libstdc++

bitset
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1 // <bitset> -*- C++ -*-
2
3 // Copyright (C) 2001-2013 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
60 namespace 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 * The %bitset class represents a @e fixed-size sequence of bits.
685 *
686 * @ingroup containers
687 *
688 * (Note that %bitset does @e not meet the formal requirements of a
689 * <a href="tables.html#65">container</a>. Mainly, it lacks iterators.)
690 *
691 * The template argument, @a Nb, may be any non-negative number,
692 * specifying the number of bits (e.g., "0", "12", "1024*1024").
693 *
694 * In the general unoptimized case, storage is allocated in word-sized
695 * blocks. Let B be the number of bits in a word, then (Nb+(B-1))/B
696 * words will be used for storage. B - Nb%B bits are unused. (They are
697 * the high-order bits in the highest word.) It is a class invariant
698 * that those unused bits are always zero.
699 *
700 * If you think of %bitset as <em>a simple array of bits</em>, be
701 * aware that your mental picture is reversed: a %bitset behaves
702 * the same way as bits in integers do, with the bit at index 0 in
703 * the <em>least significant / right-hand</em> position, and the bit at
704 * index Nb-1 in the <em>most significant / left-hand</em> position.
705 * Thus, unlike other containers, a %bitset's index <em>counts from
706 * right to left</em>, to put it very loosely.
707 *
708 * This behavior is preserved when translating to and from strings. For
709 * example, the first line of the following program probably prints
710 * <em>b(&apos;a&apos;) is 0001100001</em> on a modern ASCII system.
711 *
712 * @code
713 * #include <bitset>
714 * #include <iostream>
715 * #include <sstream>
716 *
717 * using namespace std;
718 *
719 * int main()
720 * {
721 * long a = 'a';
722 * bitset<10> b(a);
723 *
724 * cout << "b('a') is " << b << endl;
725 *
726 * ostringstream s;
727 * s << b;
728 * string str = s.str();
729 * cout << "index 3 in the string is " << str[3] << " but\n"
730 * << "index 3 in the bitset is " << b[3] << endl;
731 * }
732 * @endcode
733 *
734 * Also see:
735 * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt12ch33s02.html
736 * for a description of extensions.
737 *
738 * Most of the actual code isn't contained in %bitset<> itself, but in the
739 * base class _Base_bitset. The base class works with whole words, not with
740 * individual bits. This allows us to specialize _Base_bitset for the
741 * important special case where the %bitset is only a single word.
742 *
743 * Extra confusion can result due to the fact that the storage for
744 * _Base_bitset @e is a regular array, and is indexed as such. This is
745 * carefully encapsulated.
746 */
747 template<size_t _Nb>
748 class bitset
749 : private _Base_bitset<_GLIBCXX_BITSET_WORDS(_Nb)>
750 {
751 private:
752 typedef _Base_bitset<_GLIBCXX_BITSET_WORDS(_Nb)> _Base;
753 typedef unsigned long _WordT;
754
755 void
756 _M_do_sanitize() _GLIBCXX_NOEXCEPT
757 {
758 typedef _Sanitize<_Nb % _GLIBCXX_BITSET_BITS_PER_WORD> __sanitize_type;
759 __sanitize_type::_S_do_sanitize(this->_M_hiword());
760 }
761
762 #if __cplusplus >= 201103L
763 template<typename> friend class hash;
764 #endif
765
766 public:
767 /**
768 * This encapsulates the concept of a single bit. An instance of this
769 * class is a proxy for an actual bit; this way the individual bit
770 * operations are done as faster word-size bitwise instructions.
771 *
772 * Most users will never need to use this class directly; conversions
773 * to and from bool are automatic and should be transparent. Overloaded
774 * operators help to preserve the illusion.
775 *
776 * (On a typical system, this <em>bit %reference</em> is 64
777 * times the size of an actual bit. Ha.)
778 */
779 class reference
780 {
781 friend class bitset;
782
783 _WordT* _M_wp;
784 size_t _M_bpos;
785
786 // left undefined
787 reference();
788
789 public:
790 reference(bitset& __b, size_t __pos) _GLIBCXX_NOEXCEPT
791 {
792 _M_wp = &__b._M_getword(__pos);
793 _M_bpos = _Base::_S_whichbit(__pos);
794 }
795
796 ~reference() _GLIBCXX_NOEXCEPT
797 { }
798
799 // For b[i] = __x;
800 reference&
801 operator=(bool __x) _GLIBCXX_NOEXCEPT
802 {
803 if (__x)
804 *_M_wp |= _Base::_S_maskbit(_M_bpos);
805 else
806 *_M_wp &= ~_Base::_S_maskbit(_M_bpos);
807 return *this;
808 }
809
810 // For b[i] = b[__j];
811 reference&
812 operator=(const reference& __j) _GLIBCXX_NOEXCEPT
813 {
814 if ((*(__j._M_wp) & _Base::_S_maskbit(__j._M_bpos)))
815 *_M_wp |= _Base::_S_maskbit(_M_bpos);
816 else
817 *_M_wp &= ~_Base::_S_maskbit(_M_bpos);
818 return *this;
819 }
820
821 // Flips the bit
822 bool
823 operator~() const _GLIBCXX_NOEXCEPT
824 { return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) == 0; }
825
826 // For __x = b[i];
827 operator bool() const _GLIBCXX_NOEXCEPT
828 { return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) != 0; }
829
830 // For b[i].flip();
831 reference&
832 flip() _GLIBCXX_NOEXCEPT
833 {
834 *_M_wp ^= _Base::_S_maskbit(_M_bpos);
835 return *this;
836 }
837 };
838 friend class reference;
839
840 // 23.3.5.1 constructors:
841 /// All bits set to zero.
842 _GLIBCXX_CONSTEXPR bitset() _GLIBCXX_NOEXCEPT
843 { }
844
845 /// Initial bits bitwise-copied from a single word (others set to zero).
846 #if __cplusplus >= 201103L
847 constexpr bitset(unsigned long long __val) noexcept
848 : _Base(_Sanitize_val<_Nb>::_S_do_sanitize_val(__val)) { }
849 #else
850 bitset(unsigned long __val)
851 : _Base(__val)
852 { _M_do_sanitize(); }
853 #endif
854
855 /**
856 * Use a subset of a string.
857 * @param __s A string of @a 0 and @a 1 characters.
858 * @param __position Index of the first character in @a __s to use;
859 * defaults to zero.
860 * @throw std::out_of_range If @a pos is bigger the size of @a __s.
861 * @throw std::invalid_argument If a character appears in the string
862 * which is neither @a 0 nor @a 1.
863 */
864 template<class _CharT, class _Traits, class _Alloc>
865 explicit
866 bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
867 size_t __position = 0)
868 : _Base()
869 {
870 if (__position > __s.size())
871 __throw_out_of_range(__N("bitset::bitset initial position "
872 "not valid"));
873 _M_copy_from_string(__s, __position,
874 std::basic_string<_CharT, _Traits, _Alloc>::npos,
875 _CharT('0'), _CharT('1'));
876 }
877
878 /**
879 * Use a subset of a string.
880 * @param __s A string of @a 0 and @a 1 characters.
881 * @param __position Index of the first character in @a __s to use.
882 * @param __n The number of characters to copy.
883 * @throw std::out_of_range If @a __position is bigger the size
884 * of @a __s.
885 * @throw std::invalid_argument If a character appears in the string
886 * which is neither @a 0 nor @a 1.
887 */
888 template<class _CharT, class _Traits, class _Alloc>
889 bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
890 size_t __position, size_t __n)
891 : _Base()
892 {
893 if (__position > __s.size())
894 __throw_out_of_range(__N("bitset::bitset initial position "
895 "not valid"));
896 _M_copy_from_string(__s, __position, __n, _CharT('0'), _CharT('1'));
897 }
898
899 // _GLIBCXX_RESOLVE_LIB_DEFECTS
900 // 396. what are characters zero and one.
901 template<class _CharT, class _Traits, class _Alloc>
902 bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
903 size_t __position, size_t __n,
904 _CharT __zero, _CharT __one = _CharT('1'))
905 : _Base()
906 {
907 if (__position > __s.size())
908 __throw_out_of_range(__N("bitset::bitset initial position "
909 "not valid"));
910 _M_copy_from_string(__s, __position, __n, __zero, __one);
911 }
912
913 #if __cplusplus >= 201103L
914 /**
915 * Construct from a character %array.
916 * @param __str An %array of characters @a zero and @a one.
917 * @param __n The number of characters to use.
918 * @param __zero The character corresponding to the value 0.
919 * @param __one The character corresponding to the value 1.
920 * @throw std::invalid_argument If a character appears in the string
921 * which is neither @a __zero nor @a __one.
922 */
923 template<typename _CharT>
924 explicit
925 bitset(const _CharT* __str,
926 typename std::basic_string<_CharT>::size_type __n
927 = std::basic_string<_CharT>::npos,
928 _CharT __zero = _CharT('0'), _CharT __one = _CharT('1'))
929 : _Base()
930 {
931 if (!__str)
932 __throw_logic_error(__N("bitset::bitset(const _CharT*, ...)"));
933
934 if (__n == std::basic_string<_CharT>::npos)
935 __n = std::char_traits<_CharT>::length(__str);
936 _M_copy_from_ptr<_CharT, std::char_traits<_CharT>>(__str, __n, 0,
937 __n, __zero,
938 __one);
939 }
940 #endif
941
942 // 23.3.5.2 bitset operations:
943 //@{
944 /**
945 * Operations on bitsets.
946 * @param __rhs A same-sized bitset.
947 *
948 * These should be self-explanatory.
949 */
950 bitset<_Nb>&
951 operator&=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
952 {
953 this->_M_do_and(__rhs);
954 return *this;
955 }
956
957 bitset<_Nb>&
958 operator|=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
959 {
960 this->_M_do_or(__rhs);
961 return *this;
962 }
963
964 bitset<_Nb>&
965 operator^=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
966 {
967 this->_M_do_xor(__rhs);
968 return *this;
969 }
970 //@}
971
972 //@{
973 /**
974 * Operations on bitsets.
975 * @param __position The number of places to shift.
976 *
977 * These should be self-explanatory.
978 */
979 bitset<_Nb>&
980 operator<<=(size_t __position) _GLIBCXX_NOEXCEPT
981 {
982 if (__builtin_expect(__position < _Nb, 1))
983 {
984 this->_M_do_left_shift(__position);
985 this->_M_do_sanitize();
986 }
987 else
988 this->_M_do_reset();
989 return *this;
990 }
991
992 bitset<_Nb>&
993 operator>>=(size_t __position) _GLIBCXX_NOEXCEPT
994 {
995 if (__builtin_expect(__position < _Nb, 1))
996 {
997 this->_M_do_right_shift(__position);
998 this->_M_do_sanitize();
999 }
1000 else
1001 this->_M_do_reset();
1002 return *this;
1003 }
1004 //@}
1005
1006 //@{
1007 /**
1008 * These versions of single-bit set, reset, flip, and test are
1009 * extensions from the SGI version. They do no range checking.
1010 * @ingroup SGIextensions
1011 */
1012 bitset<_Nb>&
1013 _Unchecked_set(size_t __pos) _GLIBCXX_NOEXCEPT
1014 {
1015 this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
1016 return *this;
1017 }
1018
1019 bitset<_Nb>&
1020 _Unchecked_set(size_t __pos, int __val) _GLIBCXX_NOEXCEPT
1021 {
1022 if (__val)
1023 this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
1024 else
1025 this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
1026 return *this;
1027 }
1028
1029 bitset<_Nb>&
1030 _Unchecked_reset(size_t __pos) _GLIBCXX_NOEXCEPT
1031 {
1032 this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
1033 return *this;
1034 }
1035
1036 bitset<_Nb>&
1037 _Unchecked_flip(size_t __pos) _GLIBCXX_NOEXCEPT
1038 {
1039 this->_M_getword(__pos) ^= _Base::_S_maskbit(__pos);
1040 return *this;
1041 }
1042
1043 _GLIBCXX_CONSTEXPR bool
1044 _Unchecked_test(size_t __pos) const _GLIBCXX_NOEXCEPT
1045 { return ((this->_M_getword(__pos) & _Base::_S_maskbit(__pos))
1046 != static_cast<_WordT>(0)); }
1047 //@}
1048
1049 // Set, reset, and flip.
1050 /**
1051 * @brief Sets every bit to true.
1052 */
1053 bitset<_Nb>&
1054 set() _GLIBCXX_NOEXCEPT
1055 {
1056 this->_M_do_set();
1057 this->_M_do_sanitize();
1058 return *this;
1059 }
1060
1061 /**
1062 * @brief Sets a given bit to a particular value.
1063 * @param __position The index of the bit.
1064 * @param __val Either true or false, defaults to true.
1065 * @throw std::out_of_range If @a pos is bigger the size of the %set.
1066 */
1067 bitset<_Nb>&
1068 set(size_t __position, bool __val = true)
1069 {
1070 if (__position >= _Nb)
1071 __throw_out_of_range(__N("bitset::set"));
1072 return _Unchecked_set(__position, __val);
1073 }
1074
1075 /**
1076 * @brief Sets every bit to false.
1077 */
1078 bitset<_Nb>&
1079 reset() _GLIBCXX_NOEXCEPT
1080 {
1081 this->_M_do_reset();
1082 return *this;
1083 }
1084
1085 /**
1086 * @brief Sets a given bit to false.
1087 * @param __position The index of the bit.
1088 * @throw std::out_of_range If @a pos is bigger the size of the %set.
1089 *
1090 * Same as writing @c set(pos,false).
1091 */
1092 bitset<_Nb>&
1093 reset(size_t __position)
1094 {
1095 if (__position >= _Nb)
1096 __throw_out_of_range(__N("bitset::reset"));
1097 return _Unchecked_reset(__position);
1098 }
1099
1100 /**
1101 * @brief Toggles every bit to its opposite value.
1102 */
1103 bitset<_Nb>&
1104 flip() _GLIBCXX_NOEXCEPT
1105 {
1106 this->_M_do_flip();
1107 this->_M_do_sanitize();
1108 return *this;
1109 }
1110
1111 /**
1112 * @brief Toggles a given bit to its opposite value.
1113 * @param __position The index of the bit.
1114 * @throw std::out_of_range If @a pos is bigger the size of the %set.
1115 */
1116 bitset<_Nb>&
1117 flip(size_t __position)
1118 {
1119 if (__position >= _Nb)
1120 __throw_out_of_range(__N("bitset::flip"));
1121 return _Unchecked_flip(__position);
1122 }
1123
1124 /// See the no-argument flip().
1125 bitset<_Nb>
1126 operator~() const _GLIBCXX_NOEXCEPT
1127 { return bitset<_Nb>(*this).flip(); }
1128
1129 //@{
1130 /**
1131 * @brief Array-indexing support.
1132 * @param __position Index into the %bitset.
1133 * @return A bool for a <em>const %bitset</em>. For non-const
1134 * bitsets, an instance of the reference proxy class.
1135 * @note These operators do no range checking and throw no exceptions,
1136 * as required by DR 11 to the standard.
1137 *
1138 * _GLIBCXX_RESOLVE_LIB_DEFECTS Note that this implementation already
1139 * resolves DR 11 (items 1 and 2), but does not do the range-checking
1140 * required by that DR's resolution. -pme
1141 * The DR has since been changed: range-checking is a precondition
1142 * (users' responsibility), and these functions must not throw. -pme
1143 */
1144 reference
1145 operator[](size_t __position)
1146 { return reference(*this, __position); }
1147
1148 _GLIBCXX_CONSTEXPR bool
1149 operator[](size_t __position) const
1150 { return _Unchecked_test(__position); }
1151 //@}
1152
1153 /**
1154 * @brief Returns a numerical interpretation of the %bitset.
1155 * @return The integral equivalent of the bits.
1156 * @throw std::overflow_error If there are too many bits to be
1157 * represented in an @c unsigned @c long.
1158 */
1159 unsigned long
1160 to_ulong() const
1161 { return this->_M_do_to_ulong(); }
1162
1163 #if __cplusplus >= 201103L
1164 unsigned long long
1165 to_ullong() const
1166 { return this->_M_do_to_ullong(); }
1167 #endif
1168
1169 /**
1170 * @brief Returns a character interpretation of the %bitset.
1171 * @return The string equivalent of the bits.
1172 *
1173 * Note the ordering of the bits: decreasing character positions
1174 * correspond to increasing bit positions (see the main class notes for
1175 * an example).
1176 */
1177 template<class _CharT, class _Traits, class _Alloc>
1178 std::basic_string<_CharT, _Traits, _Alloc>
1179 to_string() const
1180 {
1181 std::basic_string<_CharT, _Traits, _Alloc> __result;
1182 _M_copy_to_string(__result, _CharT('0'), _CharT('1'));
1183 return __result;
1184 }
1185
1186 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1187 // 396. what are characters zero and one.
1188 template<class _CharT, class _Traits, class _Alloc>
1189 std::basic_string<_CharT, _Traits, _Alloc>
1190 to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1191 {
1192 std::basic_string<_CharT, _Traits, _Alloc> __result;
1193 _M_copy_to_string(__result, __zero, __one);
1194 return __result;
1195 }
1196
1197 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1198 // 434. bitset::to_string() hard to use.
1199 template<class _CharT, class _Traits>
1200 std::basic_string<_CharT, _Traits, std::allocator<_CharT> >
1201 to_string() const
1202 { return to_string<_CharT, _Traits, std::allocator<_CharT> >(); }
1203
1204 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1205 // 853. to_string needs updating with zero and one.
1206 template<class _CharT, class _Traits>
1207 std::basic_string<_CharT, _Traits, std::allocator<_CharT> >
1208 to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1209 { return to_string<_CharT, _Traits,
1210 std::allocator<_CharT> >(__zero, __one); }
1211
1212 template<class _CharT>
1213 std::basic_string<_CharT, std::char_traits<_CharT>,
1214 std::allocator<_CharT> >
1215 to_string() const
1216 {
1217 return to_string<_CharT, std::char_traits<_CharT>,
1218 std::allocator<_CharT> >();
1219 }
1220
1221 template<class _CharT>
1222 std::basic_string<_CharT, std::char_traits<_CharT>,
1223 std::allocator<_CharT> >
1224 to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1225 {
1226 return to_string<_CharT, std::char_traits<_CharT>,
1227 std::allocator<_CharT> >(__zero, __one);
1228 }
1229
1230 std::basic_string<char, std::char_traits<char>, std::allocator<char> >
1231 to_string() const
1232 {
1233 return to_string<char, std::char_traits<char>,
1234 std::allocator<char> >();
1235 }
1236
1237 std::basic_string<char, std::char_traits<char>, std::allocator<char> >
1238 to_string(char __zero, char __one = '1') const
1239 {
1240 return to_string<char, std::char_traits<char>,
1241 std::allocator<char> >(__zero, __one);
1242 }
1243
1244 // Helper functions for string operations.
1245 template<class _CharT, class _Traits>
1246 void
1247 _M_copy_from_ptr(const _CharT*, size_t, size_t, size_t,
1248 _CharT, _CharT);
1249
1250 template<class _CharT, class _Traits, class _Alloc>
1251 void
1252 _M_copy_from_string(const std::basic_string<_CharT,
1253 _Traits, _Alloc>& __s, size_t __pos, size_t __n,
1254 _CharT __zero, _CharT __one)
1255 { _M_copy_from_ptr<_CharT, _Traits>(__s.data(), __s.size(), __pos, __n,
1256 __zero, __one); }
1257
1258 template<class _CharT, class _Traits, class _Alloc>
1259 void
1260 _M_copy_to_string(std::basic_string<_CharT, _Traits, _Alloc>&,
1261 _CharT, _CharT) const;
1262
1263 // NB: Backward compat.
1264 template<class _CharT, class _Traits, class _Alloc>
1265 void
1266 _M_copy_from_string(const std::basic_string<_CharT,
1267 _Traits, _Alloc>& __s, size_t __pos, size_t __n)
1268 { _M_copy_from_string(__s, __pos, __n, _CharT('0'), _CharT('1')); }
1269
1270 template<class _CharT, class _Traits, class _Alloc>
1271 void
1272 _M_copy_to_string(std::basic_string<_CharT, _Traits,_Alloc>& __s) const
1273 { _M_copy_to_string(__s, _CharT('0'), _CharT('1')); }
1274
1275 /// Returns the number of bits which are set.
1276 size_t
1277 count() const _GLIBCXX_NOEXCEPT
1278 { return this->_M_do_count(); }
1279
1280 /// Returns the total number of bits.
1281 _GLIBCXX_CONSTEXPR size_t
1282 size() const _GLIBCXX_NOEXCEPT
1283 { return _Nb; }
1284
1285 //@{
1286 /// These comparisons for equality/inequality are, well, @e bitwise.
1287 bool
1288 operator==(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
1289 { return this->_M_is_equal(__rhs); }
1290
1291 bool
1292 operator!=(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
1293 { return !this->_M_is_equal(__rhs); }
1294 //@}
1295
1296 /**
1297 * @brief Tests the value of a bit.
1298 * @param __position The index of a bit.
1299 * @return The value at @a pos.
1300 * @throw std::out_of_range If @a pos is bigger the size of the %set.
1301 */
1302 bool
1303 test(size_t __position) const
1304 {
1305 if (__position >= _Nb)
1306 __throw_out_of_range(__N("bitset::test"));
1307 return _Unchecked_test(__position);
1308 }
1309
1310 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1311 // DR 693. std::bitset::all() missing.
1312 /**
1313 * @brief Tests whether all the bits are on.
1314 * @return True if all the bits are set.
1315 */
1316 bool
1317 all() const _GLIBCXX_NOEXCEPT
1318 { return this->template _M_are_all<_Nb>(); }
1319
1320 /**
1321 * @brief Tests whether any of the bits are on.
1322 * @return True if at least one bit is set.
1323 */
1324 bool
1325 any() const _GLIBCXX_NOEXCEPT
1326 { return this->_M_is_any(); }
1327
1328 /**
1329 * @brief Tests whether any of the bits are on.
1330 * @return True if none of the bits are set.
1331 */
1332 bool
1333 none() const _GLIBCXX_NOEXCEPT
1334 { return !this->_M_is_any(); }
1335
1336 //@{
1337 /// Self-explanatory.
1338 bitset<_Nb>
1339 operator<<(size_t __position) const _GLIBCXX_NOEXCEPT
1340 { return bitset<_Nb>(*this) <<= __position; }
1341
1342 bitset<_Nb>
1343 operator>>(size_t __position) const _GLIBCXX_NOEXCEPT
1344 { return bitset<_Nb>(*this) >>= __position; }
1345 //@}
1346
1347 /**
1348 * @brief Finds the index of the first "on" bit.
1349 * @return The index of the first bit set, or size() if not found.
1350 * @ingroup SGIextensions
1351 * @sa _Find_next
1352 */
1353 size_t
1354 _Find_first() const _GLIBCXX_NOEXCEPT
1355 { return this->_M_do_find_first(_Nb); }
1356
1357 /**
1358 * @brief Finds the index of the next "on" bit after prev.
1359 * @return The index of the next bit set, or size() if not found.
1360 * @param __prev Where to start searching.
1361 * @ingroup SGIextensions
1362 * @sa _Find_first
1363 */
1364 size_t
1365 _Find_next(size_t __prev) const _GLIBCXX_NOEXCEPT
1366 { return this->_M_do_find_next(__prev, _Nb); }
1367 };
1368
1369 // Definitions of non-inline member functions.
1370 template<size_t _Nb>
1371 template<class _CharT, class _Traits>
1372 void
1373 bitset<_Nb>::
1374 _M_copy_from_ptr(const _CharT* __s, size_t __len,
1375 size_t __pos, size_t __n, _CharT __zero, _CharT __one)
1376 {
1377 reset();
1378 const size_t __nbits = std::min(_Nb, std::min(__n, size_t(__len - __pos)));
1379 for (size_t __i = __nbits; __i > 0; --__i)
1380 {
1381 const _CharT __c = __s[__pos + __nbits - __i];
1382 if (_Traits::eq(__c, __zero))
1383 ;
1384 else if (_Traits::eq(__c, __one))
1385 _Unchecked_set(__i - 1);
1386 else
1387 __throw_invalid_argument(__N("bitset::_M_copy_from_ptr"));
1388 }
1389 }
1390
1391 template<size_t _Nb>
1392 template<class _CharT, class _Traits, class _Alloc>
1393 void
1394 bitset<_Nb>::
1395 _M_copy_to_string(std::basic_string<_CharT, _Traits, _Alloc>& __s,
1396 _CharT __zero, _CharT __one) const
1397 {
1398 __s.assign(_Nb, __zero);
1399 for (size_t __i = _Nb; __i > 0; --__i)
1400 if (_Unchecked_test(__i - 1))
1401 _Traits::assign(__s[_Nb - __i], __one);
1402 }
1403
1404 // 23.3.5.3 bitset operations:
1405 //@{
1406 /**
1407 * @brief Global bitwise operations on bitsets.
1408 * @param __x A bitset.
1409 * @param __y A bitset of the same size as @a __x.
1410 * @return A new bitset.
1411 *
1412 * These should be self-explanatory.
1413 */
1414 template<size_t _Nb>
1415 inline bitset<_Nb>
1416 operator&(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1417 {
1418 bitset<_Nb> __result(__x);
1419 __result &= __y;
1420 return __result;
1421 }
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
1442 //@{
1443 /**
1444 * @brief Global I/O operators for bitsets.
1445 *
1446 * Direct I/O between streams and bitsets is supported. Output is
1447 * straightforward. Input will skip whitespace, only accept @a 0 and @a 1
1448 * characters, and will only extract as many digits as the %bitset will
1449 * hold.
1450 */
1451 template<class _CharT, class _Traits, size_t _Nb>
1452 std::basic_istream<_CharT, _Traits>&
1453 operator>>(std::basic_istream<_CharT, _Traits>& __is, bitset<_Nb>& __x)
1454 {
1455 typedef typename _Traits::char_type char_type;
1456 typedef std::basic_istream<_CharT, _Traits> __istream_type;
1457 typedef typename __istream_type::ios_base __ios_base;
1458
1459 std::basic_string<_CharT, _Traits> __tmp;
1460 __tmp.reserve(_Nb);
1461
1462 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1463 // 303. Bitset input operator underspecified
1464 const char_type __zero = __is.widen('0');
1465 const char_type __one = __is.widen('1');
1466
1467 typename __ios_base::iostate __state = __ios_base::goodbit;
1468 typename __istream_type::sentry __sentry(__is);
1469 if (__sentry)
1470 {
1471 __try
1472 {
1473 for (size_t __i = _Nb; __i > 0; --__i)
1474 {
1475 static typename _Traits::int_type __eof = _Traits::eof();
1476
1477 typename _Traits::int_type __c1 = __is.rdbuf()->sbumpc();
1478 if (_Traits::eq_int_type(__c1, __eof))
1479 {
1480 __state |= __ios_base::eofbit;
1481 break;
1482 }
1483 else
1484 {
1485 const char_type __c2 = _Traits::to_char_type(__c1);
1486 if (_Traits::eq(__c2, __zero))
1487 __tmp.push_back(__zero);
1488 else if (_Traits::eq(__c2, __one))
1489 __tmp.push_back(__one);
1490 else if (_Traits::
1491 eq_int_type(__is.rdbuf()->sputbackc(__c2),
1492 __eof))
1493 {
1494 __state |= __ios_base::failbit;
1495 break;
1496 }
1497 }
1498 }
1499 }
1500 __catch(__cxxabiv1::__forced_unwind&)
1501 {
1502 __is._M_setstate(__ios_base::badbit);
1503 __throw_exception_again;
1504 }
1505 __catch(...)
1506 { __is._M_setstate(__ios_base::badbit); }
1507 }
1508
1509 if (__tmp.empty() && _Nb)
1510 __state |= __ios_base::failbit;
1511 else
1512 __x._M_copy_from_string(__tmp, static_cast<size_t>(0), _Nb,
1513 __zero, __one);
1514 if (__state)
1515 __is.setstate(__state);
1516 return __is;
1517 }
1518
1519 template <class _CharT, class _Traits, size_t _Nb>
1520 std::basic_ostream<_CharT, _Traits>&
1521 operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1522 const bitset<_Nb>& __x)
1523 {
1524 std::basic_string<_CharT, _Traits> __tmp;
1525
1526 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1527 // 396. what are characters zero and one.
1528 const ctype<_CharT>& __ct = use_facet<ctype<_CharT> >(__os.getloc());
1529 __x._M_copy_to_string(__tmp, __ct.widen('0'), __ct.widen('1'));
1530 return __os << __tmp;
1531 }
1532 //@}
1533
1534 _GLIBCXX_END_NAMESPACE_CONTAINER
1535 } // namespace std
1536
1537 #undef _GLIBCXX_BITSET_WORDS
1538 #undef _GLIBCXX_BITSET_BITS_PER_WORD
1539 #undef _GLIBCXX_BITSET_BITS_PER_ULL
1540
1541 #if __cplusplus >= 201103L
1542
1543 #include <bits/functional_hash.h>
1544
1545 namespace std _GLIBCXX_VISIBILITY(default)
1546 {
1547 _GLIBCXX_BEGIN_NAMESPACE_VERSION
1548
1549 // DR 1182.
1550 /// std::hash specialization for bitset.
1551 template<size_t _Nb>
1552 struct hash<_GLIBCXX_STD_C::bitset<_Nb>>
1553 : public __hash_base<size_t, _GLIBCXX_STD_C::bitset<_Nb>>
1554 {
1555 size_t
1556 operator()(const _GLIBCXX_STD_C::bitset<_Nb>& __b) const noexcept
1557 {
1558 const size_t __clength = (_Nb + __CHAR_BIT__ - 1) / __CHAR_BIT__;
1559 return std::_Hash_impl::hash(__b._M_getdata(), __clength);
1560 }
1561 };
1562
1563 template<>
1564 struct hash<_GLIBCXX_STD_C::bitset<0>>
1565 : public __hash_base<size_t, _GLIBCXX_STD_C::bitset<0>>
1566 {
1567 size_t
1568 operator()(const _GLIBCXX_STD_C::bitset<0>&) const noexcept
1569 { return 0; }
1570 };
1571
1572 _GLIBCXX_END_NAMESPACE_VERSION
1573 } // namespace
1574
1575 #endif // C++11
1576
1577 #ifdef _GLIBCXX_DEBUG
1578 # include <debug/bitset>
1579 #endif
1580
1581 #ifdef _GLIBCXX_PROFILE
1582 # include <profile/bitset>
1583 #endif
1584
1585 #endif /* _GLIBCXX_BITSET */