libstdc++
stl_algobase.h
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1 // Core algorithmic facilities -*- C++ -*-
2 
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25 /*
26  *
27  * Copyright (c) 1994
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42  * Permission to use, copy, modify, distribute and sell this software
43  * and its documentation for any purpose is hereby granted without fee,
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49  */
50 
51 /** @file bits/stl_algobase.h
52  * This is an internal header file, included by other library headers.
53  * Do not attempt to use it directly. @headername{algorithm}
54  */
55 
56 #ifndef _STL_ALGOBASE_H
57 #define _STL_ALGOBASE_H 1
58 
59 #include <bits/c++config.h>
60 #include <bits/functexcept.h>
61 #include <bits/cpp_type_traits.h>
62 #include <ext/type_traits.h>
63 #include <ext/numeric_traits.h>
64 #include <bits/stl_pair.h>
65 #include <bits/stl_iterator_base_types.h>
66 #include <bits/stl_iterator_base_funcs.h>
67 #include <bits/stl_iterator.h>
68 #include <bits/concept_check.h>
69 #include <debug/debug.h>
70 #include <bits/move.h> // For std::swap and _GLIBCXX_MOVE
71 #include <bits/predefined_ops.h>
72 
73 namespace std _GLIBCXX_VISIBILITY(default)
74 {
75 _GLIBCXX_BEGIN_NAMESPACE_VERSION
76 
77 #if __cplusplus < 201103L
78  // See http://gcc.gnu.org/ml/libstdc++/2004-08/msg00167.html: in a
79  // nutshell, we are partially implementing the resolution of DR 187,
80  // when it's safe, i.e., the value_types are equal.
81  template<bool _BoolType>
82  struct __iter_swap
83  {
84  template<typename _ForwardIterator1, typename _ForwardIterator2>
85  static void
86  iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
87  {
88  typedef typename iterator_traits<_ForwardIterator1>::value_type
89  _ValueType1;
90  _ValueType1 __tmp = _GLIBCXX_MOVE(*__a);
91  *__a = _GLIBCXX_MOVE(*__b);
92  *__b = _GLIBCXX_MOVE(__tmp);
93  }
94  };
95 
96  template<>
97  struct __iter_swap<true>
98  {
99  template<typename _ForwardIterator1, typename _ForwardIterator2>
100  static void
101  iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
102  {
103  swap(*__a, *__b);
104  }
105  };
106 #endif
107 
108  /**
109  * @brief Swaps the contents of two iterators.
110  * @ingroup mutating_algorithms
111  * @param __a An iterator.
112  * @param __b Another iterator.
113  * @return Nothing.
114  *
115  * This function swaps the values pointed to by two iterators, not the
116  * iterators themselves.
117  */
118  template<typename _ForwardIterator1, typename _ForwardIterator2>
119  inline void
120  iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
121  {
122  // concept requirements
123  __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
124  _ForwardIterator1>)
125  __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
126  _ForwardIterator2>)
127 
128 #if __cplusplus < 201103L
129  typedef typename iterator_traits<_ForwardIterator1>::value_type
130  _ValueType1;
131  typedef typename iterator_traits<_ForwardIterator2>::value_type
132  _ValueType2;
133 
134  __glibcxx_function_requires(_ConvertibleConcept<_ValueType1,
135  _ValueType2>)
136  __glibcxx_function_requires(_ConvertibleConcept<_ValueType2,
137  _ValueType1>)
138 
139  typedef typename iterator_traits<_ForwardIterator1>::reference
140  _ReferenceType1;
141  typedef typename iterator_traits<_ForwardIterator2>::reference
142  _ReferenceType2;
143  std::__iter_swap<__are_same<_ValueType1, _ValueType2>::__value
144  && __are_same<_ValueType1&, _ReferenceType1>::__value
145  && __are_same<_ValueType2&, _ReferenceType2>::__value>::
146  iter_swap(__a, __b);
147 #else
148  swap(*__a, *__b);
149 #endif
150  }
151 
152  /**
153  * @brief Swap the elements of two sequences.
154  * @ingroup mutating_algorithms
155  * @param __first1 A forward iterator.
156  * @param __last1 A forward iterator.
157  * @param __first2 A forward iterator.
158  * @return An iterator equal to @p first2+(last1-first1).
159  *
160  * Swaps each element in the range @p [first1,last1) with the
161  * corresponding element in the range @p [first2,(last1-first1)).
162  * The ranges must not overlap.
163  */
164  template<typename _ForwardIterator1, typename _ForwardIterator2>
165  _ForwardIterator2
166  swap_ranges(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
167  _ForwardIterator2 __first2)
168  {
169  // concept requirements
170  __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
171  _ForwardIterator1>)
172  __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
173  _ForwardIterator2>)
174  __glibcxx_requires_valid_range(__first1, __last1);
175 
176  for (; __first1 != __last1; ++__first1, ++__first2)
177  std::iter_swap(__first1, __first2);
178  return __first2;
179  }
180 
181  /**
182  * @brief This does what you think it does.
183  * @ingroup sorting_algorithms
184  * @param __a A thing of arbitrary type.
185  * @param __b Another thing of arbitrary type.
186  * @return The lesser of the parameters.
187  *
188  * This is the simple classic generic implementation. It will work on
189  * temporary expressions, since they are only evaluated once, unlike a
190  * preprocessor macro.
191  */
192  template<typename _Tp>
193  _GLIBCXX14_CONSTEXPR
194  inline const _Tp&
195  min(const _Tp& __a, const _Tp& __b)
196  {
197  // concept requirements
198  __glibcxx_function_requires(_LessThanComparableConcept<_Tp>)
199  //return __b < __a ? __b : __a;
200  if (__b < __a)
201  return __b;
202  return __a;
203  }
204 
205  /**
206  * @brief This does what you think it does.
207  * @ingroup sorting_algorithms
208  * @param __a A thing of arbitrary type.
209  * @param __b Another thing of arbitrary type.
210  * @return The greater of the parameters.
211  *
212  * This is the simple classic generic implementation. It will work on
213  * temporary expressions, since they are only evaluated once, unlike a
214  * preprocessor macro.
215  */
216  template<typename _Tp>
217  _GLIBCXX14_CONSTEXPR
218  inline const _Tp&
219  max(const _Tp& __a, const _Tp& __b)
220  {
221  // concept requirements
222  __glibcxx_function_requires(_LessThanComparableConcept<_Tp>)
223  //return __a < __b ? __b : __a;
224  if (__a < __b)
225  return __b;
226  return __a;
227  }
228 
229  /**
230  * @brief This does what you think it does.
231  * @ingroup sorting_algorithms
232  * @param __a A thing of arbitrary type.
233  * @param __b Another thing of arbitrary type.
234  * @param __comp A @link comparison_functors comparison functor@endlink.
235  * @return The lesser of the parameters.
236  *
237  * This will work on temporary expressions, since they are only evaluated
238  * once, unlike a preprocessor macro.
239  */
240  template<typename _Tp, typename _Compare>
241  _GLIBCXX14_CONSTEXPR
242  inline const _Tp&
243  min(const _Tp& __a, const _Tp& __b, _Compare __comp)
244  {
245  //return __comp(__b, __a) ? __b : __a;
246  if (__comp(__b, __a))
247  return __b;
248  return __a;
249  }
250 
251  /**
252  * @brief This does what you think it does.
253  * @ingroup sorting_algorithms
254  * @param __a A thing of arbitrary type.
255  * @param __b Another thing of arbitrary type.
256  * @param __comp A @link comparison_functors comparison functor@endlink.
257  * @return The greater of the parameters.
258  *
259  * This will work on temporary expressions, since they are only evaluated
260  * once, unlike a preprocessor macro.
261  */
262  template<typename _Tp, typename _Compare>
263  _GLIBCXX14_CONSTEXPR
264  inline const _Tp&
265  max(const _Tp& __a, const _Tp& __b, _Compare __comp)
266  {
267  //return __comp(__a, __b) ? __b : __a;
268  if (__comp(__a, __b))
269  return __b;
270  return __a;
271  }
272 
273  // If _Iterator is a __normal_iterator return its base (a plain pointer,
274  // normally) otherwise return it untouched. See copy, fill, ...
275  template<typename _Iterator>
276  struct _Niter_base
277  : _Iter_base<_Iterator, __is_normal_iterator<_Iterator>::__value>
278  { };
279 
280  template<typename _Iterator>
281  inline typename _Niter_base<_Iterator>::iterator_type
282  __niter_base(_Iterator __it)
283  { return std::_Niter_base<_Iterator>::_S_base(__it); }
284 
285  // Likewise, for move_iterator.
286  template<typename _Iterator>
287  struct _Miter_base
288  : _Iter_base<_Iterator, __is_move_iterator<_Iterator>::__value>
289  { };
290 
291  template<typename _Iterator>
292  inline typename _Miter_base<_Iterator>::iterator_type
293  __miter_base(_Iterator __it)
294  { return std::_Miter_base<_Iterator>::_S_base(__it); }
295 
296  // All of these auxiliary structs serve two purposes. (1) Replace
297  // calls to copy with memmove whenever possible. (Memmove, not memcpy,
298  // because the input and output ranges are permitted to overlap.)
299  // (2) If we're using random access iterators, then write the loop as
300  // a for loop with an explicit count.
301 
302  template<bool, bool, typename>
303  struct __copy_move
304  {
305  template<typename _II, typename _OI>
306  static _OI
307  __copy_m(_II __first, _II __last, _OI __result)
308  {
309  for (; __first != __last; ++__result, ++__first)
310  *__result = *__first;
311  return __result;
312  }
313  };
314 
315 #if __cplusplus >= 201103L
316  template<typename _Category>
317  struct __copy_move<true, false, _Category>
318  {
319  template<typename _II, typename _OI>
320  static _OI
321  __copy_m(_II __first, _II __last, _OI __result)
322  {
323  for (; __first != __last; ++__result, ++__first)
324  *__result = std::move(*__first);
325  return __result;
326  }
327  };
328 #endif
329 
330  template<>
331  struct __copy_move<false, false, random_access_iterator_tag>
332  {
333  template<typename _II, typename _OI>
334  static _OI
335  __copy_m(_II __first, _II __last, _OI __result)
336  {
337  typedef typename iterator_traits<_II>::difference_type _Distance;
338  for(_Distance __n = __last - __first; __n > 0; --__n)
339  {
340  *__result = *__first;
341  ++__first;
342  ++__result;
343  }
344  return __result;
345  }
346  };
347 
348 #if __cplusplus >= 201103L
349  template<>
350  struct __copy_move<true, false, random_access_iterator_tag>
351  {
352  template<typename _II, typename _OI>
353  static _OI
354  __copy_m(_II __first, _II __last, _OI __result)
355  {
356  typedef typename iterator_traits<_II>::difference_type _Distance;
357  for(_Distance __n = __last - __first; __n > 0; --__n)
358  {
359  *__result = std::move(*__first);
360  ++__first;
361  ++__result;
362  }
363  return __result;
364  }
365  };
366 #endif
367 
368  template<bool _IsMove>
369  struct __copy_move<_IsMove, true, random_access_iterator_tag>
370  {
371  template<typename _Tp>
372  static _Tp*
373  __copy_m(const _Tp* __first, const _Tp* __last, _Tp* __result)
374  {
375 #if __cplusplus >= 201103L
376  using __assignable = conditional<_IsMove,
377  is_move_assignable<_Tp>,
378  is_copy_assignable<_Tp>>;
379  // trivial types can have deleted assignment
380  static_assert( __assignable::type::value, "type is not assignable" );
381 #endif
382  const ptrdiff_t _Num = __last - __first;
383  if (_Num)
384  __builtin_memmove(__result, __first, sizeof(_Tp) * _Num);
385  return __result + _Num;
386  }
387  };
388 
389  template<bool _IsMove, typename _II, typename _OI>
390  inline _OI
391  __copy_move_a(_II __first, _II __last, _OI __result)
392  {
393  typedef typename iterator_traits<_II>::value_type _ValueTypeI;
394  typedef typename iterator_traits<_OI>::value_type _ValueTypeO;
395  typedef typename iterator_traits<_II>::iterator_category _Category;
396  const bool __simple = (__is_trivial(_ValueTypeI)
397  && __is_pointer<_II>::__value
398  && __is_pointer<_OI>::__value
399  && __are_same<_ValueTypeI, _ValueTypeO>::__value);
400 
401  return std::__copy_move<_IsMove, __simple,
402  _Category>::__copy_m(__first, __last, __result);
403  }
404 
405  // Helpers for streambuf iterators (either istream or ostream).
406  // NB: avoid including <iosfwd>, relatively large.
407  template<typename _CharT>
408  struct char_traits;
409 
410  template<typename _CharT, typename _Traits>
411  class istreambuf_iterator;
412 
413  template<typename _CharT, typename _Traits>
414  class ostreambuf_iterator;
415 
416  template<bool _IsMove, typename _CharT>
417  typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
418  ostreambuf_iterator<_CharT, char_traits<_CharT> > >::__type
419  __copy_move_a2(_CharT*, _CharT*,
420  ostreambuf_iterator<_CharT, char_traits<_CharT> >);
421 
422  template<bool _IsMove, typename _CharT>
423  typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
424  ostreambuf_iterator<_CharT, char_traits<_CharT> > >::__type
425  __copy_move_a2(const _CharT*, const _CharT*,
426  ostreambuf_iterator<_CharT, char_traits<_CharT> >);
427 
428  template<bool _IsMove, typename _CharT>
429  typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
430  _CharT*>::__type
431  __copy_move_a2(istreambuf_iterator<_CharT, char_traits<_CharT> >,
432  istreambuf_iterator<_CharT, char_traits<_CharT> >, _CharT*);
433 
434  template<bool _IsMove, typename _II, typename _OI>
435  inline _OI
436  __copy_move_a2(_II __first, _II __last, _OI __result)
437  {
438  return _OI(std::__copy_move_a<_IsMove>(std::__niter_base(__first),
439  std::__niter_base(__last),
440  std::__niter_base(__result)));
441  }
442 
443  /**
444  * @brief Copies the range [first,last) into result.
445  * @ingroup mutating_algorithms
446  * @param __first An input iterator.
447  * @param __last An input iterator.
448  * @param __result An output iterator.
449  * @return result + (first - last)
450  *
451  * This inline function will boil down to a call to @c memmove whenever
452  * possible. Failing that, if random access iterators are passed, then the
453  * loop count will be known (and therefore a candidate for compiler
454  * optimizations such as unrolling). Result may not be contained within
455  * [first,last); the copy_backward function should be used instead.
456  *
457  * Note that the end of the output range is permitted to be contained
458  * within [first,last).
459  */
460  template<typename _II, typename _OI>
461  inline _OI
462  copy(_II __first, _II __last, _OI __result)
463  {
464  // concept requirements
465  __glibcxx_function_requires(_InputIteratorConcept<_II>)
466  __glibcxx_function_requires(_OutputIteratorConcept<_OI,
467  typename iterator_traits<_II>::value_type>)
468  __glibcxx_requires_valid_range(__first, __last);
469 
470  return (std::__copy_move_a2<__is_move_iterator<_II>::__value>
471  (std::__miter_base(__first), std::__miter_base(__last),
472  __result));
473  }
474 
475 #if __cplusplus >= 201103L
476  /**
477  * @brief Moves the range [first,last) into result.
478  * @ingroup mutating_algorithms
479  * @param __first An input iterator.
480  * @param __last An input iterator.
481  * @param __result An output iterator.
482  * @return result + (first - last)
483  *
484  * This inline function will boil down to a call to @c memmove whenever
485  * possible. Failing that, if random access iterators are passed, then the
486  * loop count will be known (and therefore a candidate for compiler
487  * optimizations such as unrolling). Result may not be contained within
488  * [first,last); the move_backward function should be used instead.
489  *
490  * Note that the end of the output range is permitted to be contained
491  * within [first,last).
492  */
493  template<typename _II, typename _OI>
494  inline _OI
495  move(_II __first, _II __last, _OI __result)
496  {
497  // concept requirements
498  __glibcxx_function_requires(_InputIteratorConcept<_II>)
499  __glibcxx_function_requires(_OutputIteratorConcept<_OI,
500  typename iterator_traits<_II>::value_type>)
501  __glibcxx_requires_valid_range(__first, __last);
502 
503  return std::__copy_move_a2<true>(std::__miter_base(__first),
504  std::__miter_base(__last), __result);
505  }
506 
507 #define _GLIBCXX_MOVE3(_Tp, _Up, _Vp) std::move(_Tp, _Up, _Vp)
508 #else
509 #define _GLIBCXX_MOVE3(_Tp, _Up, _Vp) std::copy(_Tp, _Up, _Vp)
510 #endif
511 
512  template<bool, bool, typename>
513  struct __copy_move_backward
514  {
515  template<typename _BI1, typename _BI2>
516  static _BI2
517  __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result)
518  {
519  while (__first != __last)
520  *--__result = *--__last;
521  return __result;
522  }
523  };
524 
525 #if __cplusplus >= 201103L
526  template<typename _Category>
527  struct __copy_move_backward<true, false, _Category>
528  {
529  template<typename _BI1, typename _BI2>
530  static _BI2
531  __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result)
532  {
533  while (__first != __last)
534  *--__result = std::move(*--__last);
535  return __result;
536  }
537  };
538 #endif
539 
540  template<>
541  struct __copy_move_backward<false, false, random_access_iterator_tag>
542  {
543  template<typename _BI1, typename _BI2>
544  static _BI2
545  __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result)
546  {
547  typename iterator_traits<_BI1>::difference_type __n;
548  for (__n = __last - __first; __n > 0; --__n)
549  *--__result = *--__last;
550  return __result;
551  }
552  };
553 
554 #if __cplusplus >= 201103L
555  template<>
556  struct __copy_move_backward<true, false, random_access_iterator_tag>
557  {
558  template<typename _BI1, typename _BI2>
559  static _BI2
560  __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result)
561  {
562  typename iterator_traits<_BI1>::difference_type __n;
563  for (__n = __last - __first; __n > 0; --__n)
564  *--__result = std::move(*--__last);
565  return __result;
566  }
567  };
568 #endif
569 
570  template<bool _IsMove>
571  struct __copy_move_backward<_IsMove, true, random_access_iterator_tag>
572  {
573  template<typename _Tp>
574  static _Tp*
575  __copy_move_b(const _Tp* __first, const _Tp* __last, _Tp* __result)
576  {
577 #if __cplusplus >= 201103L
578  using __assignable = conditional<_IsMove,
579  is_move_assignable<_Tp>,
580  is_copy_assignable<_Tp>>;
581  // trivial types can have deleted assignment
582  static_assert( __assignable::type::value, "type is not assignable" );
583 #endif
584  const ptrdiff_t _Num = __last - __first;
585  if (_Num)
586  __builtin_memmove(__result - _Num, __first, sizeof(_Tp) * _Num);
587  return __result - _Num;
588  }
589  };
590 
591  template<bool _IsMove, typename _BI1, typename _BI2>
592  inline _BI2
593  __copy_move_backward_a(_BI1 __first, _BI1 __last, _BI2 __result)
594  {
595  typedef typename iterator_traits<_BI1>::value_type _ValueType1;
596  typedef typename iterator_traits<_BI2>::value_type _ValueType2;
597  typedef typename iterator_traits<_BI1>::iterator_category _Category;
598  const bool __simple = (__is_trivial(_ValueType1)
599  && __is_pointer<_BI1>::__value
600  && __is_pointer<_BI2>::__value
601  && __are_same<_ValueType1, _ValueType2>::__value);
602 
603  return std::__copy_move_backward<_IsMove, __simple,
604  _Category>::__copy_move_b(__first,
605  __last,
606  __result);
607  }
608 
609  template<bool _IsMove, typename _BI1, typename _BI2>
610  inline _BI2
611  __copy_move_backward_a2(_BI1 __first, _BI1 __last, _BI2 __result)
612  {
613  return _BI2(std::__copy_move_backward_a<_IsMove>
614  (std::__niter_base(__first), std::__niter_base(__last),
615  std::__niter_base(__result)));
616  }
617 
618  /**
619  * @brief Copies the range [first,last) into result.
620  * @ingroup mutating_algorithms
621  * @param __first A bidirectional iterator.
622  * @param __last A bidirectional iterator.
623  * @param __result A bidirectional iterator.
624  * @return result - (first - last)
625  *
626  * The function has the same effect as copy, but starts at the end of the
627  * range and works its way to the start, returning the start of the result.
628  * This inline function will boil down to a call to @c memmove whenever
629  * possible. Failing that, if random access iterators are passed, then the
630  * loop count will be known (and therefore a candidate for compiler
631  * optimizations such as unrolling).
632  *
633  * Result may not be in the range (first,last]. Use copy instead. Note
634  * that the start of the output range may overlap [first,last).
635  */
636  template<typename _BI1, typename _BI2>
637  inline _BI2
638  copy_backward(_BI1 __first, _BI1 __last, _BI2 __result)
639  {
640  // concept requirements
641  __glibcxx_function_requires(_BidirectionalIteratorConcept<_BI1>)
642  __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<_BI2>)
643  __glibcxx_function_requires(_ConvertibleConcept<
644  typename iterator_traits<_BI1>::value_type,
645  typename iterator_traits<_BI2>::value_type>)
646  __glibcxx_requires_valid_range(__first, __last);
647 
648  return (std::__copy_move_backward_a2<__is_move_iterator<_BI1>::__value>
649  (std::__miter_base(__first), std::__miter_base(__last),
650  __result));
651  }
652 
653 #if __cplusplus >= 201103L
654  /**
655  * @brief Moves the range [first,last) into result.
656  * @ingroup mutating_algorithms
657  * @param __first A bidirectional iterator.
658  * @param __last A bidirectional iterator.
659  * @param __result A bidirectional iterator.
660  * @return result - (first - last)
661  *
662  * The function has the same effect as move, but starts at the end of the
663  * range and works its way to the start, returning the start of the result.
664  * This inline function will boil down to a call to @c memmove whenever
665  * possible. Failing that, if random access iterators are passed, then the
666  * loop count will be known (and therefore a candidate for compiler
667  * optimizations such as unrolling).
668  *
669  * Result may not be in the range (first,last]. Use move instead. Note
670  * that the start of the output range may overlap [first,last).
671  */
672  template<typename _BI1, typename _BI2>
673  inline _BI2
674  move_backward(_BI1 __first, _BI1 __last, _BI2 __result)
675  {
676  // concept requirements
677  __glibcxx_function_requires(_BidirectionalIteratorConcept<_BI1>)
678  __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<_BI2>)
679  __glibcxx_function_requires(_ConvertibleConcept<
680  typename iterator_traits<_BI1>::value_type,
681  typename iterator_traits<_BI2>::value_type>)
682  __glibcxx_requires_valid_range(__first, __last);
683 
684  return std::__copy_move_backward_a2<true>(std::__miter_base(__first),
685  std::__miter_base(__last),
686  __result);
687  }
688 
689 #define _GLIBCXX_MOVE_BACKWARD3(_Tp, _Up, _Vp) std::move_backward(_Tp, _Up, _Vp)
690 #else
691 #define _GLIBCXX_MOVE_BACKWARD3(_Tp, _Up, _Vp) std::copy_backward(_Tp, _Up, _Vp)
692 #endif
693 
694  template<typename _ForwardIterator, typename _Tp>
695  inline typename
696  __gnu_cxx::__enable_if<!__is_scalar<_Tp>::__value, void>::__type
697  __fill_a(_ForwardIterator __first, _ForwardIterator __last,
698  const _Tp& __value)
699  {
700  for (; __first != __last; ++__first)
701  *__first = __value;
702  }
703 
704  template<typename _ForwardIterator, typename _Tp>
705  inline typename
706  __gnu_cxx::__enable_if<__is_scalar<_Tp>::__value, void>::__type
707  __fill_a(_ForwardIterator __first, _ForwardIterator __last,
708  const _Tp& __value)
709  {
710  const _Tp __tmp = __value;
711  for (; __first != __last; ++__first)
712  *__first = __tmp;
713  }
714 
715  // Specialization: for char types we can use memset.
716  template<typename _Tp>
717  inline typename
718  __gnu_cxx::__enable_if<__is_byte<_Tp>::__value, void>::__type
719  __fill_a(_Tp* __first, _Tp* __last, const _Tp& __c)
720  {
721  const _Tp __tmp = __c;
722  if (const size_t __len = __last - __first)
723  __builtin_memset(__first, static_cast<unsigned char>(__tmp), __len);
724  }
725 
726  /**
727  * @brief Fills the range [first,last) with copies of value.
728  * @ingroup mutating_algorithms
729  * @param __first A forward iterator.
730  * @param __last A forward iterator.
731  * @param __value A reference-to-const of arbitrary type.
732  * @return Nothing.
733  *
734  * This function fills a range with copies of the same value. For char
735  * types filling contiguous areas of memory, this becomes an inline call
736  * to @c memset or @c wmemset.
737  */
738  template<typename _ForwardIterator, typename _Tp>
739  inline void
740  fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value)
741  {
742  // concept requirements
743  __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
744  _ForwardIterator>)
745  __glibcxx_requires_valid_range(__first, __last);
746 
747  std::__fill_a(std::__niter_base(__first), std::__niter_base(__last),
748  __value);
749  }
750 
751  template<typename _OutputIterator, typename _Size, typename _Tp>
752  inline typename
753  __gnu_cxx::__enable_if<!__is_scalar<_Tp>::__value, _OutputIterator>::__type
754  __fill_n_a(_OutputIterator __first, _Size __n, const _Tp& __value)
755  {
756  for (__decltype(__n + 0) __niter = __n;
757  __niter > 0; --__niter, ++__first)
758  *__first = __value;
759  return __first;
760  }
761 
762  template<typename _OutputIterator, typename _Size, typename _Tp>
763  inline typename
764  __gnu_cxx::__enable_if<__is_scalar<_Tp>::__value, _OutputIterator>::__type
765  __fill_n_a(_OutputIterator __first, _Size __n, const _Tp& __value)
766  {
767  const _Tp __tmp = __value;
768  for (__decltype(__n + 0) __niter = __n;
769  __niter > 0; --__niter, ++__first)
770  *__first = __tmp;
771  return __first;
772  }
773 
774  template<typename _Size, typename _Tp>
775  inline typename
776  __gnu_cxx::__enable_if<__is_byte<_Tp>::__value, _Tp*>::__type
777  __fill_n_a(_Tp* __first, _Size __n, const _Tp& __c)
778  {
779  std::__fill_a(__first, __first + __n, __c);
780  return __first + __n;
781  }
782 
783  /**
784  * @brief Fills the range [first,first+n) with copies of value.
785  * @ingroup mutating_algorithms
786  * @param __first An output iterator.
787  * @param __n The count of copies to perform.
788  * @param __value A reference-to-const of arbitrary type.
789  * @return The iterator at first+n.
790  *
791  * This function fills a range with copies of the same value. For char
792  * types filling contiguous areas of memory, this becomes an inline call
793  * to @c memset or @ wmemset.
794  *
795  * _GLIBCXX_RESOLVE_LIB_DEFECTS
796  * DR 865. More algorithms that throw away information
797  */
798  template<typename _OI, typename _Size, typename _Tp>
799  inline _OI
800  fill_n(_OI __first, _Size __n, const _Tp& __value)
801  {
802  // concept requirements
803  __glibcxx_function_requires(_OutputIteratorConcept<_OI, _Tp>)
804 
805  return _OI(std::__fill_n_a(std::__niter_base(__first), __n, __value));
806  }
807 
808  template<bool _BoolType>
809  struct __equal
810  {
811  template<typename _II1, typename _II2>
812  static bool
813  equal(_II1 __first1, _II1 __last1, _II2 __first2)
814  {
815  for (; __first1 != __last1; ++__first1, ++__first2)
816  if (!(*__first1 == *__first2))
817  return false;
818  return true;
819  }
820  };
821 
822  template<>
823  struct __equal<true>
824  {
825  template<typename _Tp>
826  static bool
827  equal(const _Tp* __first1, const _Tp* __last1, const _Tp* __first2)
828  {
829  if (const size_t __len = (__last1 - __first1))
830  return !__builtin_memcmp(__first1, __first2, sizeof(_Tp) * __len);
831  return true;
832  }
833  };
834 
835  template<typename _II1, typename _II2>
836  inline bool
837  __equal_aux(_II1 __first1, _II1 __last1, _II2 __first2)
838  {
839  typedef typename iterator_traits<_II1>::value_type _ValueType1;
840  typedef typename iterator_traits<_II2>::value_type _ValueType2;
841  const bool __simple = ((__is_integer<_ValueType1>::__value
842  || __is_pointer<_ValueType1>::__value)
843  && __is_pointer<_II1>::__value
844  && __is_pointer<_II2>::__value
845  && __are_same<_ValueType1, _ValueType2>::__value);
846 
847  return std::__equal<__simple>::equal(__first1, __last1, __first2);
848  }
849 
850  template<typename, typename>
851  struct __lc_rai
852  {
853  template<typename _II1, typename _II2>
854  static _II1
855  __newlast1(_II1, _II1 __last1, _II2, _II2)
856  { return __last1; }
857 
858  template<typename _II>
859  static bool
860  __cnd2(_II __first, _II __last)
861  { return __first != __last; }
862  };
863 
864  template<>
865  struct __lc_rai<random_access_iterator_tag, random_access_iterator_tag>
866  {
867  template<typename _RAI1, typename _RAI2>
868  static _RAI1
869  __newlast1(_RAI1 __first1, _RAI1 __last1,
870  _RAI2 __first2, _RAI2 __last2)
871  {
872  const typename iterator_traits<_RAI1>::difference_type
873  __diff1 = __last1 - __first1;
874  const typename iterator_traits<_RAI2>::difference_type
875  __diff2 = __last2 - __first2;
876  return __diff2 < __diff1 ? __first1 + __diff2 : __last1;
877  }
878 
879  template<typename _RAI>
880  static bool
881  __cnd2(_RAI, _RAI)
882  { return true; }
883  };
884 
885  template<typename _II1, typename _II2, typename _Compare>
886  bool
887  __lexicographical_compare_impl(_II1 __first1, _II1 __last1,
888  _II2 __first2, _II2 __last2,
889  _Compare __comp)
890  {
891  typedef typename iterator_traits<_II1>::iterator_category _Category1;
892  typedef typename iterator_traits<_II2>::iterator_category _Category2;
893  typedef std::__lc_rai<_Category1, _Category2> __rai_type;
894 
895  __last1 = __rai_type::__newlast1(__first1, __last1, __first2, __last2);
896  for (; __first1 != __last1 && __rai_type::__cnd2(__first2, __last2);
897  ++__first1, ++__first2)
898  {
899  if (__comp(__first1, __first2))
900  return true;
901  if (__comp(__first2, __first1))
902  return false;
903  }
904  return __first1 == __last1 && __first2 != __last2;
905  }
906 
907  template<bool _BoolType>
908  struct __lexicographical_compare
909  {
910  template<typename _II1, typename _II2>
911  static bool __lc(_II1, _II1, _II2, _II2);
912  };
913 
914  template<bool _BoolType>
915  template<typename _II1, typename _II2>
916  bool
917  __lexicographical_compare<_BoolType>::
918  __lc(_II1 __first1, _II1 __last1, _II2 __first2, _II2 __last2)
919  {
920  return std::__lexicographical_compare_impl(__first1, __last1,
921  __first2, __last2,
922  __gnu_cxx::__ops::__iter_less_iter());
923  }
924 
925  template<>
926  struct __lexicographical_compare<true>
927  {
928  template<typename _Tp, typename _Up>
929  static bool
930  __lc(const _Tp* __first1, const _Tp* __last1,
931  const _Up* __first2, const _Up* __last2)
932  {
933  const size_t __len1 = __last1 - __first1;
934  const size_t __len2 = __last2 - __first2;
935  if (const size_t __len = std::min(__len1, __len2))
936  if (int __result = __builtin_memcmp(__first1, __first2, __len))
937  return __result < 0;
938  return __len1 < __len2;
939  }
940  };
941 
942  template<typename _II1, typename _II2>
943  inline bool
944  __lexicographical_compare_aux(_II1 __first1, _II1 __last1,
945  _II2 __first2, _II2 __last2)
946  {
947  typedef typename iterator_traits<_II1>::value_type _ValueType1;
948  typedef typename iterator_traits<_II2>::value_type _ValueType2;
949  const bool __simple =
950  (__is_byte<_ValueType1>::__value && __is_byte<_ValueType2>::__value
951  && !__gnu_cxx::__numeric_traits<_ValueType1>::__is_signed
952  && !__gnu_cxx::__numeric_traits<_ValueType2>::__is_signed
953  && __is_pointer<_II1>::__value
954  && __is_pointer<_II2>::__value);
955 
956  return std::__lexicographical_compare<__simple>::__lc(__first1, __last1,
957  __first2, __last2);
958  }
959 
960  template<typename _ForwardIterator, typename _Tp, typename _Compare>
961  _ForwardIterator
962  __lower_bound(_ForwardIterator __first, _ForwardIterator __last,
963  const _Tp& __val, _Compare __comp)
964  {
965  typedef typename iterator_traits<_ForwardIterator>::difference_type
966  _DistanceType;
967 
968  _DistanceType __len = std::distance(__first, __last);
969 
970  while (__len > 0)
971  {
972  _DistanceType __half = __len >> 1;
973  _ForwardIterator __middle = __first;
974  std::advance(__middle, __half);
975  if (__comp(__middle, __val))
976  {
977  __first = __middle;
978  ++__first;
979  __len = __len - __half - 1;
980  }
981  else
982  __len = __half;
983  }
984  return __first;
985  }
986 
987  /**
988  * @brief Finds the first position in which @a val could be inserted
989  * without changing the ordering.
990  * @param __first An iterator.
991  * @param __last Another iterator.
992  * @param __val The search term.
993  * @return An iterator pointing to the first element <em>not less
994  * than</em> @a val, or end() if every element is less than
995  * @a val.
996  * @ingroup binary_search_algorithms
997  */
998  template<typename _ForwardIterator, typename _Tp>
999  inline _ForwardIterator
1000  lower_bound(_ForwardIterator __first, _ForwardIterator __last,
1001  const _Tp& __val)
1002  {
1003  // concept requirements
1004  __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1005  __glibcxx_function_requires(_LessThanOpConcept<
1006  typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
1007  __glibcxx_requires_partitioned_lower(__first, __last, __val);
1008 
1009  return std::__lower_bound(__first, __last, __val,
1010  __gnu_cxx::__ops::__iter_less_val());
1011  }
1012 
1013  /// This is a helper function for the sort routines and for random.tcc.
1014  // Precondition: __n > 0.
1015  inline _GLIBCXX_CONSTEXPR int
1016  __lg(int __n)
1017  { return sizeof(int) * __CHAR_BIT__ - 1 - __builtin_clz(__n); }
1018 
1019  inline _GLIBCXX_CONSTEXPR unsigned
1020  __lg(unsigned __n)
1021  { return sizeof(int) * __CHAR_BIT__ - 1 - __builtin_clz(__n); }
1022 
1023  inline _GLIBCXX_CONSTEXPR long
1024  __lg(long __n)
1025  { return sizeof(long) * __CHAR_BIT__ - 1 - __builtin_clzl(__n); }
1026 
1027  inline _GLIBCXX_CONSTEXPR unsigned long
1028  __lg(unsigned long __n)
1029  { return sizeof(long) * __CHAR_BIT__ - 1 - __builtin_clzl(__n); }
1030 
1031  inline _GLIBCXX_CONSTEXPR long long
1032  __lg(long long __n)
1033  { return sizeof(long long) * __CHAR_BIT__ - 1 - __builtin_clzll(__n); }
1034 
1035  inline _GLIBCXX_CONSTEXPR unsigned long long
1036  __lg(unsigned long long __n)
1037  { return sizeof(long long) * __CHAR_BIT__ - 1 - __builtin_clzll(__n); }
1038 
1039 _GLIBCXX_END_NAMESPACE_VERSION
1040 
1041 _GLIBCXX_BEGIN_NAMESPACE_ALGO
1042 
1043  /**
1044  * @brief Tests a range for element-wise equality.
1045  * @ingroup non_mutating_algorithms
1046  * @param __first1 An input iterator.
1047  * @param __last1 An input iterator.
1048  * @param __first2 An input iterator.
1049  * @return A boolean true or false.
1050  *
1051  * This compares the elements of two ranges using @c == and returns true or
1052  * false depending on whether all of the corresponding elements of the
1053  * ranges are equal.
1054  */
1055  template<typename _II1, typename _II2>
1056  inline bool
1057  equal(_II1 __first1, _II1 __last1, _II2 __first2)
1058  {
1059  // concept requirements
1060  __glibcxx_function_requires(_InputIteratorConcept<_II1>)
1061  __glibcxx_function_requires(_InputIteratorConcept<_II2>)
1062  __glibcxx_function_requires(_EqualOpConcept<
1063  typename iterator_traits<_II1>::value_type,
1064  typename iterator_traits<_II2>::value_type>)
1065  __glibcxx_requires_valid_range(__first1, __last1);
1066 
1067  return std::__equal_aux(std::__niter_base(__first1),
1068  std::__niter_base(__last1),
1069  std::__niter_base(__first2));
1070  }
1071 
1072  /**
1073  * @brief Tests a range for element-wise equality.
1074  * @ingroup non_mutating_algorithms
1075  * @param __first1 An input iterator.
1076  * @param __last1 An input iterator.
1077  * @param __first2 An input iterator.
1078  * @param __binary_pred A binary predicate @link functors
1079  * functor@endlink.
1080  * @return A boolean true or false.
1081  *
1082  * This compares the elements of two ranges using the binary_pred
1083  * parameter, and returns true or
1084  * false depending on whether all of the corresponding elements of the
1085  * ranges are equal.
1086  */
1087  template<typename _IIter1, typename _IIter2, typename _BinaryPredicate>
1088  inline bool
1089  equal(_IIter1 __first1, _IIter1 __last1,
1090  _IIter2 __first2, _BinaryPredicate __binary_pred)
1091  {
1092  // concept requirements
1093  __glibcxx_function_requires(_InputIteratorConcept<_IIter1>)
1094  __glibcxx_function_requires(_InputIteratorConcept<_IIter2>)
1095  __glibcxx_requires_valid_range(__first1, __last1);
1096 
1097  for (; __first1 != __last1; ++__first1, ++__first2)
1098  if (!bool(__binary_pred(*__first1, *__first2)))
1099  return false;
1100  return true;
1101  }
1102 
1103 #if __cplusplus > 201103L
1104 
1105 #define __cpp_lib_robust_nonmodifying_seq_ops 201304
1106 
1107  /**
1108  * @brief Tests a range for element-wise equality.
1109  * @ingroup non_mutating_algorithms
1110  * @param __first1 An input iterator.
1111  * @param __last1 An input iterator.
1112  * @param __first2 An input iterator.
1113  * @param __last2 An input iterator.
1114  * @return A boolean true or false.
1115  *
1116  * This compares the elements of two ranges using @c == and returns true or
1117  * false depending on whether all of the corresponding elements of the
1118  * ranges are equal.
1119  */
1120  template<typename _II1, typename _II2>
1121  inline bool
1122  equal(_II1 __first1, _II1 __last1, _II2 __first2, _II2 __last2)
1123  {
1124  // concept requirements
1125  __glibcxx_function_requires(_InputIteratorConcept<_II1>)
1126  __glibcxx_function_requires(_InputIteratorConcept<_II2>)
1127  __glibcxx_function_requires(_EqualOpConcept<
1128  typename iterator_traits<_II1>::value_type,
1129  typename iterator_traits<_II2>::value_type>)
1130  __glibcxx_requires_valid_range(__first1, __last1);
1131  __glibcxx_requires_valid_range(__first2, __last2);
1132 
1133  using _RATag = random_access_iterator_tag;
1134  using _Cat1 = typename iterator_traits<_II1>::iterator_category;
1135  using _Cat2 = typename iterator_traits<_II2>::iterator_category;
1136  using _RAIters = __and_<is_same<_Cat1, _RATag>, is_same<_Cat2, _RATag>>;
1137  if (_RAIters())
1138  {
1139  auto __d1 = std::distance(__first1, __last1);
1140  auto __d2 = std::distance(__first2, __last2);
1141  if (__d1 != __d2)
1142  return false;
1143  return _GLIBCXX_STD_A::equal(__first1, __last1, __first2);
1144  }
1145 
1146  for (; __first1 != __last1 && __first2 != __last2; ++__first1, ++__first2)
1147  if (!(*__first1 == *__first2))
1148  return false;
1149  return __first1 == __last1 && __first2 == __last2;
1150  }
1151 
1152  /**
1153  * @brief Tests a range for element-wise equality.
1154  * @ingroup non_mutating_algorithms
1155  * @param __first1 An input iterator.
1156  * @param __last1 An input iterator.
1157  * @param __first2 An input iterator.
1158  * @param __last2 An input iterator.
1159  * @param __binary_pred A binary predicate @link functors
1160  * functor@endlink.
1161  * @return A boolean true or false.
1162  *
1163  * This compares the elements of two ranges using the binary_pred
1164  * parameter, and returns true or
1165  * false depending on whether all of the corresponding elements of the
1166  * ranges are equal.
1167  */
1168  template<typename _IIter1, typename _IIter2, typename _BinaryPredicate>
1169  inline bool
1170  equal(_IIter1 __first1, _IIter1 __last1,
1171  _IIter2 __first2, _IIter2 __last2, _BinaryPredicate __binary_pred)
1172  {
1173  // concept requirements
1174  __glibcxx_function_requires(_InputIteratorConcept<_IIter1>)
1175  __glibcxx_function_requires(_InputIteratorConcept<_IIter2>)
1176  __glibcxx_requires_valid_range(__first1, __last1);
1177  __glibcxx_requires_valid_range(__first2, __last2);
1178 
1179  using _RATag = random_access_iterator_tag;
1180  using _Cat1 = typename iterator_traits<_IIter1>::iterator_category;
1181  using _Cat2 = typename iterator_traits<_IIter2>::iterator_category;
1182  using _RAIters = __and_<is_same<_Cat1, _RATag>, is_same<_Cat2, _RATag>>;
1183  if (_RAIters())
1184  {
1185  auto __d1 = std::distance(__first1, __last1);
1186  auto __d2 = std::distance(__first2, __last2);
1187  if (__d1 != __d2)
1188  return false;
1189  return _GLIBCXX_STD_A::equal(__first1, __last1, __first2,
1190  __binary_pred);
1191  }
1192 
1193  for (; __first1 != __last1 && __first2 != __last2; ++__first1, ++__first2)
1194  if (!bool(__binary_pred(*__first1, *__first2)))
1195  return false;
1196  return __first1 == __last1 && __first2 == __last2;
1197  }
1198 #endif
1199 
1200  /**
1201  * @brief Performs @b dictionary comparison on ranges.
1202  * @ingroup sorting_algorithms
1203  * @param __first1 An input iterator.
1204  * @param __last1 An input iterator.
1205  * @param __first2 An input iterator.
1206  * @param __last2 An input iterator.
1207  * @return A boolean true or false.
1208  *
1209  * <em>Returns true if the sequence of elements defined by the range
1210  * [first1,last1) is lexicographically less than the sequence of elements
1211  * defined by the range [first2,last2). Returns false otherwise.</em>
1212  * (Quoted from [25.3.8]/1.) If the iterators are all character pointers,
1213  * then this is an inline call to @c memcmp.
1214  */
1215  template<typename _II1, typename _II2>
1216  inline bool
1217  lexicographical_compare(_II1 __first1, _II1 __last1,
1218  _II2 __first2, _II2 __last2)
1219  {
1220 #ifdef _GLIBCXX_CONCEPT_CHECKS
1221  // concept requirements
1222  typedef typename iterator_traits<_II1>::value_type _ValueType1;
1223  typedef typename iterator_traits<_II2>::value_type _ValueType2;
1224 #endif
1225  __glibcxx_function_requires(_InputIteratorConcept<_II1>)
1226  __glibcxx_function_requires(_InputIteratorConcept<_II2>)
1227  __glibcxx_function_requires(_LessThanOpConcept<_ValueType1, _ValueType2>)
1228  __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>)
1229  __glibcxx_requires_valid_range(__first1, __last1);
1230  __glibcxx_requires_valid_range(__first2, __last2);
1231 
1232  return std::__lexicographical_compare_aux(std::__niter_base(__first1),
1233  std::__niter_base(__last1),
1234  std::__niter_base(__first2),
1235  std::__niter_base(__last2));
1236  }
1237 
1238  /**
1239  * @brief Performs @b dictionary comparison on ranges.
1240  * @ingroup sorting_algorithms
1241  * @param __first1 An input iterator.
1242  * @param __last1 An input iterator.
1243  * @param __first2 An input iterator.
1244  * @param __last2 An input iterator.
1245  * @param __comp A @link comparison_functors comparison functor@endlink.
1246  * @return A boolean true or false.
1247  *
1248  * The same as the four-parameter @c lexicographical_compare, but uses the
1249  * comp parameter instead of @c <.
1250  */
1251  template<typename _II1, typename _II2, typename _Compare>
1252  inline bool
1253  lexicographical_compare(_II1 __first1, _II1 __last1,
1254  _II2 __first2, _II2 __last2, _Compare __comp)
1255  {
1256  // concept requirements
1257  __glibcxx_function_requires(_InputIteratorConcept<_II1>)
1258  __glibcxx_function_requires(_InputIteratorConcept<_II2>)
1259  __glibcxx_requires_valid_range(__first1, __last1);
1260  __glibcxx_requires_valid_range(__first2, __last2);
1261 
1262  return std::__lexicographical_compare_impl
1263  (__first1, __last1, __first2, __last2,
1264  __gnu_cxx::__ops::__iter_comp_iter(__comp));
1265  }
1266 
1267  template<typename _InputIterator1, typename _InputIterator2,
1268  typename _BinaryPredicate>
1269  pair<_InputIterator1, _InputIterator2>
1270  __mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
1271  _InputIterator2 __first2, _BinaryPredicate __binary_pred)
1272  {
1273  while (__first1 != __last1 && __binary_pred(__first1, __first2))
1274  {
1275  ++__first1;
1276  ++__first2;
1277  }
1278  return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
1279  }
1280 
1281  /**
1282  * @brief Finds the places in ranges which don't match.
1283  * @ingroup non_mutating_algorithms
1284  * @param __first1 An input iterator.
1285  * @param __last1 An input iterator.
1286  * @param __first2 An input iterator.
1287  * @return A pair of iterators pointing to the first mismatch.
1288  *
1289  * This compares the elements of two ranges using @c == and returns a pair
1290  * of iterators. The first iterator points into the first range, the
1291  * second iterator points into the second range, and the elements pointed
1292  * to by the iterators are not equal.
1293  */
1294  template<typename _InputIterator1, typename _InputIterator2>
1295  inline pair<_InputIterator1, _InputIterator2>
1296  mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
1297  _InputIterator2 __first2)
1298  {
1299  // concept requirements
1300  __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
1301  __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
1302  __glibcxx_function_requires(_EqualOpConcept<
1303  typename iterator_traits<_InputIterator1>::value_type,
1304  typename iterator_traits<_InputIterator2>::value_type>)
1305  __glibcxx_requires_valid_range(__first1, __last1);
1306 
1307  return _GLIBCXX_STD_A::__mismatch(__first1, __last1, __first2,
1308  __gnu_cxx::__ops::__iter_equal_to_iter());
1309  }
1310 
1311  /**
1312  * @brief Finds the places in ranges which don't match.
1313  * @ingroup non_mutating_algorithms
1314  * @param __first1 An input iterator.
1315  * @param __last1 An input iterator.
1316  * @param __first2 An input iterator.
1317  * @param __binary_pred A binary predicate @link functors
1318  * functor@endlink.
1319  * @return A pair of iterators pointing to the first mismatch.
1320  *
1321  * This compares the elements of two ranges using the binary_pred
1322  * parameter, and returns a pair
1323  * of iterators. The first iterator points into the first range, the
1324  * second iterator points into the second range, and the elements pointed
1325  * to by the iterators are not equal.
1326  */
1327  template<typename _InputIterator1, typename _InputIterator2,
1328  typename _BinaryPredicate>
1329  inline pair<_InputIterator1, _InputIterator2>
1330  mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
1331  _InputIterator2 __first2, _BinaryPredicate __binary_pred)
1332  {
1333  // concept requirements
1334  __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
1335  __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
1336  __glibcxx_requires_valid_range(__first1, __last1);
1337 
1338  return _GLIBCXX_STD_A::__mismatch(__first1, __last1, __first2,
1339  __gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
1340  }
1341 
1342 #if __cplusplus > 201103L
1343 
1344  template<typename _InputIterator1, typename _InputIterator2,
1345  typename _BinaryPredicate>
1346  pair<_InputIterator1, _InputIterator2>
1347  __mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
1348  _InputIterator2 __first2, _InputIterator2 __last2,
1349  _BinaryPredicate __binary_pred)
1350  {
1351  while (__first1 != __last1 && __first2 != __last2
1352  && __binary_pred(__first1, __first2))
1353  {
1354  ++__first1;
1355  ++__first2;
1356  }
1357  return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
1358  }
1359 
1360  /**
1361  * @brief Finds the places in ranges which don't match.
1362  * @ingroup non_mutating_algorithms
1363  * @param __first1 An input iterator.
1364  * @param __last1 An input iterator.
1365  * @param __first2 An input iterator.
1366  * @param __last2 An input iterator.
1367  * @return A pair of iterators pointing to the first mismatch.
1368  *
1369  * This compares the elements of two ranges using @c == and returns a pair
1370  * of iterators. The first iterator points into the first range, the
1371  * second iterator points into the second range, and the elements pointed
1372  * to by the iterators are not equal.
1373  */
1374  template<typename _InputIterator1, typename _InputIterator2>
1375  inline pair<_InputIterator1, _InputIterator2>
1376  mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
1377  _InputIterator2 __first2, _InputIterator2 __last2)
1378  {
1379  // concept requirements
1380  __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
1381  __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
1382  __glibcxx_function_requires(_EqualOpConcept<
1383  typename iterator_traits<_InputIterator1>::value_type,
1384  typename iterator_traits<_InputIterator2>::value_type>)
1385  __glibcxx_requires_valid_range(__first1, __last1);
1386  __glibcxx_requires_valid_range(__first2, __last2);
1387 
1388  return _GLIBCXX_STD_A::__mismatch(__first1, __last1, __first2, __last2,
1389  __gnu_cxx::__ops::__iter_equal_to_iter());
1390  }
1391 
1392  /**
1393  * @brief Finds the places in ranges which don't match.
1394  * @ingroup non_mutating_algorithms
1395  * @param __first1 An input iterator.
1396  * @param __last1 An input iterator.
1397  * @param __first2 An input iterator.
1398  * @param __last2 An input iterator.
1399  * @param __binary_pred A binary predicate @link functors
1400  * functor@endlink.
1401  * @return A pair of iterators pointing to the first mismatch.
1402  *
1403  * This compares the elements of two ranges using the binary_pred
1404  * parameter, and returns a pair
1405  * of iterators. The first iterator points into the first range, the
1406  * second iterator points into the second range, and the elements pointed
1407  * to by the iterators are not equal.
1408  */
1409  template<typename _InputIterator1, typename _InputIterator2,
1410  typename _BinaryPredicate>
1411  inline pair<_InputIterator1, _InputIterator2>
1412  mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
1413  _InputIterator2 __first2, _InputIterator2 __last2,
1414  _BinaryPredicate __binary_pred)
1415  {
1416  // concept requirements
1417  __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
1418  __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
1419  __glibcxx_requires_valid_range(__first1, __last1);
1420  __glibcxx_requires_valid_range(__first2, __last2);
1421 
1422  return _GLIBCXX_STD_A::__mismatch(__first1, __last1, __first2, __last2,
1423  __gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
1424  }
1425 #endif
1426 
1427 _GLIBCXX_END_NAMESPACE_ALGO
1428 } // namespace std
1429 
1430 // NB: This file is included within many other C++ includes, as a way
1431 // of getting the base algorithms. So, make sure that parallel bits
1432 // come in too if requested.
1433 #ifdef _GLIBCXX_PARALLEL
1434 # include <parallel/algobase.h>
1435 #endif
1436 
1437 #endif
std::advance
void advance(_InputIterator &__i, _Distance __n)
A generalization of pointer arithmetic.
Definition: stl_iterator_base_funcs.h:173
std::char_traits
Basis for explicit traits specializations.
Definition: char_traits.h:227
std::istreambuf_iterator
Provides input iterator semantics for streambufs.
Definition: iosfwd:125
std::ostreambuf_iterator
Provides output iterator semantics for streambufs.
Definition: iosfwd:128
std::iter_swap
void iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
Swaps the contents of two iterators.
Definition: stl_algobase.h:120
std::distance
iterator_traits< _InputIterator >::difference_type distance(_InputIterator __first, _InputIterator __last)
A generalization of pointer arithmetic.
Definition: stl_iterator_base_funcs.h:114
std::move
_OI move(_II __first, _II __last, _OI __result)
Moves the range [first,last) into result.
Definition: stl_algobase.h:495
std::equal
bool equal(_IIter1 __first1, _IIter1 __last1, _IIter2 __first2, _IIter2 __last2, _BinaryPredicate __binary_pred)
Tests a range for element-wise equality.
Definition: stl_algobase.h:1170
std::min
_GLIBCXX14_CONSTEXPR const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:195
std::max
_GLIBCXX14_CONSTEXPR const _Tp & max(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:219
std::__lg
constexpr int __lg(int __n)
This is a helper function for the sort routines and for random.tcc.
Definition: stl_algobase.h:1016
algobase.h
Parallel STL function calls corresponding to the stl_algobase.h header. The functions defined here ma...
std::copy
_OI copy(_II __first, _II __last, _OI __result)
Copies the range [first,last) into result.
Definition: stl_algobase.h:462
std::pair
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:96
std
ISO C++ entities toplevel namespace is std.