GLIBCXX_NOEXCEPT
920  {
921  *_M_wp ^= _Base::_S_maskbit(_M_bpos);
922  return *this;
923  }
924  };
925  friend class reference;
926 
927  // 23.3.5.1 constructors:
928  /// All bits set to zero.
929  _GLIBCXX_CONSTEXPR bitset() _GLIBCXX_NOEXCEPT
930  { }
931 
932  /// Initial bits bitwise-copied from a single word (others set to zero).
933 #if __cplusplus >= 201103L
934  constexpr bitset(unsigned long long __val) noexcept
935  : _Base(_Sanitize_val<_Nb>::_S_do_sanitize_val(__val)) { }
936 #else
937  bitset(unsigned long __val)
938  : _Base(__val)
939  { _M_do_sanitize(); }
940 #endif
941 
942 #if _GLIBCXX_HOSTED
943  /**
944  * Use a subset of a string.
945  * @param __s A string of @a 0 and @a 1 characters.
946  * @param __position Index of the first character in @a __s to use;
947  * defaults to zero.
948  * @throw std::out_of_range If @a pos is bigger the size of @a __s.
949  * @throw std::invalid_argument If a character appears in the string
950  * which is neither @a 0 nor @a 1.
951  */
952  template<class _CharT, class _Traits, class _Alloc>
953  _GLIBCXX23_CONSTEXPR
954  explicit
955  bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
956  size_t __position = 0)
957  : _Base()
958  {
959  _M_check_initial_position(__s, __position);
960  _M_copy_from_string(__s, __position,
961  std::basic_string<_CharT, _Traits, _Alloc>::npos,
962  _CharT('0'), _CharT('1'));
963  }
964 
965  /**
966  * Use a subset of a string.
967  * @param __s A string of @a 0 and @a 1 characters.
968  * @param __position Index of the first character in @a __s to use.
969  * @param __n The number of characters to copy.
970  * @throw std::out_of_range If @a __position is bigger the size
971  * of @a __s.
972  * @throw std::invalid_argument If a character appears in the string
973  * which is neither @a 0 nor @a 1.
974  */
975  template<class _CharT, class _Traits, class _Alloc>
976  _GLIBCXX23_CONSTEXPR
977  bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
978  size_t __position, size_t __n)
979  : _Base()
980  {
981  _M_check_initial_position(__s, __position);
982  _M_copy_from_string(__s, __position, __n, _CharT('0'), _CharT('1'));
983  }
984 
985  // _GLIBCXX_RESOLVE_LIB_DEFECTS
986  // 396. what are characters zero and one.
987  template<class _CharT, class _Traits, class _Alloc>
988  _GLIBCXX23_CONSTEXPR
989  bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
990  size_t __position, size_t __n,
991  _CharT __zero, _CharT __one = _CharT('1'))
992  : _Base()
993  {
994  _M_check_initial_position(__s, __position);
995  _M_copy_from_string(__s, __position, __n, __zero, __one);
996  }
997 #endif // HOSTED
998 
999 #if __cplusplus >= 201103L
1000  /**
1001  * Construct from a character %array.
1002  * @param __str An %array of characters @a zero and @a one.
1003  * @param __n The number of characters to use.
1004  * @param __zero The character corresponding to the value 0.
1005  * @param __one The character corresponding to the value 1.
1006  * @throw std::invalid_argument If a character appears in the string
1007  * which is neither @a __zero nor @a __one.
1008  */
1009  template<typename _CharT>
1010  [[__gnu__::__nonnull__]]
1011  _GLIBCXX23_CONSTEXPR
1012  explicit
1013  bitset(const _CharT* __str,
1014  typename __bitset::__string<_CharT>::size_type __n
1015  = __bitset::__string<_CharT>::npos,
1016  _CharT __zero = _CharT('0'), _CharT __one = _CharT('1'))
1017  : _Base()
1018  {
1019 #if _GLIBCXX_HOSTED
1020  if (!__str)
1021  __throw_logic_error(__N("bitset::bitset(const _CharT*, ...)"));
1022 #endif
1023  using _Traits = typename __bitset::__string<_CharT>::traits_type;
1024 
1025  if (__n == __bitset::__string<_CharT>::npos)
1026  __n = _Traits::length(__str);
1027  _M_copy_from_ptr<_CharT, _Traits>(__str, __n, 0, __n, __zero, __one);
1028  }
1029 #endif // C++11
1030 
1031  // 23.3.5.2 bitset operations:
1032  ///@{
1033  /**
1034  * Operations on bitsets.
1035  * @param __rhs A same-sized bitset.
1036  *
1037  * These should be self-explanatory.
1038  */
1039  _GLIBCXX23_CONSTEXPR
1040  bitset<_Nb>&
1041  operator&=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
1042  {
1043  this->_M_do_and(__rhs);
1044  return *this;
1045  }
1046 
1047  _GLIBCXX23_CONSTEXPR
1048  bitset<_Nb>&
1049  operator|=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
1050  {
1051  this->_M_do_or(__rhs);
1052  return *this;
1053  }
1054 
1055  _GLIBCXX23_CONSTEXPR
1056  bitset<_Nb>&
1057  operator^=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
1058  {
1059  this->_M_do_xor(__rhs);
1060  return *this;
1061  }
1062  ///@}
1063 
1064  ///@{
1065  /**
1066  * Operations on bitsets.
1067  * @param __position The number of places to shift.
1068  *
1069  * These should be self-explanatory.
1070  */
1071  _GLIBCXX23_CONSTEXPR
1072  bitset<_Nb>&
1073  operator<<=(size_t __position) _GLIBCXX_NOEXCEPT
1074  {
1075  if (__builtin_expect(__position < _Nb, 1))
1076  {
1077  this->_M_do_left_shift(__position);
1078  this->_M_do_sanitize();
1079  }
1080  else
1081  this->_M_do_reset();
1082  return *this;
1083  }
1084 
1085  _GLIBCXX23_CONSTEXPR
1086  bitset<_Nb>&
1087  operator>>=(size_t __position) _GLIBCXX_NOEXCEPT
1088  {
1089  if (__builtin_expect(__position < _Nb, 1))
1090  {
1091  this->_M_do_right_shift(__position);
1092  this->_M_do_sanitize();
1093  }
1094  else
1095  this->_M_do_reset();
1096  return *this;
1097  }
1098  ///@}
1099 
1100  ///@{
1101  /**
1102  * These versions of single-bit set, reset, flip, and test are
1103  * extensions from the SGI version. They do no range checking.
1104  * @ingroup SGIextensions
1105  */
1106  _GLIBCXX23_CONSTEXPR
1107  bitset<_Nb>&
1108  _Unchecked_set(size_t __pos) _GLIBCXX_NOEXCEPT
1109  {
1110  this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
1111  return *this;
1112  }
1113 
1114  _GLIBCXX23_CONSTEXPR
1115  bitset<_Nb>&
1116  _Unchecked_set(size_t __pos, int __val) _GLIBCXX_NOEXCEPT
1117  {
1118  if (__val)
1119  this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
1120  else
1121  this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
1122  return *this;
1123  }
1124 
1125  _GLIBCXX23_CONSTEXPR
1126  bitset<_Nb>&
1127  _Unchecked_reset(size_t __pos) _GLIBCXX_NOEXCEPT
1128  {
1129  this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
1130  return *this;
1131  }
1132 
1133  _GLIBCXX23_CONSTEXPR
1134  bitset<_Nb>&
1135  _Unchecked_flip(size_t __pos) _GLIBCXX_NOEXCEPT
1136  {
1137  this->_M_getword(__pos) ^= _Base::_S_maskbit(__pos);
1138  return *this;
1139  }
1140 
1141  _GLIBCXX_CONSTEXPR bool
1142  _Unchecked_test(size_t __pos) const _GLIBCXX_NOEXCEPT
1143  { return ((this->_M_getword(__pos) & _Base::_S_maskbit(__pos))
1144  != static_cast<_WordT>(0)); }
1145  ///@}
1146 
1147  // Set, reset, and flip.
1148  /**
1149  * @brief Sets every bit to true.
1150  */
1151  _GLIBCXX23_CONSTEXPR
1152  bitset<_Nb>&
1153  set() _GLIBCXX_NOEXCEPT
1154  {
1155  this->_M_do_set();
1156  this->_M_do_sanitize();
1157  return *this;
1158  }
1159 
1160  /**
1161  * @brief Sets a given bit to a particular value.
1162  * @param __position The index of the bit.
1163  * @param __val Either true or false, defaults to true.
1164  * @throw std::out_of_range If @a pos is bigger the size of the %set.
1165  */
1166  _GLIBCXX23_CONSTEXPR
1167  bitset<_Nb>&
1168  set(size_t __position, bool __val = true)
1169  {
1170  this->_M_check(__position, __N("bitset::set"));
1171  return _Unchecked_set(__position, __val);
1172  }
1173 
1174  /**
1175  * @brief Sets every bit to false.
1176  */
1177  _GLIBCXX23_CONSTEXPR
1178  bitset<_Nb>&
1179  reset() _GLIBCXX_NOEXCEPT
1180  {
1181  this->_M_do_reset();
1182  return *this;
1183  }
1184 
1185  /**
1186  * @brief Sets a given bit to false.
1187  * @param __position The index of the bit.
1188  * @throw std::out_of_range If @a pos is bigger the size of the %set.
1189  *
1190  * Same as writing @c set(pos,false).
1191  */
1192  _GLIBCXX23_CONSTEXPR
1193  bitset<_Nb>&
1194  reset(size_t __position)
1195  {
1196  this->_M_check(__position, __N("bitset::reset"));
1197  return _Unchecked_reset(__position);
1198  }
1199 
1200  /**
1201  * @brief Toggles every bit to its opposite value.
1202  */
1203  _GLIBCXX23_CONSTEXPR
1204  bitset<_Nb>&
1205  flip() _GLIBCXX_NOEXCEPT
1206  {
1207  this->_M_do_flip();
1208  this->_M_do_sanitize();
1209  return *this;
1210  }
1211 
1212  /**
1213  * @brief Toggles a given bit to its opposite value.
1214  * @param __position The index of the bit.
1215  * @throw std::out_of_range If @a pos is bigger the size of the %set.
1216  */
1217  _GLIBCXX23_CONSTEXPR
1218  bitset<_Nb>&
1219  flip(size_t __position)
1220  {
1221  this->_M_check(__position, __N("bitset::flip"));
1222  return _Unchecked_flip(__position);
1223  }
1224 
1225  /// See the no-argument flip().
1226  _GLIBCXX23_CONSTEXPR
1227  bitset<_Nb>
1228  operator~() const _GLIBCXX_NOEXCEPT
1229  { return bitset<_Nb>(*this).flip(); }
1230 
1231  ///@{
1232  /**
1233  * @brief Array-indexing support.
1234  * @param __position Index into the %bitset.
1235  * @return A bool for a <em>const %bitset</em>. For non-const
1236  * bitsets, an instance of the reference proxy class.
1237  * @note These operators do no range checking and throw no exceptions,
1238  * as required by DR 11 to the standard.
1239  *
1240  * _GLIBCXX_RESOLVE_LIB_DEFECTS Note that this implementation already
1241  * resolves DR 11 (items 1 and 2), but does not do the range-checking
1242  * required by that DR's resolution. -pme
1243  * The DR has since been changed: range-checking is a precondition
1244  * (users' responsibility), and these functions must not throw. -pme
1245  */
1246  _GLIBCXX23_CONSTEXPR
1247  reference
1248  operator[](size_t __position)
1249  { return reference(*this, __position); }
1250 
1251  _GLIBCXX_CONSTEXPR bool
1252  operator[](size_t __position) const
1253  { return _Unchecked_test(__position); }
1254  ///@}
1255 
1256  /**
1257  * @brief Returns a numerical interpretation of the %bitset.
1258  * @return The integral equivalent of the bits.
1259  * @throw std::overflow_error If there are too many bits to be
1260  * represented in an @c unsigned @c long.
1261  */
1262  _GLIBCXX23_CONSTEXPR
1263  unsigned long
1264  to_ulong() const
1265  { return this->_M_do_to_ulong(); }
1266 
1267 #if __cplusplus >= 201103L
1268  _GLIBCXX23_CONSTEXPR
1269  unsigned long long
1270  to_ullong() const
1271  { return this->_M_do_to_ullong(); }
1272 #endif
1273 
1274 #if _GLIBCXX_HOSTED
1275  /**
1276  * @brief Returns a character interpretation of the %bitset.
1277  * @return The string equivalent of the bits.
1278  *
1279  * Note the ordering of the bits: decreasing character positions
1280  * correspond to increasing bit positions (see the main class notes for
1281  * an example).
1282  */
1283  template<class _CharT, class _Traits, class _Alloc>
1284  _GLIBCXX23_CONSTEXPR
1285  std::basic_string<_CharT, _Traits, _Alloc>
1286  to_string() const
1287  {
1288  std::basic_string<_CharT, _Traits, _Alloc> __result;
1289  _M_copy_to_string(__result, _CharT('0'), _CharT('1'));
1290  return __result;
1291  }
1292 
1293  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1294  // 396. what are characters zero and one.
1295  template<class _CharT, class _Traits, class _Alloc>
1296  _GLIBCXX23_CONSTEXPR
1297  std::basic_string<_CharT, _Traits, _Alloc>
1298  to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1299  {
1300  std::basic_string<_CharT, _Traits, _Alloc> __result;
1301  _M_copy_to_string(__result, __zero, __one);
1302  return __result;
1303  }
1304 
1305  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1306  // 434. bitset::to_string() hard to use.
1307  template<class _CharT, class _Traits>
1308  _GLIBCXX23_CONSTEXPR
1309  std::basic_string<_CharT, _Traits, std::allocator<_CharT> >
1310  to_string() const
1311  { return to_string<_CharT, _Traits, std::allocator<_CharT> >(); }
1312 
1313  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1314  // 853. to_string needs updating with zero and one.
1315  template<class _CharT, class _Traits>
1316  _GLIBCXX23_CONSTEXPR
1317  std::basic_string<_CharT, _Traits, std::allocator<_CharT> >
1318  to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1319  { return to_string<_CharT, _Traits,
1320  std::allocator<_CharT> >(__zero, __one); }
1321 
1322  template<class _CharT>
1323  _GLIBCXX23_CONSTEXPR
1324  std::basic_string<_CharT, std::char_traits<_CharT>,
1325  std::allocator<_CharT> >
1326  to_string() const
1327  {
1328  return to_string<_CharT, std::char_traits<_CharT>,
1329  std::allocator<_CharT> >();
1330  }
1331 
1332  template<class _CharT>
1333  _GLIBCXX23_CONSTEXPR
1334  std::basic_string<_CharT, std::char_traits<_CharT>,
1335  std::allocator<_CharT> >
1336  to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1337  {
1338  return to_string<_CharT, std::char_traits<_CharT>,
1339  std::allocator<_CharT> >(__zero, __one);
1340  }
1341 
1342  _GLIBCXX23_CONSTEXPR
1343  std::basic_string<char, std::char_traits<char>, std::allocator<char> >
1344  to_string() const
1345  {
1346  return to_string<char, std::char_traits<char>,
1347  std::allocator<char> >();
1348  }
1349 
1350  _GLIBCXX23_CONSTEXPR
1351  std::basic_string<char, std::char_traits<char>, std::allocator<char> >
1352  to_string(char __zero, char __one = '1') const
1353  {
1354  return to_string<char, std::char_traits<char>,
1355  std::allocator<char> >(__zero, __one);
1356  }
1357 #endif // HOSTED
1358 
1359  /// Returns the number of bits which are set.
1360  _GLIBCXX23_CONSTEXPR
1361  size_t
1362  count() const _GLIBCXX_NOEXCEPT
1363  { return this->_M_do_count(); }
1364 
1365  /// Returns the total number of bits.
1366  _GLIBCXX_CONSTEXPR size_t
1367  size() const _GLIBCXX_NOEXCEPT
1368  { return _Nb; }
1369 
1370  ///@{
1371  /// These comparisons for equality/inequality are, well, @e bitwise.
1372  _GLIBCXX23_CONSTEXPR
1373  bool
1374  operator==(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
1375  { return this->_M_is_equal(__rhs); }
1376 
1377 #if __cpp_impl_three_way_comparison < 201907L
1378  _GLIBCXX23_CONSTEXPR
1379  bool
1380  operator!=(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
1381  { return !this->_M_is_equal(__rhs); }
1382 #endif
1383  ///@}
1384 
1385  /**
1386  * @brief Tests the value of a bit.
1387  * @param __position The index of a bit.
1388  * @return The value at @a pos.
1389  * @throw std::out_of_range If @a pos is bigger the size of the %set.
1390  */
1391  _GLIBCXX23_CONSTEXPR
1392  bool
1393  test(size_t __position) const
1394  {
1395  this->_M_check(__position, __N("bitset::test"));
1396  return _Unchecked_test(__position);
1397  }
1398 
1399  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1400  // DR 693. std::bitset::all() missing.
1401  /**
1402  * @brief Tests whether all the bits are on.
1403  * @return True if all the bits are set.
1404  */
1405  _GLIBCXX23_CONSTEXPR
1406  bool
1407  all() const _GLIBCXX_NOEXCEPT
1408  { return this->template _M_are_all<_Nb>(); }
1409 
1410  /**
1411  * @brief Tests whether any of the bits are on.
1412  * @return True if at least one bit is set.
1413  */
1414  _GLIBCXX23_CONSTEXPR
1415  bool
1416  any() const _GLIBCXX_NOEXCEPT
1417  { return this->_M_is_any(); }
1418 
1419  /**
1420  * @brief Tests whether any of the bits are on.
1421  * @return True if none of the bits are set.
1422  */
1423  _GLIBCXX23_CONSTEXPR
1424  bool
1425  none() const _GLIBCXX_NOEXCEPT
1426  { return !this->_M_is_any(); }
1427 
1428  ///@{
1429  /// Self-explanatory.
1430  _GLIBCXX23_CONSTEXPR
1431  bitset<_Nb>
1432  operator<<(size_t __position) const _GLIBCXX_NOEXCEPT
1433  { return bitset<_Nb>(*this) <<= __position; }
1434 
1435  _GLIBCXX23_CONSTEXPR
1436  bitset<_Nb>
1437  operator>>(size_t __position) const _GLIBCXX_NOEXCEPT
1438  { return bitset<_Nb>(*this) >>= __position; }
1439  ///@}
1440 
1441  /**
1442  * @brief Finds the index of the first "on" bit.
1443  * @return The index of the first bit set, or size() if not found.
1444  * @ingroup SGIextensions
1445  * @sa _Find_next
1446  */
1447  _GLIBCXX23_CONSTEXPR
1448  size_t
1449  _Find_first() const _GLIBCXX_NOEXCEPT
1450  { return this->_M_do_find_first(_Nb); }
1451 
1452  /**
1453  * @brief Finds the index of the next "on" bit after prev.
1454  * @return The index of the next bit set, or size() if not found.
1455  * @param __prev Where to start searching.
1456  * @ingroup SGIextensions
1457  * @sa _Find_first
1458  */
1459  _GLIBCXX23_CONSTEXPR
1460  size_t
1461  _Find_next(size_t __prev) const _GLIBCXX_NOEXCEPT
1462  { return this->_M_do_find_next(__prev, _Nb); }
1463 
1464  private:
1465  // Helper functions for string operations.
1466  template<class _CharT, class _Traits>
1467  _GLIBCXX23_CONSTEXPR
1468  void
1469  _M_copy_from_ptr(const _CharT*, size_t, size_t, size_t,
1470  _CharT, _CharT);
1471 
1472 #if _GLIBCXX_HOSTED
1473  template<class _CharT, class _Traits, class _Alloc>
1474  _GLIBCXX23_CONSTEXPR
1475  void
1476  _M_copy_from_string(const std::basic_string<_CharT,
1477  _Traits, _Alloc>& __s, size_t __pos, size_t __n,
1478  _CharT __zero, _CharT __one)
1479  { _M_copy_from_ptr<_CharT, _Traits>(__s.data(), __s.size(), __pos, __n,
1480  __zero, __one); }
1481 
1482  template<class _CharT, class _Traits, class _Alloc>
1483  _GLIBCXX23_CONSTEXPR
1484  void
1485  _M_copy_to_string(std::basic_string<_CharT, _Traits, _Alloc>&,
1486  _CharT, _CharT) const;
1487 
1488  template<class _CharT, class _Traits, size_t _Nb2>
1489  friend std::basic_istream<_CharT, _Traits>&
1490  operator>>(std::basic_istream<_CharT, _Traits>&, bitset<_Nb2>&);
1491 
1492  template <class _CharT, class _Traits, size_t _Nb2>
1493  friend std::basic_ostream<_CharT, _Traits>&
1494  operator<<(std::basic_ostream<_CharT, _Traits>&, const bitset<_Nb2>&);
1495 #endif
1496  };
1497 
1498  // Definitions of non-inline member functions.
1499  template<size_t _Nb>
1500  template<class _CharT, class _Traits>
1501  _GLIBCXX23_CONSTEXPR
1502  void
1503  bitset<_Nb>::
1504  _M_copy_from_ptr(const _CharT* __s, size_t __len,
1505  size_t __pos, size_t __n, _CharT __zero, _CharT __one)
1506  {
1507  reset();
1508  const size_t __nbits = std::min(_Nb, std::min(__n, size_t(__len - __pos)));
1509  for (size_t __i = __nbits; __i > 0; --__i)
1510  {
1511  const _CharT __c = __s[__pos + __nbits - __i];
1512  if (_Traits::eq(__c, __zero))
1513  ;
1514  else if (_Traits::eq(__c, __one))
1515  _Unchecked_set(__i - 1);
1516  else
1517  __throw_invalid_argument(__N("bitset::_M_copy_from_ptr"));
1518  }
1519  }
1520 
1521 #if _GLIBCXX_HOSTED
1522  template<size_t _Nb>
1523  template<class _CharT, class _Traits, class _Alloc>
1524  _GLIBCXX23_CONSTEXPR
1525  void
1526  bitset<_Nb>::
1527  _M_copy_to_string(std::basic_string<_CharT, _Traits, _Alloc>& __s,
1528  _CharT __zero, _CharT __one) const
1529  {
1530  __s.assign(_Nb, __zero);
1531  size_t __n = this->_Find_first();
1532  while (__n < _Nb)
1533  {
1534  __s[_Nb - __n - 1] = __one;
1535  __n = _Find_next(__n);
1536  }
1537  }
1538 #endif // HOSTED
1539 
1540  // 23.3.5.3 bitset operations:
1541  ///@{
1542  /**
1543  * @brief Global bitwise operations on bitsets.
1544  * @param __x A bitset.
1545  * @param __y A bitset of the same size as @a __x.
1546  * @return A new bitset.
1547  *
1548  * These should be self-explanatory.
1549  */
1550  template<size_t _Nb>
1551  _GLIBCXX23_CONSTEXPR
1552  inline bitset<_Nb>
1553  operator&(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1554  {
1555  bitset<_Nb> __result(__x);
1556  __result &= __y;
1557  return __result;
1558  }
1559 
1560  template<size_t _Nb>
1561  _GLIBCXX23_CONSTEXPR
1562  inline bitset<_Nb>
1563  operator|(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1564  {
1565  bitset<_Nb> __result(__x);
1566  __result |= __y;
1567  return __result;
1568  }
1569 
1570  template <size_t _Nb>
1571  _GLIBCXX23_CONSTEXPR
1572  inline bitset<_Nb>
1573  operator^(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1574  {
1575  bitset<_Nb> __result(__x);
1576  __result ^= __y;
1577  return __result;
1578  }
1579  ///@}
1580 
1581 #if _GLIBCXX_HOSTED
1582  ///@{
1583  /**
1584  * @brief Global I/O operators for bitsets.
1585  *
1586  * Direct I/O between streams and bitsets is supported. Output is
1587  * straightforward. Input will skip whitespace, only accept @a 0 and @a 1
1588  * characters, and will only extract as many digits as the %bitset will
1589  * hold.
1590  */
1591  template<class _CharT, class _Traits, size_t _Nb>
1592  std::basic_istream<_CharT, _Traits>&
1593  operator>>(std::basic_istream<_CharT, _Traits>& __is, bitset<_Nb>& __x)
1594  {
1595  typedef typename _Traits::char_type char_type;
1596  typedef std::basic_istream<_CharT, _Traits> __istream_type;
1597  typedef typename __istream_type::ios_base __ios_base;
1598 
1599  struct _Buffer
1600  {
1601  static _GLIBCXX_CONSTEXPR bool _S_use_alloca() { return _Nb <= 256; }
1602 
1603  explicit _Buffer(_CharT* __p) : _M_ptr(__p) { }
1604 
1605  ~_Buffer()
1606  {
1607  if _GLIBCXX17_CONSTEXPR (!_S_use_alloca())
1608  delete[] _M_ptr;
1609  }
1610 
1611  _CharT* const _M_ptr;
1612  };
1613  _CharT* __ptr;
1614  if _GLIBCXX17_CONSTEXPR (_Buffer::_S_use_alloca())
1615  __ptr = (_CharT*)__builtin_alloca(_Nb);
1616  else
1617  __ptr = new _CharT[_Nb];
1618  const _Buffer __buf(__ptr);
1619 
1620  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1621  // 303. Bitset input operator underspecified
1622  const char_type __zero = __is.widen('0');
1623  const char_type __one = __is.widen('1');
1624 
1625  typename __ios_base::iostate __state = __ios_base::goodbit;
1626  typename __istream_type::sentry __sentry(__is);
1627  if (__sentry)
1628  {
1629  __try
1630  {
1631  for (size_t __i = _Nb; __i > 0; --__i)
1632  {
1633  static typename _Traits::int_type __eof = _Traits::eof();
1634 
1635  typename _Traits::int_type __c1 = __is.rdbuf()->sbumpc();
1636  if (_Traits::eq_int_type(__c1, __eof))
1637  {
1638  __state |= __ios_base::eofbit;
1639  break;
1640  }
1641  else
1642  {
1643  const char_type __c2 = _Traits::to_char_type(__c1);
1644  if (_Traits::eq(__c2, __zero))
1645  *__ptr++ = __zero;
1646  else if (_Traits::eq(__c2, __one))
1647  *__ptr++ = __one;
1648  else if (_Traits::
1649  eq_int_type(__is.rdbuf()->sputbackc(__c2),
1650  __eof))
1651  {
1652  __state |= __ios_base::failbit;
1653  break;
1654  }
1655  }
1656  }
1657  }
1658  __catch(__cxxabiv1::__forced_unwind&)
1659  {
1660  __is._M_setstate(__ios_base::badbit);
1661  __throw_exception_again;
1662  }
1663  __catch(...)
1664  { __is._M_setstate(__ios_base::badbit); }
1665  }
1666 
1667  if _GLIBCXX17_CONSTEXPR (_Nb)
1668  {
1669  if (size_t __len = __ptr - __buf._M_ptr)
1670  __x.template _M_copy_from_ptr<_CharT, _Traits>(__buf._M_ptr, __len,
1671  0, __len,
1672  __zero, __one);
1673  else
1674  __state |= __ios_base::failbit;
1675  }
1676  if (__state)
1677  __is.setstate(__state);
1678  return __is;
1679  }
1680 
1681  template <class _CharT, class _Traits, size_t _Nb>
1682  std::basic_ostream<_CharT, _Traits>&
1683  operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1684  const bitset<_Nb>& __x)
1685  {
1686  std::basic_string<_CharT, _Traits> __tmp;
1687 
1688  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1689  // 396. what are characters zero and one.
1690  const ctype<_CharT>& __ct = use_facet<ctype<_CharT> >(__os.getloc());
1691  __x._M_copy_to_string(__tmp, __ct.widen('0'), __ct.widen('1'));
1692  return __os << __tmp;
1693  }
1694  ///@}
1695 #endif // HOSTED
1696 
1697 _GLIBCXX_END_NAMESPACE_CONTAINER
1698 } // namespace std
1699 
1700 #undef _GLIBCXX_BITSET_WORDS
1701 #undef _GLIBCXX_BITSET_BITS_PER_WORD
1702 #undef _GLIBCXX_BITSET_BITS_PER_ULL
1703 
1704 #if __cplusplus >= 201103L
1705 
1706 namespace std _GLIBCXX_VISIBILITY(default)
1707 {
1708 _GLIBCXX_BEGIN_NAMESPACE_VERSION
1709 
1710  // DR 1182.
1711  /// std::hash specialization for bitset.
1712  template<size_t _Nb>
1713  struct hash<_GLIBCXX_STD_C::bitset<_Nb>>
1714  : public __hash_base<size_t, _GLIBCXX_STD_C::bitset<_Nb>>
1715  {
1716  size_t
1717  operator()(const _GLIBCXX_STD_C::bitset<_Nb>& __b) const noexcept
1718  {
1719  const size_t __clength = (_Nb + __CHAR_BIT__ - 1) / __CHAR_BIT__;
1720  return std::_Hash_impl::hash(__b._M_getdata(), __clength);
1721  }
1722  };
1723 
1724  template<>
1725  struct hash<_GLIBCXX_STD_C::bitset<0>>
1726  : public __hash_base<size_t, _GLIBCXX_STD_C::bitset<0>>
1727  {
1728  size_t
1729  operator()(const _GLIBCXX_STD_C::bitset<0>&) const noexcept
1730  { return 0; }
1731  };
1732 
1733 _GLIBCXX_END_NAMESPACE_VERSION
1734 } // namespace
1735 
1736 #endif // C++11
1737 
1738 #if defined _GLIBCXX_DEBUG && _GLIBCXX_HOSTED
1739 # include <debug/bitset>
1740 #endif
1741 
1742 #endif /* _GLIBCXX_BITSET */