libstdc++
stl_queue.h
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1 // Queue implementation -*- C++ -*-
2 
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24 
25 /*
26  *
27  * Copyright (c) 1994
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29  *
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41  *
42  * Permission to use, copy, modify, distribute and sell this software
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49  */
50 
51 /** @file bits/stl_queue.h
52  * This is an internal header file, included by other library headers.
53  * Do not attempt to use it directly. @headername{queue}
54  */
55 
56 #ifndef _STL_QUEUE_H
57 #define _STL_QUEUE_H 1
58 
59 #include <bits/concept_check.h>
60 #include <debug/debug.h>
61 #if __cplusplus >= 201103L
62 # include <bits/uses_allocator.h>
63 #endif
64 
65 namespace std _GLIBCXX_VISIBILITY(default)
66 {
67 _GLIBCXX_BEGIN_NAMESPACE_VERSION
68 
69  /**
70  * @brief A standard container giving FIFO behavior.
71  *
72  * @ingroup sequences
73  *
74  * @tparam _Tp Type of element.
75  * @tparam _Sequence Type of underlying sequence, defaults to deque<_Tp>.
76  *
77  * Meets many of the requirements of a
78  * <a href="tables.html#65">container</a>,
79  * but does not define anything to do with iterators. Very few of the
80  * other standard container interfaces are defined.
81  *
82  * This is not a true container, but an @e adaptor. It holds another
83  * container, and provides a wrapper interface to that container. The
84  * wrapper is what enforces strict first-in-first-out %queue behavior.
85  *
86  * The second template parameter defines the type of the underlying
87  * sequence/container. It defaults to std::deque, but it can be any type
88  * that supports @c front, @c back, @c push_back, and @c pop_front,
89  * such as std::list or an appropriate user-defined type.
90  *
91  * Members not found in @a normal containers are @c container_type,
92  * which is a typedef for the second Sequence parameter, and @c push and
93  * @c pop, which are standard %queue/FIFO operations.
94  */
95  template<typename _Tp, typename _Sequence = deque<_Tp> >
96  class queue
97  {
98 #ifdef _GLIBCXX_CONCEPT_CHECKS
99  // concept requirements
100  typedef typename _Sequence::value_type _Sequence_value_type;
101 # if __cplusplus < 201103L
102  __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
103 # endif
104  __glibcxx_class_requires(_Sequence, _FrontInsertionSequenceConcept)
105  __glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept)
106  __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
107 #endif
108 
109  template<typename _Tp1, typename _Seq1>
110  friend bool
111  operator==(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
112 
113  template<typename _Tp1, typename _Seq1>
114  friend bool
115  operator<(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
116 
117 #if __cpp_lib_three_way_comparison
118  template<typename _Tp1, three_way_comparable _Seq1>
119  friend compare_three_way_result_t<_Seq1>
120  operator<=>(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
121 #endif
122 
123 #if __cplusplus >= 201103L
124  template<typename _Alloc>
125  using _Uses = typename
127 
128 #if __cplusplus >= 201703L
129  // _GLIBCXX_RESOLVE_LIB_DEFECTS
130  // 2566. Requirements on the first template parameter of container
131  // adaptors
133  "value_type must be the same as the underlying container");
134 #endif // C++17
135 #endif // C++11
136 
137  public:
138  typedef typename _Sequence::value_type value_type;
139  typedef typename _Sequence::reference reference;
140  typedef typename _Sequence::const_reference const_reference;
141  typedef typename _Sequence::size_type size_type;
142  typedef _Sequence container_type;
143 
144  protected:
145  /* Maintainers wondering why this isn't uglified as per style
146  * guidelines should note that this name is specified in the standard,
147  * C++98 [23.2.3.1].
148  * (Why? Presumably for the same reason that it's protected instead
149  * of private: to allow derivation. But none of the other
150  * containers allow for derivation. Odd.)
151  */
152  /// @c c is the underlying container.
153  _Sequence c;
154 
155  public:
156  /**
157  * @brief Default constructor creates no elements.
158  */
159 #if __cplusplus < 201103L
160  explicit
161  queue(const _Sequence& __c = _Sequence())
162  : c(__c) { }
163 #else
164  template<typename _Seq = _Sequence, typename _Requires = typename
167  : c() { }
168 
169  explicit
170  queue(const _Sequence& __c)
171  : c(__c) { }
172 
173  explicit
174  queue(_Sequence&& __c)
175  : c(std::move(__c)) { }
176 
177  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
178  explicit
179  queue(const _Alloc& __a)
180  : c(__a) { }
181 
182  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
183  queue(const _Sequence& __c, const _Alloc& __a)
184  : c(__c, __a) { }
185 
186  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
187  queue(_Sequence&& __c, const _Alloc& __a)
188  : c(std::move(__c), __a) { }
189 
190  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
191  queue(const queue& __q, const _Alloc& __a)
192  : c(__q.c, __a) { }
193 
194  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
195  queue(queue&& __q, const _Alloc& __a)
196  : c(std::move(__q.c), __a) { }
197 #endif
198 
199  /**
200  * Returns true if the %queue is empty.
201  */
202  _GLIBCXX_NODISCARD bool
203  empty() const
204  { return c.empty(); }
205 
206  /** Returns the number of elements in the %queue. */
207  size_type
208  size() const
209  { return c.size(); }
210 
211  /**
212  * Returns a read/write reference to the data at the first
213  * element of the %queue.
214  */
215  reference
217  {
218  __glibcxx_requires_nonempty();
219  return c.front();
220  }
221 
222  /**
223  * Returns a read-only (constant) reference to the data at the first
224  * element of the %queue.
225  */
226  const_reference
227  front() const
228  {
229  __glibcxx_requires_nonempty();
230  return c.front();
231  }
232 
233  /**
234  * Returns a read/write reference to the data at the last
235  * element of the %queue.
236  */
237  reference
239  {
240  __glibcxx_requires_nonempty();
241  return c.back();
242  }
243 
244  /**
245  * Returns a read-only (constant) reference to the data at the last
246  * element of the %queue.
247  */
248  const_reference
249  back() const
250  {
251  __glibcxx_requires_nonempty();
252  return c.back();
253  }
254 
255  /**
256  * @brief Add data to the end of the %queue.
257  * @param __x Data to be added.
258  *
259  * This is a typical %queue operation. The function creates an
260  * element at the end of the %queue and assigns the given data
261  * to it. The time complexity of the operation depends on the
262  * underlying sequence.
263  */
264  void
265  push(const value_type& __x)
266  { c.push_back(__x); }
267 
268 #if __cplusplus >= 201103L
269  void
270  push(value_type&& __x)
271  { c.push_back(std::move(__x)); }
272 
273 #if __cplusplus > 201402L
274  template<typename... _Args>
275  decltype(auto)
276  emplace(_Args&&... __args)
277  { return c.emplace_back(std::forward<_Args>(__args)...); }
278 #else
279  template<typename... _Args>
280  void
281  emplace(_Args&&... __args)
282  { c.emplace_back(std::forward<_Args>(__args)...); }
283 #endif
284 #endif
285 
286  /**
287  * @brief Removes first element.
288  *
289  * This is a typical %queue operation. It shrinks the %queue by one.
290  * The time complexity of the operation depends on the underlying
291  * sequence.
292  *
293  * Note that no data is returned, and if the first element's
294  * data is needed, it should be retrieved before pop() is
295  * called.
296  */
297  void
298  pop()
299  {
300  __glibcxx_requires_nonempty();
301  c.pop_front();
302  }
303 
304 #if __cplusplus >= 201103L
305  void
306  swap(queue& __q)
307 #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
308  noexcept(__is_nothrow_swappable<_Sequence>::value)
309 #else
310  noexcept(__is_nothrow_swappable<_Tp>::value)
311 #endif
312  {
313  using std::swap;
314  swap(c, __q.c);
315  }
316 #endif // __cplusplus >= 201103L
317  };
318 
319 #if __cpp_deduction_guides >= 201606
320  template<typename _Container,
321  typename = _RequireNotAllocator<_Container>>
322  queue(_Container) -> queue<typename _Container::value_type, _Container>;
323 
324  template<typename _Container, typename _Allocator,
325  typename = _RequireNotAllocator<_Container>,
326  typename = _RequireAllocator<_Allocator>>
327  queue(_Container, _Allocator)
328  -> queue<typename _Container::value_type, _Container>;
329 #endif
330 
331  /**
332  * @brief Queue equality comparison.
333  * @param __x A %queue.
334  * @param __y A %queue of the same type as @a __x.
335  * @return True iff the size and elements of the queues are equal.
336  *
337  * This is an equivalence relation. Complexity and semantics depend on the
338  * underlying sequence type, but the expected rules are: this relation is
339  * linear in the size of the sequences, and queues are considered equivalent
340  * if their sequences compare equal.
341  */
342  template<typename _Tp, typename _Seq>
343  inline bool
344  operator==(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
345  { return __x.c == __y.c; }
346 
347  /**
348  * @brief Queue ordering relation.
349  * @param __x A %queue.
350  * @param __y A %queue of the same type as @a x.
351  * @return True iff @a __x is lexicographically less than @a __y.
352  *
353  * This is an total ordering relation. Complexity and semantics
354  * depend on the underlying sequence type, but the expected rules
355  * are: this relation is linear in the size of the sequences, the
356  * elements must be comparable with @c <, and
357  * std::lexicographical_compare() is usually used to make the
358  * determination.
359  */
360  template<typename _Tp, typename _Seq>
361  inline bool
362  operator<(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
363  { return __x.c < __y.c; }
364 
365  /// Based on operator==
366  template<typename _Tp, typename _Seq>
367  inline bool
368  operator!=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
369  { return !(__x == __y); }
370 
371  /// Based on operator<
372  template<typename _Tp, typename _Seq>
373  inline bool
374  operator>(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
375  { return __y < __x; }
376 
377  /// Based on operator<
378  template<typename _Tp, typename _Seq>
379  inline bool
380  operator<=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
381  { return !(__y < __x); }
382 
383  /// Based on operator<
384  template<typename _Tp, typename _Seq>
385  inline bool
386  operator>=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
387  { return !(__x < __y); }
388 
389 #if __cpp_lib_three_way_comparison
390  template<typename _Tp, three_way_comparable _Seq>
391  inline compare_three_way_result_t<_Seq>
392  operator<=>(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
393  { return __x.c <=> __y.c; }
394 #endif
395 
396 #if __cplusplus >= 201103L
397  template<typename _Tp, typename _Seq>
398  inline
399 #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
400  // Constrained free swap overload, see p0185r1
401  typename enable_if<__is_swappable<_Seq>::value>::type
402 #else
403  void
404 #endif
405  swap(queue<_Tp, _Seq>& __x, queue<_Tp, _Seq>& __y)
406  noexcept(noexcept(__x.swap(__y)))
407  { __x.swap(__y); }
408 
409  template<typename _Tp, typename _Seq, typename _Alloc>
410  struct uses_allocator<queue<_Tp, _Seq>, _Alloc>
411  : public uses_allocator<_Seq, _Alloc>::type { };
412 #endif // __cplusplus >= 201103L
413 
414  /**
415  * @brief A standard container automatically sorting its contents.
416  *
417  * @ingroup sequences
418  *
419  * @tparam _Tp Type of element.
420  * @tparam _Sequence Type of underlying sequence, defaults to vector<_Tp>.
421  * @tparam _Compare Comparison function object type, defaults to
422  * less<_Sequence::value_type>.
423  *
424  * This is not a true container, but an @e adaptor. It holds
425  * another container, and provides a wrapper interface to that
426  * container. The wrapper is what enforces priority-based sorting
427  * and %queue behavior. Very few of the standard container/sequence
428  * interface requirements are met (e.g., iterators).
429  *
430  * The second template parameter defines the type of the underlying
431  * sequence/container. It defaults to std::vector, but it can be
432  * any type that supports @c front(), @c push_back, @c pop_back,
433  * and random-access iterators, such as std::deque or an
434  * appropriate user-defined type.
435  *
436  * The third template parameter supplies the means of making
437  * priority comparisons. It defaults to @c less<value_type> but
438  * can be anything defining a strict weak ordering.
439  *
440  * Members not found in @a normal containers are @c container_type,
441  * which is a typedef for the second Sequence parameter, and @c
442  * push, @c pop, and @c top, which are standard %queue operations.
443  *
444  * @note No equality/comparison operators are provided for
445  * %priority_queue.
446  *
447  * @note Sorting of the elements takes place as they are added to,
448  * and removed from, the %priority_queue using the
449  * %priority_queue's member functions. If you access the elements
450  * by other means, and change their data such that the sorting
451  * order would be different, the %priority_queue will not re-sort
452  * the elements for you. (How could it know to do so?)
453  */
454  template<typename _Tp, typename _Sequence = vector<_Tp>,
455  typename _Compare = less<typename _Sequence::value_type> >
457  {
458 #ifdef _GLIBCXX_CONCEPT_CHECKS
459  // concept requirements
460  typedef typename _Sequence::value_type _Sequence_value_type;
461 # if __cplusplus < 201103L
462  __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
463 # endif
464  __glibcxx_class_requires(_Sequence, _SequenceConcept)
465  __glibcxx_class_requires(_Sequence, _RandomAccessContainerConcept)
466  __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
467  __glibcxx_class_requires4(_Compare, bool, _Tp, _Tp,
468  _BinaryFunctionConcept)
469 #endif
470 
471 #if __cplusplus >= 201103L
472  template<typename _Alloc>
473  using _Uses = typename
475 
476 #if __cplusplus >= 201703L
477  // _GLIBCXX_RESOLVE_LIB_DEFECTS
478  // 2566. Requirements on the first template parameter of container
479  // adaptors
481  "value_type must be the same as the underlying container");
482 #endif // C++17
483 #endif // C++11
484 
485  public:
486  typedef typename _Sequence::value_type value_type;
487  typedef typename _Sequence::reference reference;
488  typedef typename _Sequence::const_reference const_reference;
489  typedef typename _Sequence::size_type size_type;
490  typedef _Sequence container_type;
491  // _GLIBCXX_RESOLVE_LIB_DEFECTS
492  // DR 2684. priority_queue lacking comparator typedef
493  typedef _Compare value_compare;
494 
495  protected:
496  // See queue::c for notes on these names.
497  _Sequence c;
498  _Compare comp;
499 
500  public:
501  /**
502  * @brief Default constructor creates no elements.
503  */
504 #if __cplusplus < 201103L
505  explicit
506  priority_queue(const _Compare& __x = _Compare(),
507  const _Sequence& __s = _Sequence())
508  : c(__s), comp(__x)
509  { std::make_heap(c.begin(), c.end(), comp); }
510 #else
511  template<typename _Seq = _Sequence, typename _Requires = typename
513  is_default_constructible<_Seq>>::value>::type>
515  : c(), comp() { }
516 
517  explicit
518  priority_queue(const _Compare& __x, const _Sequence& __s)
519  : c(__s), comp(__x)
520  { std::make_heap(c.begin(), c.end(), comp); }
521 
522  explicit
523  priority_queue(const _Compare& __x, _Sequence&& __s = _Sequence())
524  : c(std::move(__s)), comp(__x)
525  { std::make_heap(c.begin(), c.end(), comp); }
526 
527  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
528  explicit
529  priority_queue(const _Alloc& __a)
530  : c(__a), comp() { }
531 
532  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
533  priority_queue(const _Compare& __x, const _Alloc& __a)
534  : c(__a), comp(__x) { }
535 
536  // _GLIBCXX_RESOLVE_LIB_DEFECTS
537  // 2537. Constructors [...] taking allocators should call make_heap
538  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
539  priority_queue(const _Compare& __x, const _Sequence& __c,
540  const _Alloc& __a)
541  : c(__c, __a), comp(__x)
542  { std::make_heap(c.begin(), c.end(), comp); }
543 
544  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
545  priority_queue(const _Compare& __x, _Sequence&& __c, const _Alloc& __a)
546  : c(std::move(__c), __a), comp(__x)
547  { std::make_heap(c.begin(), c.end(), comp); }
548 
549  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
550  priority_queue(const priority_queue& __q, const _Alloc& __a)
551  : c(__q.c, __a), comp(__q.comp) { }
552 
553  template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
554  priority_queue(priority_queue&& __q, const _Alloc& __a)
555  : c(std::move(__q.c), __a), comp(std::move(__q.comp)) { }
556 #endif
557 
558  /**
559  * @brief Builds a %queue from a range.
560  * @param __first An input iterator.
561  * @param __last An input iterator.
562  * @param __x A comparison functor describing a strict weak ordering.
563  * @param __s An initial sequence with which to start.
564  *
565  * Begins by copying @a __s, inserting a copy of the elements
566  * from @a [first,last) into the copy of @a __s, then ordering
567  * the copy according to @a __x.
568  *
569  * For more information on function objects, see the
570  * documentation on @link functors functor base
571  * classes@endlink.
572  */
573 #if __cplusplus < 201103L
574  template<typename _InputIterator>
575  priority_queue(_InputIterator __first, _InputIterator __last,
576  const _Compare& __x = _Compare(),
577  const _Sequence& __s = _Sequence())
578  : c(__s), comp(__x)
579  {
580  __glibcxx_requires_valid_range(__first, __last);
581  c.insert(c.end(), __first, __last);
582  std::make_heap(c.begin(), c.end(), comp);
583  }
584 #else
585  template<typename _InputIterator>
586  priority_queue(_InputIterator __first, _InputIterator __last,
587  const _Compare& __x,
588  const _Sequence& __s)
589  : c(__s), comp(__x)
590  {
591  __glibcxx_requires_valid_range(__first, __last);
592  c.insert(c.end(), __first, __last);
593  std::make_heap(c.begin(), c.end(), comp);
594  }
595 
596  template<typename _InputIterator>
597  priority_queue(_InputIterator __first, _InputIterator __last,
598  const _Compare& __x = _Compare(),
599  _Sequence&& __s = _Sequence())
600  : c(std::move(__s)), comp(__x)
601  {
602  __glibcxx_requires_valid_range(__first, __last);
603  c.insert(c.end(), __first, __last);
604  std::make_heap(c.begin(), c.end(), comp);
605  }
606 #endif
607 
608  /**
609  * Returns true if the %queue is empty.
610  */
611  _GLIBCXX_NODISCARD bool
612  empty() const
613  { return c.empty(); }
614 
615  /** Returns the number of elements in the %queue. */
616  size_type
617  size() const
618  { return c.size(); }
619 
620  /**
621  * Returns a read-only (constant) reference to the data at the first
622  * element of the %queue.
623  */
624  const_reference
625  top() const
626  {
627  __glibcxx_requires_nonempty();
628  return c.front();
629  }
630 
631  /**
632  * @brief Add data to the %queue.
633  * @param __x Data to be added.
634  *
635  * This is a typical %queue operation.
636  * The time complexity of the operation depends on the underlying
637  * sequence.
638  */
639  void
640  push(const value_type& __x)
641  {
642  c.push_back(__x);
643  std::push_heap(c.begin(), c.end(), comp);
644  }
645 
646 #if __cplusplus >= 201103L
647  void
648  push(value_type&& __x)
649  {
650  c.push_back(std::move(__x));
651  std::push_heap(c.begin(), c.end(), comp);
652  }
653 
654  template<typename... _Args>
655  void
656  emplace(_Args&&... __args)
657  {
658  c.emplace_back(std::forward<_Args>(__args)...);
659  std::push_heap(c.begin(), c.end(), comp);
660  }
661 #endif
662 
663  /**
664  * @brief Removes first element.
665  *
666  * This is a typical %queue operation. It shrinks the %queue
667  * by one. The time complexity of the operation depends on the
668  * underlying sequence.
669  *
670  * Note that no data is returned, and if the first element's
671  * data is needed, it should be retrieved before pop() is
672  * called.
673  */
674  void
675  pop()
676  {
677  __glibcxx_requires_nonempty();
678  std::pop_heap(c.begin(), c.end(), comp);
679  c.pop_back();
680  }
681 
682 #if __cplusplus >= 201103L
683  void
684  swap(priority_queue& __pq)
685  noexcept(__and_<
686 #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
687  __is_nothrow_swappable<_Sequence>,
688 #else
689  __is_nothrow_swappable<_Tp>,
690 #endif
691  __is_nothrow_swappable<_Compare>
692  >::value)
693  {
694  using std::swap;
695  swap(c, __pq.c);
696  swap(comp, __pq.comp);
697  }
698 #endif // __cplusplus >= 201103L
699  };
700 
701 #if __cpp_deduction_guides >= 201606
702  template<typename _Compare, typename _Container,
703  typename = _RequireNotAllocator<_Compare>,
704  typename = _RequireNotAllocator<_Container>>
705  priority_queue(_Compare, _Container)
706  -> priority_queue<typename _Container::value_type, _Container, _Compare>;
707 
708  template<typename _InputIterator, typename _ValT
709  = typename iterator_traits<_InputIterator>::value_type,
710  typename _Compare = less<_ValT>,
711  typename _Container = vector<_ValT>,
712  typename = _RequireInputIter<_InputIterator>,
713  typename = _RequireNotAllocator<_Compare>,
714  typename = _RequireNotAllocator<_Container>>
715  priority_queue(_InputIterator, _InputIterator, _Compare = _Compare(),
716  _Container = _Container())
717  -> priority_queue<_ValT, _Container, _Compare>;
718 
719  template<typename _Compare, typename _Container, typename _Allocator,
720  typename = _RequireNotAllocator<_Compare>,
721  typename = _RequireNotAllocator<_Container>,
722  typename = _RequireAllocator<_Allocator>>
723  priority_queue(_Compare, _Container, _Allocator)
724  -> priority_queue<typename _Container::value_type, _Container, _Compare>;
725 #endif
726 
727  // No equality/comparison operators are provided for priority_queue.
728 
729 #if __cplusplus >= 201103L
730  template<typename _Tp, typename _Sequence, typename _Compare>
731  inline
732 #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
733  // Constrained free swap overload, see p0185r1
734  typename enable_if<__and_<__is_swappable<_Sequence>,
735  __is_swappable<_Compare>>::value>::type
736 #else
737  void
738 #endif
739  swap(priority_queue<_Tp, _Sequence, _Compare>& __x,
740  priority_queue<_Tp, _Sequence, _Compare>& __y)
741  noexcept(noexcept(__x.swap(__y)))
742  { __x.swap(__y); }
743 
744  template<typename _Tp, typename _Sequence, typename _Compare,
745  typename _Alloc>
746  struct uses_allocator<priority_queue<_Tp, _Sequence, _Compare>, _Alloc>
747  : public uses_allocator<_Sequence, _Alloc>::type { };
748 #endif // __cplusplus >= 201103L
749 
750 _GLIBCXX_END_NAMESPACE_VERSION
751 } // namespace
752 
753 #endif /* _STL_QUEUE_H */
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Definition: move.h:104
void swap(any &__x, any &__y) noexcept
Exchange the states of two any objects.
Definition: any:422
ISO C++ entities toplevel namespace is std.
is_same
Definition: type_traits:1410
is_default_constructible
Definition: type_traits:963
Define a member typedef type only if a boolean constant is true.
Definition: type_traits:2200
A standard container giving FIFO behavior.
Definition: stl_queue.h:97
void push(const value_type &__x)
Add data to the end of the queue.
Definition: stl_queue.h:265
_Sequence c
c is the underlying container.
Definition: stl_queue.h:153
size_type size() const
Definition: stl_queue.h:208
reference front()
Definition: stl_queue.h:216
const_reference back() const
Definition: stl_queue.h:249
void pop()
Removes first element.
Definition: stl_queue.h:298
queue()
Default constructor creates no elements.
Definition: stl_queue.h:166
const_reference front() const
Definition: stl_queue.h:227
bool empty() const
Definition: stl_queue.h:203
reference back()
Definition: stl_queue.h:238
A standard container automatically sorting its contents.
Definition: stl_queue.h:457
size_type size() const
Definition: stl_queue.h:617
bool empty() const
Definition: stl_queue.h:612
priority_queue(_InputIterator __first, _InputIterator __last, const _Compare &__x, const _Sequence &__s)
Builds a queue from a range.
Definition: stl_queue.h:586
void pop()
Removes first element.
Definition: stl_queue.h:675
const_reference top() const
Definition: stl_queue.h:625
void push(const value_type &__x)
Add data to the queue.
Definition: stl_queue.h:640
priority_queue()
Default constructor creates no elements.
Definition: stl_queue.h:514