| blob | c58da822493ab027b755aa29857c7225c9895e49 |
1 // <bitset> -*- C++ -*-
3 // Copyright (C) 2001-2014 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.
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.
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.
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/>.
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 */
38 /** @file include/bitset
39 * This is a Standard C++ Library header.
40 */
42 #ifndef _GLIBCXX_BITSET
43 #define _GLIBCXX_BITSET 1
45 #pragma GCC system_header
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>
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))
58 #define _GLIBCXX_BITSET_BITS_PER_ULL (__CHAR_BIT__ * __SIZEOF_LONG_LONG__)
60 namespace std _GLIBCXX_VISIBILITY(default)
61 {
62 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
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;
75 /// 0 is the least significant word.
76 _WordT _M_w[_Nw];
78 _GLIBCXX_CONSTEXPR _Base_bitset() _GLIBCXX_NOEXCEPT
79 : _M_w() { }
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
94 static _GLIBCXX_CONSTEXPR size_t
95 _S_whichword(size_t __pos) _GLIBCXX_NOEXCEPT
96 { return __pos / _GLIBCXX_BITSET_BITS_PER_WORD; }
98 static _GLIBCXX_CONSTEXPR size_t
99 _S_whichbyte(size_t __pos) _GLIBCXX_NOEXCEPT
100 { return (__pos % _GLIBCXX_BITSET_BITS_PER_WORD) / __CHAR_BIT__; }
102 static _GLIBCXX_CONSTEXPR size_t
103 _S_whichbit(size_t __pos) _GLIBCXX_NOEXCEPT
104 { return __pos % _GLIBCXX_BITSET_BITS_PER_WORD; }
106 static _GLIBCXX_CONSTEXPR _WordT
107 _S_maskbit(size_t __pos) _GLIBCXX_NOEXCEPT
108 { return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
110 _WordT&
111 _M_getword(size_t __pos) _GLIBCXX_NOEXCEPT
112 { return _M_w[_S_whichword(__pos)]; }
114 _GLIBCXX_CONSTEXPR _WordT
115 _M_getword(size_t __pos) const _GLIBCXX_NOEXCEPT
116 { return _M_w[_S_whichword(__pos)]; }
118 #if __cplusplus >= 201103L
119 const _WordT*
120 _M_getdata() const noexcept
121 { return _M_w; }
122 #endif
124 _WordT&
125 _M_hiword() _GLIBCXX_NOEXCEPT
126 { return _M_w[_Nw - 1]; }
128 _GLIBCXX_CONSTEXPR _WordT
129 _M_hiword() const _GLIBCXX_NOEXCEPT
130 { return _M_w[_Nw - 1]; }
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 }
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 }
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 }
153 void
154 _M_do_left_shift(size_t __shift) _GLIBCXX_NOEXCEPT;
156 void
157 _M_do_right_shift(size_t __shift) _GLIBCXX_NOEXCEPT;
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 }
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 }
173 void
174 _M_do_reset() _GLIBCXX_NOEXCEPT
175 { __builtin_memset(_M_w, 0, _Nw * sizeof(_WordT)); }
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 }
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 }
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 }
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 }
216 unsigned long
217 _M_do_to_ulong() const;
219 #if __cplusplus >= 201103L
220 unsigned long long
221 _M_do_to_ullong() const;
222 #endif
224 // find first "on" bit
225 size_t
226 _M_do_find_first(size_t) const _GLIBCXX_NOEXCEPT;
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 };
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;
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 }
256 std::fill(_M_w + 0, _M_w + __wshift, static_cast<_WordT>(0));
257 }
258 }
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;
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 }
283 std::fill(_M_w + __limit + 1, _M_w + _Nw, static_cast<_WordT>(0));
284 }
285 }
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 }
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"));
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
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 }
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;
338 // check out of bounds
339 if (__prev >= _Nw * _GLIBCXX_BITSET_BITS_PER_WORD)
340 return __not_found;
342 // search first word
343 size_t __i = _S_whichword(__prev);
344 _WordT __thisword = _M_w[__i];
346 // mask off bits below bound
347 __thisword &= (~static_cast<_WordT>(0)) << _S_whichbit(__prev);
349 if (__thisword != static_cast<_WordT>(0))
350 return (__i * _GLIBCXX_BITSET_BITS_PER_WORD
351 + __builtin_ctzl(__thisword));
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
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;
377 _GLIBCXX_CONSTEXPR _Base_bitset() _GLIBCXX_NOEXCEPT
378 : _M_w(0)
379 { }
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 { }
389 static _GLIBCXX_CONSTEXPR size_t
390 _S_whichword(size_t __pos) _GLIBCXX_NOEXCEPT
391 { return __pos / _GLIBCXX_BITSET_BITS_PER_WORD; }
393 static _GLIBCXX_CONSTEXPR size_t
394 _S_whichbyte(size_t __pos) _GLIBCXX_NOEXCEPT
395 { return (__pos % _GLIBCXX_BITSET_BITS_PER_WORD) / __CHAR_BIT__; }
397 static _GLIBCXX_CONSTEXPR size_t
398 _S_whichbit(size_t __pos) _GLIBCXX_NOEXCEPT
399 { return __pos % _GLIBCXX_BITSET_BITS_PER_WORD; }
401 static _GLIBCXX_CONSTEXPR _WordT
402 _S_maskbit(size_t __pos) _GLIBCXX_NOEXCEPT
403 { return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
405 _WordT&
406 _M_getword(size_t) _GLIBCXX_NOEXCEPT
407 { return _M_w; }
409 _GLIBCXX_CONSTEXPR _WordT
410 _M_getword(size_t) const _GLIBCXX_NOEXCEPT
411 { return _M_w; }
413 #if __cplusplus >= 201103L
414 const _WordT*
415 _M_getdata() const noexcept
416 { return &_M_w; }
417 #endif
419 _WordT&
420 _M_hiword() _GLIBCXX_NOEXCEPT
421 { return _M_w; }
423 _GLIBCXX_CONSTEXPR _WordT
424 _M_hiword() const _GLIBCXX_NOEXCEPT
425 { return _M_w; }
427 void
428 _M_do_and(const _Base_bitset<1>& __x) _GLIBCXX_NOEXCEPT
429 { _M_w &= __x._M_w; }
431 void
432 _M_do_or(const _Base_bitset<1>& __x) _GLIBCXX_NOEXCEPT
433 { _M_w |= __x._M_w; }
435 void
436 _M_do_xor(const _Base_bitset<1>& __x) _GLIBCXX_NOEXCEPT
437 { _M_w ^= __x._M_w; }
439 void
440 _M_do_left_shift(size_t __shift) _GLIBCXX_NOEXCEPT
441 { _M_w <<= __shift; }
443 void
444 _M_do_right_shift(size_t __shift) _GLIBCXX_NOEXCEPT
445 { _M_w >>= __shift; }
447 void
448 _M_do_flip() _GLIBCXX_NOEXCEPT
449 { _M_w = ~_M_w; }
451 void
452 _M_do_set() _GLIBCXX_NOEXCEPT
453 { _M_w = ~static_cast<_WordT>(0); }
455 void
456 _M_do_reset() _GLIBCXX_NOEXCEPT
457 { _M_w = 0; }
459 bool
460 _M_is_equal(const _Base_bitset<1>& __x) const _GLIBCXX_NOEXCEPT
461 { return _M_w == __x._M_w; }
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)); }
469 bool
470 _M_is_any() const _GLIBCXX_NOEXCEPT
471 { return _M_w != 0; }
473 size_t
474 _M_do_count() const _GLIBCXX_NOEXCEPT
475 { return __builtin_popcountl(_M_w); }
477 unsigned long
478 _M_do_to_ulong() const _GLIBCXX_NOEXCEPT
479 { return _M_w; }
481 #if __cplusplus >= 201103L
482 unsigned long long
483 _M_do_to_ullong() const noexcept
484 { return _M_w; }
485 #endif
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 }
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;
505 _WordT __x = _M_w >> __prev;
506 if (__x != 0)
507 return __builtin_ctzl(__x) + __prev;
508 else
509 return __not_found;
510 }
511 };
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;
523 _GLIBCXX_CONSTEXPR _Base_bitset() _GLIBCXX_NOEXCEPT
524 { }
526 #if __cplusplus >= 201103L
527 constexpr _Base_bitset(unsigned long long) noexcept
528 #else
529 _Base_bitset(unsigned long)
530 #endif
531 { }
533 static _GLIBCXX_CONSTEXPR size_t
534 _S_whichword(size_t __pos) _GLIBCXX_NOEXCEPT
535 { return __pos / _GLIBCXX_BITSET_BITS_PER_WORD; }
537 static _GLIBCXX_CONSTEXPR size_t
538 _S_whichbyte(size_t __pos) _GLIBCXX_NOEXCEPT
539 { return (__pos % _GLIBCXX_BITSET_BITS_PER_WORD) / __CHAR_BIT__; }
541 static _GLIBCXX_CONSTEXPR size_t
542 _S_whichbit(size_t __pos) _GLIBCXX_NOEXCEPT
543 { return __pos % _GLIBCXX_BITSET_BITS_PER_WORD; }
545 static _GLIBCXX_CONSTEXPR _WordT
546 _S_maskbit(size_t __pos) _GLIBCXX_NOEXCEPT
547 { return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
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 }
563 _GLIBCXX_CONSTEXPR _WordT
564 _M_getword(size_t __pos) const _GLIBCXX_NOEXCEPT
565 { return 0; }
567 _GLIBCXX_CONSTEXPR _WordT
568 _M_hiword() const _GLIBCXX_NOEXCEPT
569 { return 0; }
571 void
572 _M_do_and(const _Base_bitset<0>&) _GLIBCXX_NOEXCEPT
573 { }
575 void
576 _M_do_or(const _Base_bitset<0>&) _GLIBCXX_NOEXCEPT
577 { }
579 void
580 _M_do_xor(const _Base_bitset<0>&) _GLIBCXX_NOEXCEPT
581 { }
583 void
584 _M_do_left_shift(size_t) _GLIBCXX_NOEXCEPT
585 { }
587 void
588 _M_do_right_shift(size_t) _GLIBCXX_NOEXCEPT
589 { }
591 void
592 _M_do_flip() _GLIBCXX_NOEXCEPT
593 { }
595 void
596 _M_do_set() _GLIBCXX_NOEXCEPT
597 { }
599 void
600 _M_do_reset() _GLIBCXX_NOEXCEPT
601 { }
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; }
610 template<size_t _Nb>
611 bool
612 _M_are_all() const _GLIBCXX_NOEXCEPT
613 { return true; }
615 bool
616 _M_is_any() const _GLIBCXX_NOEXCEPT
617 { return false; }
619 size_t
620 _M_do_count() const _GLIBCXX_NOEXCEPT
621 { return 0; }
623 unsigned long
624 _M_do_to_ulong() const _GLIBCXX_NOEXCEPT
625 { return 0; }
627 #if __cplusplus >= 201103L
628 unsigned long long
629 _M_do_to_ullong() const noexcept
630 { return 0; }
631 #endif
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; }
639 size_t
640 _M_do_find_next(size_t, size_t) const _GLIBCXX_NOEXCEPT
641 { return 0; }
642 };
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;
651 static void
652 _S_do_sanitize(_WordT& __val) _GLIBCXX_NOEXCEPT
653 { __val &= ~((~static_cast<_WordT>(0)) << _Extrabits); }
654 };
656 template<>
657 struct _Sanitize<0>
658 {
659 typedef unsigned long _WordT;
661 static void
662 _S_do_sanitize(_WordT) _GLIBCXX_NOEXCEPT { }
663 };
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 };
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
683 /**
684 * @class bitset <bitset>
685 *
686 * @brief The %bitset class represents a @e fixed-size sequence of bits.
687 * @ingroup utilities
688 *
689 * (Note that %bitset does @e not meet the formal requirements of a
690 * <a href="tables.html#65">container</a>. Mainly, it lacks iterators.)
691 *
692 * The template argument, @a Nb, may be any non-negative number,
693 * specifying the number of bits (e.g., "0", "12", "1024*1024").
694 *
695 * In the general unoptimized case, storage is allocated in word-sized
696 * blocks. Let B be the number of bits in a word, then (Nb+(B-1))/B
697 * words will be used for storage. B - Nb%B bits are unused. (They are
698 * the high-order bits in the highest word.) It is a class invariant
699 * that those unused bits are always zero.
700 *
701 * If you think of %bitset as <em>a simple array of bits</em>, be
702 * aware that your mental picture is reversed: a %bitset behaves
703 * the same way as bits in integers do, with the bit at index 0 in
704 * the <em>least significant / right-hand</em> position, and the bit at
705 * index Nb-1 in the <em>most significant / left-hand</em> position.
706 * Thus, unlike other containers, a %bitset's index <em>counts from
707 * right to left</em>, to put it very loosely.
708 *
709 * This behavior is preserved when translating to and from strings. For
710 * example, the first line of the following program probably prints
711 * <em>b('a') is 0001100001</em> on a modern ASCII system.
712 *
713 * @code
714 * #include <bitset>
715 * #include <iostream>
716 * #include <sstream>
717 *
718 * using namespace std;
719 *
720 * int main()
721 * {
722 * long a = 'a';
723 * bitset<10> b(a);
724 *
725 * cout << "b('a') is " << b << endl;
726 *
727 * ostringstream s;
728 * s << b;
729 * string str = s.str();
730 * cout << "index 3 in the string is " << str[3] << " but\n"
731 * << "index 3 in the bitset is " << b[3] << endl;
732 * }
733 * @endcode
734 *
735 * Also see:
736 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/ext_containers.html
737 * for a description of extensions.
738 *
739 * Most of the actual code isn't contained in %bitset<> itself, but in the
740 * base class _Base_bitset. The base class works with whole words, not with
741 * individual bits. This allows us to specialize _Base_bitset for the
742 * important special case where the %bitset is only a single word.
743 *
744 * Extra confusion can result due to the fact that the storage for
745 * _Base_bitset @e is a regular array, and is indexed as such. This is
746 * carefully encapsulated.
747 */
748 template<size_t _Nb>
749 class bitset
750 : private _Base_bitset<_GLIBCXX_BITSET_WORDS(_Nb)>
751 {
752 private:
753 typedef _Base_bitset<_GLIBCXX_BITSET_WORDS(_Nb)> _Base;
754 typedef unsigned long _WordT;
756 template<class _CharT, class _Traits, class _Alloc>
757 void
758 _M_check_initial_position(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
759 size_t __position) const
760 {
761 if (__position > __s.size())
762 __throw_out_of_range_fmt(__N("bitset::bitset: __position "
763 "(which is %zu) > __s.size() "
764 "(which is %zu)"),
765 __position, __s.size());
766 }
768 void _M_check(size_t __position, const char *__s) const
769 {
770 if (__position >= _Nb)
771 __throw_out_of_range_fmt(__N("%s: __position (which is %zu) "
772 ">= _Nb (which is %zu)"),
773 __s, __position, _Nb);
774 }
776 void
777 _M_do_sanitize() _GLIBCXX_NOEXCEPT
778 {
779 typedef _Sanitize<_Nb % _GLIBCXX_BITSET_BITS_PER_WORD> __sanitize_type;
780 __sanitize_type::_S_do_sanitize(this->_M_hiword());
781 }
783 #if __cplusplus >= 201103L
784 template<typename> friend struct hash;
785 #endif
787 public:
788 /**
789 * This encapsulates the concept of a single bit. An instance of this
790 * class is a proxy for an actual bit; this way the individual bit
791 * operations are done as faster word-size bitwise instructions.
792 *
793 * Most users will never need to use this class directly; conversions
794 * to and from bool are automatic and should be transparent. Overloaded
795 * operators help to preserve the illusion.
796 *
797 * (On a typical system, this <em>bit %reference</em> is 64
798 * times the size of an actual bit. Ha.)
799 */
800 class reference
801 {
802 friend class bitset;
804 _WordT* _M_wp;
805 size_t _M_bpos;
807 // left undefined
808 reference();
810 public:
811 reference(bitset& __b, size_t __pos) _GLIBCXX_NOEXCEPT
812 {
813 _M_wp = &__b._M_getword(__pos);
814 _M_bpos = _Base::_S_whichbit(__pos);
815 }
817 ~reference() _GLIBCXX_NOEXCEPT
818 { }
820 // For b[i] = __x;
821 reference&
822 operator=(bool __x) _GLIBCXX_NOEXCEPT
823 {
824 if (__x)
825 *_M_wp |= _Base::_S_maskbit(_M_bpos);
826 else
827 *_M_wp &= ~_Base::_S_maskbit(_M_bpos);
828 return *this;
829 }
831 // For b[i] = b[__j];
832 reference&
833 operator=(const reference& __j) _GLIBCXX_NOEXCEPT
834 {
835 if ((*(__j._M_wp) & _Base::_S_maskbit(__j._M_bpos)))
836 *_M_wp |= _Base::_S_maskbit(_M_bpos);
837 else
838 *_M_wp &= ~_Base::_S_maskbit(_M_bpos);
839 return *this;
840 }
842 // Flips the bit
843 bool
844 operator~() const _GLIBCXX_NOEXCEPT
845 { return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) == 0; }
847 // For __x = b[i];
848 operator bool() const _GLIBCXX_NOEXCEPT
849 { return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) != 0; }
851 // For b[i].flip();
852 reference&
853 flip() _GLIBCXX_NOEXCEPT
854 {
855 *_M_wp ^= _Base::_S_maskbit(_M_bpos);
856 return *this;
857 }
858 };
859 friend class reference;
861 // 23.3.5.1 constructors:
862 /// All bits set to zero.
863 _GLIBCXX_CONSTEXPR bitset() _GLIBCXX_NOEXCEPT
864 { }
866 /// Initial bits bitwise-copied from a single word (others set to zero).
867 #if __cplusplus >= 201103L
868 constexpr bitset(unsigned long long __val) noexcept
869 : _Base(_Sanitize_val<_Nb>::_S_do_sanitize_val(__val)) { }
870 #else
871 bitset(unsigned long __val)
872 : _Base(__val)
873 { _M_do_sanitize(); }
874 #endif
876 /**
877 * Use a subset of a string.
878 * @param __s A string of @a 0 and @a 1 characters.
879 * @param __position Index of the first character in @a __s to use;
880 * defaults to zero.
881 * @throw std::out_of_range If @a pos is bigger the size of @a __s.
882 * @throw std::invalid_argument If a character appears in the string
883 * which is neither @a 0 nor @a 1.
884 */
885 template<class _CharT, class _Traits, class _Alloc>
886 explicit
887 bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
888 size_t __position = 0)
889 : _Base()
890 {
891 _M_check_initial_position(__s, __position);
892 _M_copy_from_string(__s, __position,
893 std::basic_string<_CharT, _Traits, _Alloc>::npos,
894 _CharT('0'), _CharT('1'));
895 }
897 /**
898 * Use a subset of a string.
899 * @param __s A string of @a 0 and @a 1 characters.
900 * @param __position Index of the first character in @a __s to use.
901 * @param __n The number of characters to copy.
902 * @throw std::out_of_range If @a __position is bigger the size
903 * of @a __s.
904 * @throw std::invalid_argument If a character appears in the string
905 * which is neither @a 0 nor @a 1.
906 */
907 template<class _CharT, class _Traits, class _Alloc>
908 bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
909 size_t __position, size_t __n)
910 : _Base()
911 {
912 _M_check_initial_position(__s, __position);
913 _M_copy_from_string(__s, __position, __n, _CharT('0'), _CharT('1'));
914 }
916 // _GLIBCXX_RESOLVE_LIB_DEFECTS
917 // 396. what are characters zero and one.
918 template<class _CharT, class _Traits, class _Alloc>
919 bitset(const std::basic_string<_CharT, _Traits, _Alloc>& __s,
920 size_t __position, size_t __n,
921 _CharT __zero, _CharT __one = _CharT('1'))
922 : _Base()
923 {
924 _M_check_initial_position(__s, __position);
925 _M_copy_from_string(__s, __position, __n, __zero, __one);
926 }
928 #if __cplusplus >= 201103L
929 /**
930 * Construct from a character %array.
931 * @param __str An %array of characters @a zero and @a one.
932 * @param __n The number of characters to use.
933 * @param __zero The character corresponding to the value 0.
934 * @param __one The character corresponding to the value 1.
935 * @throw std::invalid_argument If a character appears in the string
936 * which is neither @a __zero nor @a __one.
937 */
938 template<typename _CharT>
939 explicit
940 bitset(const _CharT* __str,
941 typename std::basic_string<_CharT>::size_type __n
942 = std::basic_string<_CharT>::npos,
943 _CharT __zero = _CharT('0'), _CharT __one = _CharT('1'))
944 : _Base()
945 {
946 if (!__str)
947 __throw_logic_error(__N("bitset::bitset(const _CharT*, ...)"));
949 if (__n == std::basic_string<_CharT>::npos)
950 __n = std::char_traits<_CharT>::length(__str);
951 _M_copy_from_ptr<_CharT, std::char_traits<_CharT>>(__str, __n, 0,
952 __n, __zero,
953 __one);
954 }
955 #endif
957 // 23.3.5.2 bitset operations:
958 //@{
959 /**
960 * Operations on bitsets.
961 * @param __rhs A same-sized bitset.
962 *
963 * These should be self-explanatory.
964 */
965 bitset<_Nb>&
966 operator&=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
967 {
968 this->_M_do_and(__rhs);
969 return *this;
970 }
972 bitset<_Nb>&
973 operator|=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
974 {
975 this->_M_do_or(__rhs);
976 return *this;
977 }
979 bitset<_Nb>&
980 operator^=(const bitset<_Nb>& __rhs) _GLIBCXX_NOEXCEPT
981 {
982 this->_M_do_xor(__rhs);
983 return *this;
984 }
985 //@}
987 //@{
988 /**
989 * Operations on bitsets.
990 * @param __position The number of places to shift.
991 *
992 * These should be self-explanatory.
993 */
994 bitset<_Nb>&
995 operator<<=(size_t __position) _GLIBCXX_NOEXCEPT
996 {
997 if (__builtin_expect(__position < _Nb, 1))
998 {
999 this->_M_do_left_shift(__position);
1000 this->_M_do_sanitize();
1001 }
1002 else
1003 this->_M_do_reset();
1004 return *this;
1005 }
1007 bitset<_Nb>&
1008 operator>>=(size_t __position) _GLIBCXX_NOEXCEPT
1009 {
1010 if (__builtin_expect(__position < _Nb, 1))
1011 {
1012 this->_M_do_right_shift(__position);
1013 this->_M_do_sanitize();
1014 }
1015 else
1016 this->_M_do_reset();
1017 return *this;
1018 }
1019 //@}
1021 //@{
1022 /**
1023 * These versions of single-bit set, reset, flip, and test are
1024 * extensions from the SGI version. They do no range checking.
1025 * @ingroup SGIextensions
1026 */
1027 bitset<_Nb>&
1028 _Unchecked_set(size_t __pos) _GLIBCXX_NOEXCEPT
1029 {
1030 this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
1031 return *this;
1032 }
1034 bitset<_Nb>&
1035 _Unchecked_set(size_t __pos, int __val) _GLIBCXX_NOEXCEPT
1036 {
1037 if (__val)
1038 this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
1039 else
1040 this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
1041 return *this;
1042 }
1044 bitset<_Nb>&
1045 _Unchecked_reset(size_t __pos) _GLIBCXX_NOEXCEPT
1046 {
1047 this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
1048 return *this;
1049 }
1051 bitset<_Nb>&
1052 _Unchecked_flip(size_t __pos) _GLIBCXX_NOEXCEPT
1053 {
1054 this->_M_getword(__pos) ^= _Base::_S_maskbit(__pos);
1055 return *this;
1056 }
1058 _GLIBCXX_CONSTEXPR bool
1059 _Unchecked_test(size_t __pos) const _GLIBCXX_NOEXCEPT
1060 { return ((this->_M_getword(__pos) & _Base::_S_maskbit(__pos))
1061 != static_cast<_WordT>(0)); }
1062 //@}
1064 // Set, reset, and flip.
1065 /**
1066 * @brief Sets every bit to true.
1067 */
1068 bitset<_Nb>&
1069 set() _GLIBCXX_NOEXCEPT
1070 {
1071 this->_M_do_set();
1072 this->_M_do_sanitize();
1073 return *this;
1074 }
1076 /**
1077 * @brief Sets a given bit to a particular value.
1078 * @param __position The index of the bit.
1079 * @param __val Either true or false, defaults to true.
1080 * @throw std::out_of_range If @a pos is bigger the size of the %set.
1081 */
1082 bitset<_Nb>&
1083 set(size_t __position, bool __val = true)
1084 {
1085 this->_M_check(__position, __N("bitset::set"));
1086 return _Unchecked_set(__position, __val);
1087 }
1089 /**
1090 * @brief Sets every bit to false.
1091 */
1092 bitset<_Nb>&
1093 reset() _GLIBCXX_NOEXCEPT
1094 {
1095 this->_M_do_reset();
1096 return *this;
1097 }
1099 /**
1100 * @brief Sets a given bit to false.
1101 * @param __position The index of the bit.
1102 * @throw std::out_of_range If @a pos is bigger the size of the %set.
1103 *
1104 * Same as writing @c set(pos,false).
1105 */
1106 bitset<_Nb>&
1107 reset(size_t __position)
1108 {
1109 this->_M_check(__position, __N("bitset::reset"));
1110 return _Unchecked_reset(__position);
1111 }
1113 /**
1114 * @brief Toggles every bit to its opposite value.
1115 */
1116 bitset<_Nb>&
1117 flip() _GLIBCXX_NOEXCEPT
1118 {
1119 this->_M_do_flip();
1120 this->_M_do_sanitize();
1121 return *this;
1122 }
1124 /**
1125 * @brief Toggles a given bit to its opposite value.
1126 * @param __position The index of the bit.
1127 * @throw std::out_of_range If @a pos is bigger the size of the %set.
1128 */
1129 bitset<_Nb>&
1130 flip(size_t __position)
1131 {
1132 this->_M_check(__position, __N("bitset::flip"));
1133 return _Unchecked_flip(__position);
1134 }
1136 /// See the no-argument flip().
1137 bitset<_Nb>
1138 operator~() const _GLIBCXX_NOEXCEPT
1139 { return bitset<_Nb>(*this).flip(); }
1141 //@{
1142 /**
1143 * @brief Array-indexing support.
1144 * @param __position Index into the %bitset.
1145 * @return A bool for a <em>const %bitset</em>. For non-const
1146 * bitsets, an instance of the reference proxy class.
1147 * @note These operators do no range checking and throw no exceptions,
1148 * as required by DR 11 to the standard.
1149 *
1150 * _GLIBCXX_RESOLVE_LIB_DEFECTS Note that this implementation already
1151 * resolves DR 11 (items 1 and 2), but does not do the range-checking
1152 * required by that DR's resolution. -pme
1153 * The DR has since been changed: range-checking is a precondition
1154 * (users' responsibility), and these functions must not throw. -pme
1155 */
1156 reference
1157 operator[](size_t __position)
1158 { return reference(*this, __position); }
1160 _GLIBCXX_CONSTEXPR bool
1161 operator[](size_t __position) const
1162 { return _Unchecked_test(__position); }
1163 //@}
1165 /**
1166 * @brief Returns a numerical interpretation of the %bitset.
1167 * @return The integral equivalent of the bits.
1168 * @throw std::overflow_error If there are too many bits to be
1169 * represented in an @c unsigned @c long.
1170 */
1171 unsigned long
1172 to_ulong() const
1173 { return this->_M_do_to_ulong(); }
1175 #if __cplusplus >= 201103L
1176 unsigned long long
1177 to_ullong() const
1178 { return this->_M_do_to_ullong(); }
1179 #endif
1181 /**
1182 * @brief Returns a character interpretation of the %bitset.
1183 * @return The string equivalent of the bits.
1184 *
1185 * Note the ordering of the bits: decreasing character positions
1186 * correspond to increasing bit positions (see the main class notes for
1187 * an example).
1188 */
1189 template<class _CharT, class _Traits, class _Alloc>
1190 std::basic_string<_CharT, _Traits, _Alloc>
1191 to_string() const
1192 {
1193 std::basic_string<_CharT, _Traits, _Alloc> __result;
1194 _M_copy_to_string(__result, _CharT('0'), _CharT('1'));
1195 return __result;
1196 }
1198 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1199 // 396. what are characters zero and one.
1200 template<class _CharT, class _Traits, class _Alloc>
1201 std::basic_string<_CharT, _Traits, _Alloc>
1202 to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1203 {
1204 std::basic_string<_CharT, _Traits, _Alloc> __result;
1205 _M_copy_to_string(__result, __zero, __one);
1206 return __result;
1207 }
1209 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1210 // 434. bitset::to_string() hard to use.
1211 template<class _CharT, class _Traits>
1212 std::basic_string<_CharT, _Traits, std::allocator<_CharT> >
1213 to_string() const
1214 { return to_string<_CharT, _Traits, std::allocator<_CharT> >(); }
1216 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1217 // 853. to_string needs updating with zero and one.
1218 template<class _CharT, class _Traits>
1219 std::basic_string<_CharT, _Traits, std::allocator<_CharT> >
1220 to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1221 { return to_string<_CharT, _Traits,
1222 std::allocator<_CharT> >(__zero, __one); }
1224 template<class _CharT>
1225 std::basic_string<_CharT, std::char_traits<_CharT>,
1226 std::allocator<_CharT> >
1227 to_string() const
1228 {
1229 return to_string<_CharT, std::char_traits<_CharT>,
1230 std::allocator<_CharT> >();
1231 }
1233 template<class _CharT>
1234 std::basic_string<_CharT, std::char_traits<_CharT>,
1235 std::allocator<_CharT> >
1236 to_string(_CharT __zero, _CharT __one = _CharT('1')) const
1237 {
1238 return to_string<_CharT, std::char_traits<_CharT>,
1239 std::allocator<_CharT> >(__zero, __one);
1240 }
1242 std::basic_string<char, std::char_traits<char>, std::allocator<char> >
1243 to_string() const
1244 {
1245 return to_string<char, std::char_traits<char>,
1246 std::allocator<char> >();
1247 }
1249 std::basic_string<char, std::char_traits<char>, std::allocator<char> >
1250 to_string(char __zero, char __one = '1') const
1251 {
1252 return to_string<char, std::char_traits<char>,
1253 std::allocator<char> >(__zero, __one);
1254 }
1256 // Helper functions for string operations.
1257 template<class _CharT, class _Traits>
1258 void
1259 _M_copy_from_ptr(const _CharT*, size_t, size_t, size_t,
1260 _CharT, _CharT);
1262 template<class _CharT, class _Traits, class _Alloc>
1263 void
1264 _M_copy_from_string(const std::basic_string<_CharT,
1265 _Traits, _Alloc>& __s, size_t __pos, size_t __n,
1266 _CharT __zero, _CharT __one)
1267 { _M_copy_from_ptr<_CharT, _Traits>(__s.data(), __s.size(), __pos, __n,
1268 __zero, __one); }
1270 template<class _CharT, class _Traits, class _Alloc>
1271 void
1272 _M_copy_to_string(std::basic_string<_CharT, _Traits, _Alloc>&,
1273 _CharT, _CharT) const;
1275 // NB: Backward compat.
1276 template<class _CharT, class _Traits, class _Alloc>
1277 void
1278 _M_copy_from_string(const std::basic_string<_CharT,
1279 _Traits, _Alloc>& __s, size_t __pos, size_t __n)
1280 { _M_copy_from_string(__s, __pos, __n, _CharT('0'), _CharT('1')); }
1282 template<class _CharT, class _Traits, class _Alloc>
1283 void
1284 _M_copy_to_string(std::basic_string<_CharT, _Traits,_Alloc>& __s) const
1285 { _M_copy_to_string(__s, _CharT('0'), _CharT('1')); }
1287 /// Returns the number of bits which are set.
1288 size_t
1289 count() const _GLIBCXX_NOEXCEPT
1290 { return this->_M_do_count(); }
1292 /// Returns the total number of bits.
1293 _GLIBCXX_CONSTEXPR size_t
1294 size() const _GLIBCXX_NOEXCEPT
1295 { return _Nb; }
1297 //@{
1298 /// These comparisons for equality/inequality are, well, @e bitwise.
1299 bool
1300 operator==(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
1301 { return this->_M_is_equal(__rhs); }
1303 bool
1304 operator!=(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
1305 { return !this->_M_is_equal(__rhs); }
1306 //@}
1308 /**
1309 * @brief Tests the value of a bit.
1310 * @param __position The index of a bit.
1311 * @return The value at @a pos.
1312 * @throw std::out_of_range If @a pos is bigger the size of the %set.
1313 */
1314 bool
1315 test(size_t __position) const
1316 {
1317 this->_M_check(__position, __N("bitset::test"));
1318 return _Unchecked_test(__position);
1319 }
1321 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1322 // DR 693. std::bitset::all() missing.
1323 /**
1324 * @brief Tests whether all the bits are on.
1325 * @return True if all the bits are set.
1326 */
1327 bool
1328 all() const _GLIBCXX_NOEXCEPT
1329 { return this->template _M_are_all<_Nb>(); }
1331 /**
1332 * @brief Tests whether any of the bits are on.
1333 * @return True if at least one bit is set.
1334 */
1335 bool
1336 any() const _GLIBCXX_NOEXCEPT
1337 { return this->_M_is_any(); }
1339 /**
1340 * @brief Tests whether any of the bits are on.
1341 * @return True if none of the bits are set.
1342 */
1343 bool
1344 none() const _GLIBCXX_NOEXCEPT
1345 { return !this->_M_is_any(); }
1347 //@{
1348 /// Self-explanatory.
1349 bitset<_Nb>
1350 operator<<(size_t __position) const _GLIBCXX_NOEXCEPT
1351 { return bitset<_Nb>(*this) <<= __position; }
1353 bitset<_Nb>
1354 operator>>(size_t __position) const _GLIBCXX_NOEXCEPT
1355 { return bitset<_Nb>(*this) >>= __position; }
1356 //@}
1358 /**
1359 * @brief Finds the index of the first "on" bit.
1360 * @return The index of the first bit set, or size() if not found.
1361 * @ingroup SGIextensions
1362 * @sa _Find_next
1363 */
1364 size_t
1365 _Find_first() const _GLIBCXX_NOEXCEPT
1366 { return this->_M_do_find_first(_Nb); }
1368 /**
1369 * @brief Finds the index of the next "on" bit after prev.
1370 * @return The index of the next bit set, or size() if not found.
1371 * @param __prev Where to start searching.
1372 * @ingroup SGIextensions
1373 * @sa _Find_first
1374 */
1375 size_t
1376 _Find_next(size_t __prev) const _GLIBCXX_NOEXCEPT
1377 { return this->_M_do_find_next(__prev, _Nb); }
1378 };
1380 // Definitions of non-inline member functions.
1381 template<size_t _Nb>
1382 template<class _CharT, class _Traits>
1383 void
1384 bitset<_Nb>::
1385 _M_copy_from_ptr(const _CharT* __s, size_t __len,
1386 size_t __pos, size_t __n, _CharT __zero, _CharT __one)
1387 {
1388 reset();
1389 const size_t __nbits = std::min(_Nb, std::min(__n, size_t(__len - __pos)));
1390 for (size_t __i = __nbits; __i > 0; --__i)
1391 {
1392 const _CharT __c = __s[__pos + __nbits - __i];
1393 if (_Traits::eq(__c, __zero))
1394 ;
1395 else if (_Traits::eq(__c, __one))
1396 _Unchecked_set(__i - 1);
1397 else
1398 __throw_invalid_argument(__N("bitset::_M_copy_from_ptr"));
1399 }
1400 }
1402 template<size_t _Nb>
1403 template<class _CharT, class _Traits, class _Alloc>
1404 void
1405 bitset<_Nb>::
1406 _M_copy_to_string(std::basic_string<_CharT, _Traits, _Alloc>& __s,
1407 _CharT __zero, _CharT __one) const
1408 {
1409 __s.assign(_Nb, __zero);
1410 for (size_t __i = _Nb; __i > 0; --__i)
1411 if (_Unchecked_test(__i - 1))
1412 _Traits::assign(__s[_Nb - __i], __one);
1413 }
1415 // 23.3.5.3 bitset operations:
1416 //@{
1417 /**
1418 * @brief Global bitwise operations on bitsets.
1419 * @param __x A bitset.
1420 * @param __y A bitset of the same size as @a __x.
1421 * @return A new bitset.
1422 *
1423 * These should be self-explanatory.
1424 */
1425 template<size_t _Nb>
1426 inline bitset<_Nb>
1427 operator&(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1428 {
1429 bitset<_Nb> __result(__x);
1430 __result &= __y;
1431 return __result;
1432 }
1434 template<size_t _Nb>
1435 inline bitset<_Nb>
1436 operator|(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1437 {
1438 bitset<_Nb> __result(__x);
1439 __result |= __y;
1440 return __result;
1441 }
1443 template <size_t _Nb>
1444 inline bitset<_Nb>
1445 operator^(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
1446 {
1447 bitset<_Nb> __result(__x);
1448 __result ^= __y;
1449 return __result;
1450 }
1451 //@}
1453 //@{
1454 /**
1455 * @brief Global I/O operators for bitsets.
1456 *
1457 * Direct I/O between streams and bitsets is supported. Output is
1458 * straightforward. Input will skip whitespace, only accept @a 0 and @a 1
1459 * characters, and will only extract as many digits as the %bitset will
1460 * hold.
1461 */
1462 template<class _CharT, class _Traits, size_t _Nb>
1463 std::basic_istream<_CharT, _Traits>&
1464 operator>>(std::basic_istream<_CharT, _Traits>& __is, bitset<_Nb>& __x)
1465 {
1466 typedef typename _Traits::char_type char_type;
1467 typedef std::basic_istream<_CharT, _Traits> __istream_type;
1468 typedef typename __istream_type::ios_base __ios_base;
1470 std::basic_string<_CharT, _Traits> __tmp;
1471 __tmp.reserve(_Nb);
1473 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1474 // 303. Bitset input operator underspecified
1475 const char_type __zero = __is.widen('0');
1476 const char_type __one = __is.widen('1');
1478 typename __ios_base::iostate __state = __ios_base::goodbit;
1479 typename __istream_type::sentry __sentry(__is);
1480 if (__sentry)
1481 {
1482 __try
1483 {
1484 for (size_t __i = _Nb; __i > 0; --__i)
1485 {
1486 static typename _Traits::int_type __eof = _Traits::eof();
1488 typename _Traits::int_type __c1 = __is.rdbuf()->sbumpc();
1489 if (_Traits::eq_int_type(__c1, __eof))
1490 {
1491 __state |= __ios_base::eofbit;
1492 break;
1493 }
1494 else
1495 {
1496 const char_type __c2 = _Traits::to_char_type(__c1);
1497 if (_Traits::eq(__c2, __zero))
1498 __tmp.push_back(__zero);
1499 else if (_Traits::eq(__c2, __one))
1500 __tmp.push_back(__one);
1501 else if (_Traits::
1502 eq_int_type(__is.rdbuf()->sputbackc(__c2),
1503 __eof))
1504 {
1505 __state |= __ios_base::failbit;
1506 break;
1507 }
1508 }
1509 }
1510 }
1511 __catch(__cxxabiv1::__forced_unwind&)
1512 {
1513 __is._M_setstate(__ios_base::badbit);
1514 __throw_exception_again;
1515 }
1516 __catch(...)
1517 { __is._M_setstate(__ios_base::badbit); }
1518 }
1520 if (__tmp.empty() && _Nb)
1521 __state |= __ios_base::failbit;
1522 else
1523 __x._M_copy_from_string(__tmp, static_cast<size_t>(0), _Nb,
1524 __zero, __one);
1525 if (__state)
1526 __is.setstate(__state);
1527 return __is;
1528 }
1530 template <class _CharT, class _Traits, size_t _Nb>
1531 std::basic_ostream<_CharT, _Traits>&
1532 operator<<(std::basic_ostream<_CharT, _Traits>& __os,
1533 const bitset<_Nb>& __x)
1534 {
1535 std::basic_string<_CharT, _Traits> __tmp;
1537 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1538 // 396. what are characters zero and one.
1539 const ctype<_CharT>& __ct = use_facet<ctype<_CharT> >(__os.getloc());
1540 __x._M_copy_to_string(__tmp, __ct.widen('0'), __ct.widen('1'));
1541 return __os << __tmp;
1542 }
1543 //@}
1545 _GLIBCXX_END_NAMESPACE_CONTAINER
1546 } // namespace std
1548 #undef _GLIBCXX_BITSET_WORDS
1549 #undef _GLIBCXX_BITSET_BITS_PER_WORD
1550 #undef _GLIBCXX_BITSET_BITS_PER_ULL
1552 #if __cplusplus >= 201103L
1554 #include <bits/functional_hash.h>
1556 namespace std _GLIBCXX_VISIBILITY(default)
1557 {
1558 _GLIBCXX_BEGIN_NAMESPACE_VERSION
1560 // DR 1182.
1561 /// std::hash specialization for bitset.
1562 template<size_t _Nb>
1563 struct hash<_GLIBCXX_STD_C::bitset<_Nb>>
1564 : public __hash_base<size_t, _GLIBCXX_STD_C::bitset<_Nb>>
1565 {
1566 size_t
1567 operator()(const _GLIBCXX_STD_C::bitset<_Nb>& __b) const noexcept
1568 {
1569 const size_t __clength = (_Nb + __CHAR_BIT__ - 1) / __CHAR_BIT__;
1570 return std::_Hash_impl::hash(__b._M_getdata(), __clength);
1571 }
1572 };
1574 template<>
1575 struct hash<_GLIBCXX_STD_C::bitset<0>>
1576 : public __hash_base<size_t, _GLIBCXX_STD_C::bitset<0>>
1577 {
1578 size_t
1579 operator()(const _GLIBCXX_STD_C::bitset<0>&) const noexcept
1580 { return 0; }
1581 };
1583 _GLIBCXX_END_NAMESPACE_VERSION
1584 } // namespace
1586 #endif // C++11
1588 #ifdef _GLIBCXX_DEBUG
1589 # include <debug/bitset>
1590 #endif
1592 #ifdef _GLIBCXX_PROFILE
1593 # include <profile/bitset>
1594 #endif
1596 #endif /* _GLIBCXX_BITSET */