libstdc++
stl_map.h
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1 // Map implementation -*- C++ -*-
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25 /*
26  *
27  * Copyright (c) 1994
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29  *
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42  * Permission to use, copy, modify, distribute and sell this software
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49  */
50 
51 /** @file bits/stl_map.h
52  * This is an internal header file, included by other library headers.
53  * Do not attempt to use it directly. @headername{map}
54  */
55 
56 #ifndef _STL_MAP_H
57 #define _STL_MAP_H 1
58 
59 #include <bits/functexcept.h>
60 #include <bits/concept_check.h>
61 #if __cplusplus >= 201103L
62 #include <initializer_list>
63 #include <tuple>
64 #endif
65 
66 namespace std _GLIBCXX_VISIBILITY(default)
67 {
68 _GLIBCXX_BEGIN_NAMESPACE_VERSION
69 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
70 
71  template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
72  class multimap;
73 
74  /**
75  * @brief A standard container made up of (key,value) pairs, which can be
76  * retrieved based on a key, in logarithmic time.
77  *
78  * @ingroup associative_containers
79  *
80  * @tparam _Key Type of key objects.
81  * @tparam _Tp Type of mapped objects.
82  * @tparam _Compare Comparison function object type, defaults to less<_Key>.
83  * @tparam _Alloc Allocator type, defaults to
84  * allocator<pair<const _Key, _Tp>.
85  *
86  * Meets the requirements of a <a href="tables.html#65">container</a>, a
87  * <a href="tables.html#66">reversible container</a>, and an
88  * <a href="tables.html#69">associative container</a> (using unique keys).
89  * For a @c map<Key,T> the key_type is Key, the mapped_type is T, and the
90  * value_type is std::pair<const Key,T>.
91  *
92  * Maps support bidirectional iterators.
93  *
94  * The private tree data is declared exactly the same way for map and
95  * multimap; the distinction is made entirely in how the tree functions are
96  * called (*_unique versus *_equal, same as the standard).
97  */
98  template <typename _Key, typename _Tp, typename _Compare = std::less<_Key>,
99  typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
100  class map
101  {
102  public:
103  typedef _Key key_type;
104  typedef _Tp mapped_type;
106  typedef _Compare key_compare;
107  typedef _Alloc allocator_type;
108 
109  private:
110 #ifdef _GLIBCXX_CONCEPT_CHECKS
111  // concept requirements
112  typedef typename _Alloc::value_type _Alloc_value_type;
113 # if __cplusplus < 201103L
114  __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
115 # endif
116  __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
117  _BinaryFunctionConcept)
118  __glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept)
119 #endif
120 
121 #if __cplusplus >= 201103L && defined(__STRICT_ANSI__)
123  "std::map must have the same value_type as its allocator");
124 #endif
125 
126  public:
127  class value_compare
128  : public std::binary_function<value_type, value_type, bool>
129  {
130  friend class map<_Key, _Tp, _Compare, _Alloc>;
131  protected:
132  _Compare comp;
133 
134  value_compare(_Compare __c)
135  : comp(__c) { }
136 
137  public:
138  bool operator()(const value_type& __x, const value_type& __y) const
139  { return comp(__x.first, __y.first); }
140  };
141 
142  private:
143  /// This turns a red-black tree into a [multi]map.
145  rebind<value_type>::other _Pair_alloc_type;
146 
147  typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
148  key_compare, _Pair_alloc_type> _Rep_type;
149 
150  /// The actual tree structure.
151  _Rep_type _M_t;
152 
154 
155  public:
156  // many of these are specified differently in ISO, but the following are
157  // "functionally equivalent"
158  typedef typename _Alloc_traits::pointer pointer;
159  typedef typename _Alloc_traits::const_pointer const_pointer;
160  typedef typename _Alloc_traits::reference reference;
161  typedef typename _Alloc_traits::const_reference const_reference;
162  typedef typename _Rep_type::iterator iterator;
163  typedef typename _Rep_type::const_iterator const_iterator;
164  typedef typename _Rep_type::size_type size_type;
165  typedef typename _Rep_type::difference_type difference_type;
168 
169 #if __cplusplus > 201402L
170  using node_type = typename _Rep_type::node_type;
171  using insert_return_type = typename _Rep_type::insert_return_type;
172 #endif
173 
174  // [23.3.1.1] construct/copy/destroy
175  // (get_allocator() is also listed in this section)
176 
177  /**
178  * @brief Default constructor creates no elements.
179  */
180 #if __cplusplus < 201103L
181  map() : _M_t() { }
182 #else
183  map() = default;
184 #endif
185 
186  /**
187  * @brief Creates a %map with no elements.
188  * @param __comp A comparison object.
189  * @param __a An allocator object.
190  */
191  explicit
192  map(const _Compare& __comp,
193  const allocator_type& __a = allocator_type())
194  : _M_t(__comp, _Pair_alloc_type(__a)) { }
195 
196  /**
197  * @brief %Map copy constructor.
198  *
199  * Whether the allocator is copied depends on the allocator traits.
200  */
201 #if __cplusplus < 201103L
202  map(const map& __x)
203  : _M_t(__x._M_t) { }
204 #else
205  map(const map&) = default;
206 
207  /**
208  * @brief %Map move constructor.
209  *
210  * The newly-created %map contains the exact contents of the moved
211  * instance. The moved instance is a valid, but unspecified, %map.
212  */
213  map(map&&) = default;
214 
215  /**
216  * @brief Builds a %map from an initializer_list.
217  * @param __l An initializer_list.
218  * @param __comp A comparison object.
219  * @param __a An allocator object.
220  *
221  * Create a %map consisting of copies of the elements in the
222  * initializer_list @a __l.
223  * This is linear in N if the range is already sorted, and NlogN
224  * otherwise (where N is @a __l.size()).
225  */
227  const _Compare& __comp = _Compare(),
228  const allocator_type& __a = allocator_type())
229  : _M_t(__comp, _Pair_alloc_type(__a))
230  { _M_t._M_insert_unique(__l.begin(), __l.end()); }
231 
232  /// Allocator-extended default constructor.
233  explicit
234  map(const allocator_type& __a)
235  : _M_t(_Compare(), _Pair_alloc_type(__a)) { }
236 
237  /// Allocator-extended copy constructor.
238  map(const map& __m, const allocator_type& __a)
239  : _M_t(__m._M_t, _Pair_alloc_type(__a)) { }
240 
241  /// Allocator-extended move constructor.
242  map(map&& __m, const allocator_type& __a)
244  && _Alloc_traits::_S_always_equal())
245  : _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { }
246 
247  /// Allocator-extended initialier-list constructor.
248  map(initializer_list<value_type> __l, const allocator_type& __a)
249  : _M_t(_Compare(), _Pair_alloc_type(__a))
250  { _M_t._M_insert_unique(__l.begin(), __l.end()); }
251 
252  /// Allocator-extended range constructor.
253  template<typename _InputIterator>
254  map(_InputIterator __first, _InputIterator __last,
255  const allocator_type& __a)
256  : _M_t(_Compare(), _Pair_alloc_type(__a))
257  { _M_t._M_insert_unique(__first, __last); }
258 #endif
259 
260  /**
261  * @brief Builds a %map from a range.
262  * @param __first An input iterator.
263  * @param __last An input iterator.
264  *
265  * Create a %map consisting of copies of the elements from
266  * [__first,__last). This is linear in N if the range is
267  * already sorted, and NlogN otherwise (where N is
268  * distance(__first,__last)).
269  */
270  template<typename _InputIterator>
271  map(_InputIterator __first, _InputIterator __last)
272  : _M_t()
273  { _M_t._M_insert_unique(__first, __last); }
274 
275  /**
276  * @brief Builds a %map from a range.
277  * @param __first An input iterator.
278  * @param __last An input iterator.
279  * @param __comp A comparison functor.
280  * @param __a An allocator object.
281  *
282  * Create a %map consisting of copies of the elements from
283  * [__first,__last). This is linear in N if the range is
284  * already sorted, and NlogN otherwise (where N is
285  * distance(__first,__last)).
286  */
287  template<typename _InputIterator>
288  map(_InputIterator __first, _InputIterator __last,
289  const _Compare& __comp,
290  const allocator_type& __a = allocator_type())
291  : _M_t(__comp, _Pair_alloc_type(__a))
292  { _M_t._M_insert_unique(__first, __last); }
293 
294 #if __cplusplus >= 201103L
295  /**
296  * The dtor only erases the elements, and note that if the elements
297  * themselves are pointers, the pointed-to memory is not touched in any
298  * way. Managing the pointer is the user's responsibility.
299  */
300  ~map() = default;
301 #endif
302 
303  /**
304  * @brief %Map assignment operator.
305  *
306  * Whether the allocator is copied depends on the allocator traits.
307  */
308 #if __cplusplus < 201103L
309  map&
310  operator=(const map& __x)
311  {
312  _M_t = __x._M_t;
313  return *this;
314  }
315 #else
316  map&
317  operator=(const map&) = default;
318 
319  /// Move assignment operator.
320  map&
321  operator=(map&&) = default;
322 
323  /**
324  * @brief %Map list assignment operator.
325  * @param __l An initializer_list.
326  *
327  * This function fills a %map with copies of the elements in the
328  * initializer list @a __l.
329  *
330  * Note that the assignment completely changes the %map and
331  * that the resulting %map's size is the same as the number
332  * of elements assigned.
333  */
334  map&
336  {
337  _M_t._M_assign_unique(__l.begin(), __l.end());
338  return *this;
339  }
340 #endif
341 
342  /// Get a copy of the memory allocation object.
343  allocator_type
344  get_allocator() const _GLIBCXX_NOEXCEPT
345  { return allocator_type(_M_t.get_allocator()); }
346 
347  // iterators
348  /**
349  * Returns a read/write iterator that points to the first pair in the
350  * %map.
351  * Iteration is done in ascending order according to the keys.
352  */
353  iterator
354  begin() _GLIBCXX_NOEXCEPT
355  { return _M_t.begin(); }
356 
357  /**
358  * Returns a read-only (constant) iterator that points to the first pair
359  * in the %map. Iteration is done in ascending order according to the
360  * keys.
361  */
362  const_iterator
363  begin() const _GLIBCXX_NOEXCEPT
364  { return _M_t.begin(); }
365 
366  /**
367  * Returns a read/write iterator that points one past the last
368  * pair in the %map. Iteration is done in ascending order
369  * according to the keys.
370  */
371  iterator
372  end() _GLIBCXX_NOEXCEPT
373  { return _M_t.end(); }
374 
375  /**
376  * Returns a read-only (constant) iterator that points one past the last
377  * pair in the %map. Iteration is done in ascending order according to
378  * the keys.
379  */
380  const_iterator
381  end() const _GLIBCXX_NOEXCEPT
382  { return _M_t.end(); }
383 
384  /**
385  * Returns a read/write reverse iterator that points to the last pair in
386  * the %map. Iteration is done in descending order according to the
387  * keys.
388  */
390  rbegin() _GLIBCXX_NOEXCEPT
391  { return _M_t.rbegin(); }
392 
393  /**
394  * Returns a read-only (constant) reverse iterator that points to the
395  * last pair in the %map. Iteration is done in descending order
396  * according to the keys.
397  */
398  const_reverse_iterator
399  rbegin() const _GLIBCXX_NOEXCEPT
400  { return _M_t.rbegin(); }
401 
402  /**
403  * Returns a read/write reverse iterator that points to one before the
404  * first pair in the %map. Iteration is done in descending order
405  * according to the keys.
406  */
408  rend() _GLIBCXX_NOEXCEPT
409  { return _M_t.rend(); }
410 
411  /**
412  * Returns a read-only (constant) reverse iterator that points to one
413  * before the first pair in the %map. Iteration is done in descending
414  * order according to the keys.
415  */
416  const_reverse_iterator
417  rend() const _GLIBCXX_NOEXCEPT
418  { return _M_t.rend(); }
419 
420 #if __cplusplus >= 201103L
421  /**
422  * Returns a read-only (constant) iterator that points to the first pair
423  * in the %map. Iteration is done in ascending order according to the
424  * keys.
425  */
426  const_iterator
427  cbegin() const noexcept
428  { return _M_t.begin(); }
429 
430  /**
431  * Returns a read-only (constant) iterator that points one past the last
432  * pair in the %map. Iteration is done in ascending order according to
433  * the keys.
434  */
435  const_iterator
436  cend() const noexcept
437  { return _M_t.end(); }
438 
439  /**
440  * Returns a read-only (constant) reverse iterator that points to the
441  * last pair in the %map. Iteration is done in descending order
442  * according to the keys.
443  */
444  const_reverse_iterator
445  crbegin() const noexcept
446  { return _M_t.rbegin(); }
447 
448  /**
449  * Returns a read-only (constant) reverse iterator that points to one
450  * before the first pair in the %map. Iteration is done in descending
451  * order according to the keys.
452  */
453  const_reverse_iterator
454  crend() const noexcept
455  { return _M_t.rend(); }
456 #endif
457 
458  // capacity
459  /** Returns true if the %map is empty. (Thus begin() would equal
460  * end().)
461  */
462  bool
463  empty() const _GLIBCXX_NOEXCEPT
464  { return _M_t.empty(); }
465 
466  /** Returns the size of the %map. */
467  size_type
468  size() const _GLIBCXX_NOEXCEPT
469  { return _M_t.size(); }
470 
471  /** Returns the maximum size of the %map. */
472  size_type
473  max_size() const _GLIBCXX_NOEXCEPT
474  { return _M_t.max_size(); }
475 
476  // [23.3.1.2] element access
477  /**
478  * @brief Subscript ( @c [] ) access to %map data.
479  * @param __k The key for which data should be retrieved.
480  * @return A reference to the data of the (key,data) %pair.
481  *
482  * Allows for easy lookup with the subscript ( @c [] )
483  * operator. Returns data associated with the key specified in
484  * subscript. If the key does not exist, a pair with that key
485  * is created using default values, which is then returned.
486  *
487  * Lookup requires logarithmic time.
488  */
489  mapped_type&
490  operator[](const key_type& __k)
491  {
492  // concept requirements
493  __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
494 
495  iterator __i = lower_bound(__k);
496  // __i->first is greater than or equivalent to __k.
497  if (__i == end() || key_comp()(__k, (*__i).first))
498 #if __cplusplus >= 201103L
499  __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
501  std::tuple<>());
502 #else
503  __i = insert(__i, value_type(__k, mapped_type()));
504 #endif
505  return (*__i).second;
506  }
507 
508 #if __cplusplus >= 201103L
509  mapped_type&
510  operator[](key_type&& __k)
511  {
512  // concept requirements
513  __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
514 
515  iterator __i = lower_bound(__k);
516  // __i->first is greater than or equivalent to __k.
517  if (__i == end() || key_comp()(__k, (*__i).first))
518  __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
519  std::forward_as_tuple(std::move(__k)),
520  std::tuple<>());
521  return (*__i).second;
522  }
523 #endif
524 
525  // _GLIBCXX_RESOLVE_LIB_DEFECTS
526  // DR 464. Suggestion for new member functions in standard containers.
527  /**
528  * @brief Access to %map data.
529  * @param __k The key for which data should be retrieved.
530  * @return A reference to the data whose key is equivalent to @a __k, if
531  * such a data is present in the %map.
532  * @throw std::out_of_range If no such data is present.
533  */
534  mapped_type&
535  at(const key_type& __k)
536  {
537  iterator __i = lower_bound(__k);
538  if (__i == end() || key_comp()(__k, (*__i).first))
539  __throw_out_of_range(__N("map::at"));
540  return (*__i).second;
541  }
542 
543  const mapped_type&
544  at(const key_type& __k) const
545  {
546  const_iterator __i = lower_bound(__k);
547  if (__i == end() || key_comp()(__k, (*__i).first))
548  __throw_out_of_range(__N("map::at"));
549  return (*__i).second;
550  }
551 
552  // modifiers
553 #if __cplusplus >= 201103L
554  /**
555  * @brief Attempts to build and insert a std::pair into the %map.
556  *
557  * @param __args Arguments used to generate a new pair instance (see
558  * std::piecewise_contruct for passing arguments to each
559  * part of the pair constructor).
560  *
561  * @return A pair, of which the first element is an iterator that points
562  * to the possibly inserted pair, and the second is a bool that
563  * is true if the pair was actually inserted.
564  *
565  * This function attempts to build and insert a (key, value) %pair into
566  * the %map.
567  * A %map relies on unique keys and thus a %pair is only inserted if its
568  * first element (the key) is not already present in the %map.
569  *
570  * Insertion requires logarithmic time.
571  */
572  template<typename... _Args>
574  emplace(_Args&&... __args)
575  { return _M_t._M_emplace_unique(std::forward<_Args>(__args)...); }
576 
577  /**
578  * @brief Attempts to build and insert a std::pair into the %map.
579  *
580  * @param __pos An iterator that serves as a hint as to where the pair
581  * should be inserted.
582  * @param __args Arguments used to generate a new pair instance (see
583  * std::piecewise_contruct for passing arguments to each
584  * part of the pair constructor).
585  * @return An iterator that points to the element with key of the
586  * std::pair built from @a __args (may or may not be that
587  * std::pair).
588  *
589  * This function is not concerned about whether the insertion took place,
590  * and thus does not return a boolean like the single-argument emplace()
591  * does.
592  * Note that the first parameter is only a hint and can potentially
593  * improve the performance of the insertion process. A bad hint would
594  * cause no gains in efficiency.
595  *
596  * See
597  * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
598  * for more on @a hinting.
599  *
600  * Insertion requires logarithmic time (if the hint is not taken).
601  */
602  template<typename... _Args>
603  iterator
604  emplace_hint(const_iterator __pos, _Args&&... __args)
605  {
606  return _M_t._M_emplace_hint_unique(__pos,
607  std::forward<_Args>(__args)...);
608  }
609 #endif
610 
611 #if __cplusplus > 201402L
612  /// Extract a node.
613  node_type
614  extract(const_iterator __pos)
615  {
616  __glibcxx_assert(__pos != end());
617  return _M_t.extract(__pos);
618  }
619 
620  /// Extract a node.
621  node_type
622  extract(const key_type& __x)
623  { return _M_t.extract(__x); }
624 
625  /// Re-insert an extracted node.
626  insert_return_type
627  insert(node_type&& __nh)
628  { return _M_t._M_reinsert_node_unique(std::move(__nh)); }
629 
630  /// Re-insert an extracted node.
631  iterator
632  insert(const_iterator __hint, node_type&& __nh)
633  { return _M_t._M_reinsert_node_hint_unique(__hint, std::move(__nh)); }
634 
635  template<typename, typename>
636  friend class std::_Rb_tree_merge_helper;
637 
638  template<typename _C2>
639  void
640  merge(map<_Key, _Tp, _C2, _Alloc>& __source)
641  {
642  using _Merge_helper = _Rb_tree_merge_helper<map, _C2>;
643  _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
644  }
645 
646  template<typename _C2>
647  void
648  merge(map<_Key, _Tp, _C2, _Alloc>&& __source)
649  { merge(__source); }
650 
651  template<typename _C2>
652  void
653  merge(multimap<_Key, _Tp, _C2, _Alloc>& __source)
654  {
655  using _Merge_helper = _Rb_tree_merge_helper<map, _C2>;
656  _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
657  }
658 
659  template<typename _C2>
660  void
661  merge(multimap<_Key, _Tp, _C2, _Alloc>&& __source)
662  { merge(__source); }
663 #endif // C++17
664 
665 #if __cplusplus > 201402L
666 #define __cpp_lib_map_try_emplace 201411
667  /**
668  * @brief Attempts to build and insert a std::pair into the %map.
669  *
670  * @param __k Key to use for finding a possibly existing pair in
671  * the map.
672  * @param __args Arguments used to generate the .second for a new pair
673  * instance.
674  *
675  * @return A pair, of which the first element is an iterator that points
676  * to the possibly inserted pair, and the second is a bool that
677  * is true if the pair was actually inserted.
678  *
679  * This function attempts to build and insert a (key, value) %pair into
680  * the %map.
681  * A %map relies on unique keys and thus a %pair is only inserted if its
682  * first element (the key) is not already present in the %map.
683  * If a %pair is not inserted, this function has no effect.
684  *
685  * Insertion requires logarithmic time.
686  */
687  template <typename... _Args>
688  pair<iterator, bool>
689  try_emplace(const key_type& __k, _Args&&... __args)
690  {
691  iterator __i = lower_bound(__k);
692  if (__i == end() || key_comp()(__k, (*__i).first))
693  {
695  std::forward_as_tuple(__k),
696  std::forward_as_tuple(
697  std::forward<_Args>(__args)...));
698  return {__i, true};
699  }
700  return {__i, false};
701  }
702 
703  // move-capable overload
704  template <typename... _Args>
705  pair<iterator, bool>
706  try_emplace(key_type&& __k, _Args&&... __args)
707  {
708  iterator __i = lower_bound(__k);
709  if (__i == end() || key_comp()(__k, (*__i).first))
710  {
712  std::forward_as_tuple(std::move(__k)),
713  std::forward_as_tuple(
714  std::forward<_Args>(__args)...));
715  return {__i, true};
716  }
717  return {__i, false};
718  }
719 
720  /**
721  * @brief Attempts to build and insert a std::pair into the %map.
722  *
723  * @param __hint An iterator that serves as a hint as to where the
724  * pair should be inserted.
725  * @param __k Key to use for finding a possibly existing pair in
726  * the map.
727  * @param __args Arguments used to generate the .second for a new pair
728  * instance.
729  * @return An iterator that points to the element with key of the
730  * std::pair built from @a __args (may or may not be that
731  * std::pair).
732  *
733  * This function is not concerned about whether the insertion took place,
734  * and thus does not return a boolean like the single-argument
735  * try_emplace() does. However, if insertion did not take place,
736  * this function has no effect.
737  * Note that the first parameter is only a hint and can potentially
738  * improve the performance of the insertion process. A bad hint would
739  * cause no gains in efficiency.
740  *
741  * See
742  * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
743  * for more on @a hinting.
744  *
745  * Insertion requires logarithmic time (if the hint is not taken).
746  */
747  template <typename... _Args>
748  iterator
749  try_emplace(const_iterator __hint, const key_type& __k,
750  _Args&&... __args)
751  {
752  iterator __i;
753  auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
754  if (__true_hint.second)
755  __i = emplace_hint(iterator(__true_hint.second),
757  std::forward_as_tuple(__k),
758  std::forward_as_tuple(
759  std::forward<_Args>(__args)...));
760  else
761  __i = iterator(__true_hint.first);
762  return __i;
763  }
764 
765  // move-capable overload
766  template <typename... _Args>
767  iterator
768  try_emplace(const_iterator __hint, key_type&& __k, _Args&&... __args)
769  {
770  iterator __i;
771  auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
772  if (__true_hint.second)
773  __i = emplace_hint(iterator(__true_hint.second),
775  std::forward_as_tuple(std::move(__k)),
776  std::forward_as_tuple(
777  std::forward<_Args>(__args)...));
778  else
779  __i = iterator(__true_hint.first);
780  return __i;
781  }
782 #endif
783 
784  /**
785  * @brief Attempts to insert a std::pair into the %map.
786  * @param __x Pair to be inserted (see std::make_pair for easy
787  * creation of pairs).
788  *
789  * @return A pair, of which the first element is an iterator that
790  * points to the possibly inserted pair, and the second is
791  * a bool that is true if the pair was actually inserted.
792  *
793  * This function attempts to insert a (key, value) %pair into the %map.
794  * A %map relies on unique keys and thus a %pair is only inserted if its
795  * first element (the key) is not already present in the %map.
796  *
797  * Insertion requires logarithmic time.
798  * @{
799  */
801  insert(const value_type& __x)
802  { return _M_t._M_insert_unique(__x); }
803 
804 #if __cplusplus >= 201103L
805  // _GLIBCXX_RESOLVE_LIB_DEFECTS
806  // 2354. Unnecessary copying when inserting into maps with braced-init
809  { return _M_t._M_insert_unique(std::move(__x)); }
810 
811  template<typename _Pair, typename = typename
813  _Pair&&>::value>::type>
815  insert(_Pair&& __x)
816  { return _M_t._M_insert_unique(std::forward<_Pair>(__x)); }
817 #endif
818  // @}
819 
820 #if __cplusplus >= 201103L
821  /**
822  * @brief Attempts to insert a list of std::pairs into the %map.
823  * @param __list A std::initializer_list<value_type> of pairs to be
824  * inserted.
825  *
826  * Complexity similar to that of the range constructor.
827  */
828  void
830  { insert(__list.begin(), __list.end()); }
831 #endif
832 
833  /**
834  * @brief Attempts to insert a std::pair into the %map.
835  * @param __position An iterator that serves as a hint as to where the
836  * pair should be inserted.
837  * @param __x Pair to be inserted (see std::make_pair for easy creation
838  * of pairs).
839  * @return An iterator that points to the element with key of
840  * @a __x (may or may not be the %pair passed in).
841  *
842 
843  * This function is not concerned about whether the insertion
844  * took place, and thus does not return a boolean like the
845  * single-argument insert() does. Note that the first
846  * parameter is only a hint and can potentially improve the
847  * performance of the insertion process. A bad hint would
848  * cause no gains in efficiency.
849  *
850  * See
851  * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
852  * for more on @a hinting.
853  *
854  * Insertion requires logarithmic time (if the hint is not taken).
855  * @{
856  */
857  iterator
858 #if __cplusplus >= 201103L
859  insert(const_iterator __position, const value_type& __x)
860 #else
861  insert(iterator __position, const value_type& __x)
862 #endif
863  { return _M_t._M_insert_unique_(__position, __x); }
864 
865 #if __cplusplus >= 201103L
866  // _GLIBCXX_RESOLVE_LIB_DEFECTS
867  // 2354. Unnecessary copying when inserting into maps with braced-init
868  iterator
869  insert(const_iterator __position, value_type&& __x)
870  { return _M_t._M_insert_unique_(__position, std::move(__x)); }
871 
872  template<typename _Pair, typename = typename
874  _Pair&&>::value>::type>
875  iterator
876  insert(const_iterator __position, _Pair&& __x)
877  { return _M_t._M_insert_unique_(__position,
878  std::forward<_Pair>(__x)); }
879 #endif
880  // @}
881 
882  /**
883  * @brief Template function that attempts to insert a range of elements.
884  * @param __first Iterator pointing to the start of the range to be
885  * inserted.
886  * @param __last Iterator pointing to the end of the range.
887  *
888  * Complexity similar to that of the range constructor.
889  */
890  template<typename _InputIterator>
891  void
892  insert(_InputIterator __first, _InputIterator __last)
893  { _M_t._M_insert_unique(__first, __last); }
894 
895 #if __cplusplus > 201402L
896 #define __cpp_lib_map_insertion 201411
897  /**
898  * @brief Attempts to insert or assign a std::pair into the %map.
899  * @param __k Key to use for finding a possibly existing pair in
900  * the map.
901  * @param __obj Argument used to generate the .second for a pair
902  * instance.
903  *
904  * @return A pair, of which the first element is an iterator that
905  * points to the possibly inserted pair, and the second is
906  * a bool that is true if the pair was actually inserted.
907  *
908  * This function attempts to insert a (key, value) %pair into the %map.
909  * A %map relies on unique keys and thus a %pair is only inserted if its
910  * first element (the key) is not already present in the %map.
911  * If the %pair was already in the %map, the .second of the %pair
912  * is assigned from __obj.
913  *
914  * Insertion requires logarithmic time.
915  */
916  template <typename _Obj>
918  insert_or_assign(const key_type& __k, _Obj&& __obj)
919  {
920  iterator __i = lower_bound(__k);
921  if (__i == end() || key_comp()(__k, (*__i).first))
922  {
924  std::forward_as_tuple(__k),
925  std::forward_as_tuple(
926  std::forward<_Obj>(__obj)));
927  return {__i, true};
928  }
929  (*__i).second = std::forward<_Obj>(__obj);
930  return {__i, false};
931  }
932 
933  // move-capable overload
934  template <typename _Obj>
935  pair<iterator, bool>
936  insert_or_assign(key_type&& __k, _Obj&& __obj)
937  {
938  iterator __i = lower_bound(__k);
939  if (__i == end() || key_comp()(__k, (*__i).first))
940  {
942  std::forward_as_tuple(std::move(__k)),
943  std::forward_as_tuple(
944  std::forward<_Obj>(__obj)));
945  return {__i, true};
946  }
947  (*__i).second = std::forward<_Obj>(__obj);
948  return {__i, false};
949  }
950 
951  /**
952  * @brief Attempts to insert or assign a std::pair into the %map.
953  * @param __hint An iterator that serves as a hint as to where the
954  * pair should be inserted.
955  * @param __k Key to use for finding a possibly existing pair in
956  * the map.
957  * @param __obj Argument used to generate the .second for a pair
958  * instance.
959  *
960  * @return An iterator that points to the element with key of
961  * @a __x (may or may not be the %pair passed in).
962  *
963  * This function attempts to insert a (key, value) %pair into the %map.
964  * A %map relies on unique keys and thus a %pair is only inserted if its
965  * first element (the key) is not already present in the %map.
966  * If the %pair was already in the %map, the .second of the %pair
967  * is assigned from __obj.
968  *
969  * Insertion requires logarithmic time.
970  */
971  template <typename _Obj>
972  iterator
973  insert_or_assign(const_iterator __hint,
974  const key_type& __k, _Obj&& __obj)
975  {
976  iterator __i;
977  auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
978  if (__true_hint.second)
979  {
980  return emplace_hint(iterator(__true_hint.second),
982  std::forward_as_tuple(__k),
983  std::forward_as_tuple(
984  std::forward<_Obj>(__obj)));
985  }
986  __i = iterator(__true_hint.first);
987  (*__i).second = std::forward<_Obj>(__obj);
988  return __i;
989  }
990 
991  // move-capable overload
992  template <typename _Obj>
993  iterator
994  insert_or_assign(const_iterator __hint, key_type&& __k, _Obj&& __obj)
995  {
996  iterator __i;
997  auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
998  if (__true_hint.second)
999  {
1000  return emplace_hint(iterator(__true_hint.second),
1002  std::forward_as_tuple(std::move(__k)),
1003  std::forward_as_tuple(
1004  std::forward<_Obj>(__obj)));
1005  }
1006  __i = iterator(__true_hint.first);
1007  (*__i).second = std::forward<_Obj>(__obj);
1008  return __i;
1009  }
1010 #endif
1011 
1012 #if __cplusplus >= 201103L
1013  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1014  // DR 130. Associative erase should return an iterator.
1015  /**
1016  * @brief Erases an element from a %map.
1017  * @param __position An iterator pointing to the element to be erased.
1018  * @return An iterator pointing to the element immediately following
1019  * @a position prior to the element being erased. If no such
1020  * element exists, end() is returned.
1021  *
1022  * This function erases an element, pointed to by the given
1023  * iterator, from a %map. Note that this function only erases
1024  * the element, and that if the element is itself a pointer,
1025  * the pointed-to memory is not touched in any way. Managing
1026  * the pointer is the user's responsibility.
1027  *
1028  * @{
1029  */
1030  iterator
1031  erase(const_iterator __position)
1032  { return _M_t.erase(__position); }
1033 
1034  // LWG 2059
1035  _GLIBCXX_ABI_TAG_CXX11
1036  iterator
1037  erase(iterator __position)
1038  { return _M_t.erase(__position); }
1039  // @}
1040 #else
1041  /**
1042  * @brief Erases an element from a %map.
1043  * @param __position An iterator pointing to the element to be erased.
1044  *
1045  * This function erases an element, pointed to by the given
1046  * iterator, from a %map. Note that this function only erases
1047  * the element, and that if the element is itself a pointer,
1048  * the pointed-to memory is not touched in any way. Managing
1049  * the pointer is the user's responsibility.
1050  */
1051  void
1052  erase(iterator __position)
1053  { _M_t.erase(__position); }
1054 #endif
1055 
1056  /**
1057  * @brief Erases elements according to the provided key.
1058  * @param __x Key of element to be erased.
1059  * @return The number of elements erased.
1060  *
1061  * This function erases all the elements located by the given key from
1062  * a %map.
1063  * Note that this function only erases the element, and that if
1064  * the element is itself a pointer, the pointed-to memory is not touched
1065  * in any way. Managing the pointer is the user's responsibility.
1066  */
1067  size_type
1068  erase(const key_type& __x)
1069  { return _M_t.erase(__x); }
1070 
1071 #if __cplusplus >= 201103L
1072  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1073  // DR 130. Associative erase should return an iterator.
1074  /**
1075  * @brief Erases a [first,last) range of elements from a %map.
1076  * @param __first Iterator pointing to the start of the range to be
1077  * erased.
1078  * @param __last Iterator pointing to the end of the range to
1079  * be erased.
1080  * @return The iterator @a __last.
1081  *
1082  * This function erases a sequence of elements from a %map.
1083  * Note that this function only erases the element, and that if
1084  * the element is itself a pointer, the pointed-to memory is not touched
1085  * in any way. Managing the pointer is the user's responsibility.
1086  */
1087  iterator
1088  erase(const_iterator __first, const_iterator __last)
1089  { return _M_t.erase(__first, __last); }
1090 #else
1091  /**
1092  * @brief Erases a [__first,__last) range of elements from a %map.
1093  * @param __first Iterator pointing to the start of the range to be
1094  * erased.
1095  * @param __last Iterator pointing to the end of the range to
1096  * be erased.
1097  *
1098  * This function erases a sequence of elements from a %map.
1099  * Note that this function only erases the element, and that if
1100  * the element is itself a pointer, the pointed-to memory is not touched
1101  * in any way. Managing the pointer is the user's responsibility.
1102  */
1103  void
1104  erase(iterator __first, iterator __last)
1105  { _M_t.erase(__first, __last); }
1106 #endif
1107 
1108  /**
1109  * @brief Swaps data with another %map.
1110  * @param __x A %map of the same element and allocator types.
1111  *
1112  * This exchanges the elements between two maps in constant
1113  * time. (It is only swapping a pointer, an integer, and an
1114  * instance of the @c Compare type (which itself is often
1115  * stateless and empty), so it should be quite fast.) Note
1116  * that the global std::swap() function is specialized such
1117  * that std::swap(m1,m2) will feed to this function.
1118  *
1119  * Whether the allocators are swapped depends on the allocator traits.
1120  */
1121  void
1122  swap(map& __x)
1123  _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
1124  { _M_t.swap(__x._M_t); }
1125 
1126  /**
1127  * Erases all elements in a %map. Note that this function only
1128  * erases the elements, and that if the elements themselves are
1129  * pointers, the pointed-to memory is not touched in any way.
1130  * Managing the pointer is the user's responsibility.
1131  */
1132  void
1133  clear() _GLIBCXX_NOEXCEPT
1134  { _M_t.clear(); }
1135 
1136  // observers
1137  /**
1138  * Returns the key comparison object out of which the %map was
1139  * constructed.
1140  */
1141  key_compare
1142  key_comp() const
1143  { return _M_t.key_comp(); }
1144 
1145  /**
1146  * Returns a value comparison object, built from the key comparison
1147  * object out of which the %map was constructed.
1148  */
1149  value_compare
1150  value_comp() const
1151  { return value_compare(_M_t.key_comp()); }
1152 
1153  // [23.3.1.3] map operations
1154 
1155  //@{
1156  /**
1157  * @brief Tries to locate an element in a %map.
1158  * @param __x Key of (key, value) %pair to be located.
1159  * @return Iterator pointing to sought-after element, or end() if not
1160  * found.
1161  *
1162  * This function takes a key and tries to locate the element with which
1163  * the key matches. If successful the function returns an iterator
1164  * pointing to the sought after %pair. If unsuccessful it returns the
1165  * past-the-end ( @c end() ) iterator.
1166  */
1167 
1168  iterator
1169  find(const key_type& __x)
1170  { return _M_t.find(__x); }
1171 
1172 #if __cplusplus > 201103L
1173  template<typename _Kt>
1174  auto
1175  find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
1176  { return _M_t._M_find_tr(__x); }
1177 #endif
1178  //@}
1179 
1180  //@{
1181  /**
1182  * @brief Tries to locate an element in a %map.
1183  * @param __x Key of (key, value) %pair to be located.
1184  * @return Read-only (constant) iterator pointing to sought-after
1185  * element, or end() if not found.
1186  *
1187  * This function takes a key and tries to locate the element with which
1188  * the key matches. If successful the function returns a constant
1189  * iterator pointing to the sought after %pair. If unsuccessful it
1190  * returns the past-the-end ( @c end() ) iterator.
1191  */
1192 
1193  const_iterator
1194  find(const key_type& __x) const
1195  { return _M_t.find(__x); }
1196 
1197 #if __cplusplus > 201103L
1198  template<typename _Kt>
1199  auto
1200  find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
1201  { return _M_t._M_find_tr(__x); }
1202 #endif
1203  //@}
1204 
1205  //@{
1206  /**
1207  * @brief Finds the number of elements with given key.
1208  * @param __x Key of (key, value) pairs to be located.
1209  * @return Number of elements with specified key.
1210  *
1211  * This function only makes sense for multimaps; for map the result will
1212  * either be 0 (not present) or 1 (present).
1213  */
1214  size_type
1215  count(const key_type& __x) const
1216  { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
1217 
1218 #if __cplusplus > 201103L
1219  template<typename _Kt>
1220  auto
1221  count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
1222  { return _M_t._M_count_tr(__x); }
1223 #endif
1224  //@}
1225 
1226  //@{
1227  /**
1228  * @brief Finds the beginning of a subsequence matching given key.
1229  * @param __x Key of (key, value) pair to be located.
1230  * @return Iterator pointing to first element equal to or greater
1231  * than key, or end().
1232  *
1233  * This function returns the first element of a subsequence of elements
1234  * that matches the given key. If unsuccessful it returns an iterator
1235  * pointing to the first element that has a greater value than given key
1236  * or end() if no such element exists.
1237  */
1238  iterator
1239  lower_bound(const key_type& __x)
1240  { return _M_t.lower_bound(__x); }
1241 
1242 #if __cplusplus > 201103L
1243  template<typename _Kt>
1244  auto
1245  lower_bound(const _Kt& __x)
1246  -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
1247  { return iterator(_M_t._M_lower_bound_tr(__x)); }
1248 #endif
1249  //@}
1250 
1251  //@{
1252  /**
1253  * @brief Finds the beginning of a subsequence matching given key.
1254  * @param __x Key of (key, value) pair to be located.
1255  * @return Read-only (constant) iterator pointing to first element
1256  * equal to or greater than key, or end().
1257  *
1258  * This function returns the first element of a subsequence of elements
1259  * that matches the given key. If unsuccessful it returns an iterator
1260  * pointing to the first element that has a greater value than given key
1261  * or end() if no such element exists.
1262  */
1263  const_iterator
1264  lower_bound(const key_type& __x) const
1265  { return _M_t.lower_bound(__x); }
1266 
1267 #if __cplusplus > 201103L
1268  template<typename _Kt>
1269  auto
1270  lower_bound(const _Kt& __x) const
1271  -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
1272  { return const_iterator(_M_t._M_lower_bound_tr(__x)); }
1273 #endif
1274  //@}
1275 
1276  //@{
1277  /**
1278  * @brief Finds the end of a subsequence matching given key.
1279  * @param __x Key of (key, value) pair to be located.
1280  * @return Iterator pointing to the first element
1281  * greater than key, or end().
1282  */
1283  iterator
1284  upper_bound(const key_type& __x)
1285  { return _M_t.upper_bound(__x); }
1286 
1287 #if __cplusplus > 201103L
1288  template<typename _Kt>
1289  auto
1290  upper_bound(const _Kt& __x)
1291  -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
1292  { return iterator(_M_t._M_upper_bound_tr(__x)); }
1293 #endif
1294  //@}
1295 
1296  //@{
1297  /**
1298  * @brief Finds the end of a subsequence matching given key.
1299  * @param __x Key of (key, value) pair to be located.
1300  * @return Read-only (constant) iterator pointing to first iterator
1301  * greater than key, or end().
1302  */
1303  const_iterator
1304  upper_bound(const key_type& __x) const
1305  { return _M_t.upper_bound(__x); }
1306 
1307 #if __cplusplus > 201103L
1308  template<typename _Kt>
1309  auto
1310  upper_bound(const _Kt& __x) const
1311  -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
1312  { return const_iterator(_M_t._M_upper_bound_tr(__x)); }
1313 #endif
1314  //@}
1315 
1316  //@{
1317  /**
1318  * @brief Finds a subsequence matching given key.
1319  * @param __x Key of (key, value) pairs to be located.
1320  * @return Pair of iterators that possibly points to the subsequence
1321  * matching given key.
1322  *
1323  * This function is equivalent to
1324  * @code
1325  * std::make_pair(c.lower_bound(val),
1326  * c.upper_bound(val))
1327  * @endcode
1328  * (but is faster than making the calls separately).
1329  *
1330  * This function probably only makes sense for multimaps.
1331  */
1333  equal_range(const key_type& __x)
1334  { return _M_t.equal_range(__x); }
1335 
1336 #if __cplusplus > 201103L
1337  template<typename _Kt>
1338  auto
1339  equal_range(const _Kt& __x)
1340  -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
1341  { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
1342 #endif
1343  //@}
1344 
1345  //@{
1346  /**
1347  * @brief Finds a subsequence matching given key.
1348  * @param __x Key of (key, value) pairs to be located.
1349  * @return Pair of read-only (constant) iterators that possibly points
1350  * to the subsequence matching given key.
1351  *
1352  * This function is equivalent to
1353  * @code
1354  * std::make_pair(c.lower_bound(val),
1355  * c.upper_bound(val))
1356  * @endcode
1357  * (but is faster than making the calls separately).
1358  *
1359  * This function probably only makes sense for multimaps.
1360  */
1362  equal_range(const key_type& __x) const
1363  { return _M_t.equal_range(__x); }
1364 
1365 #if __cplusplus > 201103L
1366  template<typename _Kt>
1367  auto
1368  equal_range(const _Kt& __x) const
1370  _M_t._M_equal_range_tr(__x)))
1371  {
1373  _M_t._M_equal_range_tr(__x));
1374  }
1375 #endif
1376  //@}
1377 
1378  template<typename _K1, typename _T1, typename _C1, typename _A1>
1379  friend bool
1380  operator==(const map<_K1, _T1, _C1, _A1>&,
1381  const map<_K1, _T1, _C1, _A1>&);
1382 
1383  template<typename _K1, typename _T1, typename _C1, typename _A1>
1384  friend bool
1385  operator<(const map<_K1, _T1, _C1, _A1>&,
1386  const map<_K1, _T1, _C1, _A1>&);
1387  };
1388 
1389 
1390 #if __cpp_deduction_guides >= 201606
1391 
1392  template<typename _InputIterator,
1393  typename _Compare = less<__iter_key_t<_InputIterator>>,
1394  typename _Allocator = allocator<__iter_to_alloc_t<_InputIterator>>,
1395  typename = _RequireInputIter<_InputIterator>,
1396  typename = _RequireAllocator<_Allocator>>
1397  map(_InputIterator, _InputIterator,
1398  _Compare = _Compare(), _Allocator = _Allocator())
1399  -> map<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1400  _Compare, _Allocator>;
1401 
1402  template<typename _Key, typename _Tp, typename _Compare = less<_Key>,
1403  typename _Allocator = allocator<pair<const _Key, _Tp>>,
1404  typename = _RequireAllocator<_Allocator>>
1405  map(initializer_list<pair<_Key, _Tp>>,
1406  _Compare = _Compare(), _Allocator = _Allocator())
1407  -> map<_Key, _Tp, _Compare, _Allocator>;
1408 
1409  template <typename _InputIterator, typename _Allocator,
1410  typename = _RequireInputIter<_InputIterator>,
1411  typename = _RequireAllocator<_Allocator>>
1412  map(_InputIterator, _InputIterator, _Allocator)
1413  -> map<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1414  less<__iter_key_t<_InputIterator>>, _Allocator>;
1415 
1416  template<typename _Key, typename _Tp, typename _Allocator,
1417  typename = _RequireAllocator<_Allocator>>
1418  map(initializer_list<pair<_Key, _Tp>>, _Allocator)
1419  -> map<_Key, _Tp, less<_Key>, _Allocator>;
1420 
1421 #endif
1422 
1423  /**
1424  * @brief Map equality comparison.
1425  * @param __x A %map.
1426  * @param __y A %map of the same type as @a x.
1427  * @return True iff the size and elements of the maps are equal.
1428  *
1429  * This is an equivalence relation. It is linear in the size of the
1430  * maps. Maps are considered equivalent if their sizes are equal,
1431  * and if corresponding elements compare equal.
1432  */
1433  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1434  inline bool
1435  operator==(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1437  { return __x._M_t == __y._M_t; }
1438 
1439  /**
1440  * @brief Map ordering relation.
1441  * @param __x A %map.
1442  * @param __y A %map of the same type as @a x.
1443  * @return True iff @a x is lexicographically less than @a y.
1444  *
1445  * This is a total ordering relation. It is linear in the size of the
1446  * maps. The elements must be comparable with @c <.
1447  *
1448  * See std::lexicographical_compare() for how the determination is made.
1449  */
1450  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1451  inline bool
1452  operator<(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1454  { return __x._M_t < __y._M_t; }
1455 
1456  /// Based on operator==
1457  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1458  inline bool
1459  operator!=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1461  { return !(__x == __y); }
1462 
1463  /// Based on operator<
1464  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1465  inline bool
1466  operator>(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1468  { return __y < __x; }
1469 
1470  /// Based on operator<
1471  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1472  inline bool
1473  operator<=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1475  { return !(__y < __x); }
1476 
1477  /// Based on operator<
1478  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1479  inline bool
1480  operator>=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1482  { return !(__x < __y); }
1483 
1484  /// See std::map::swap().
1485  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1486  inline void
1489  _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
1490  { __x.swap(__y); }
1491 
1492 _GLIBCXX_END_NAMESPACE_CONTAINER
1493 
1494 #if __cplusplus > 201402L
1495  // Allow std::map access to internals of compatible maps.
1496  template<typename _Key, typename _Val, typename _Cmp1, typename _Alloc,
1497  typename _Cmp2>
1498  struct
1499  _Rb_tree_merge_helper<_GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>,
1500  _Cmp2>
1501  {
1502  private:
1503  friend class _GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>;
1504 
1505  static auto&
1506  _S_get_tree(_GLIBCXX_STD_C::map<_Key, _Val, _Cmp2, _Alloc>& __map)
1507  { return __map._M_t; }
1508 
1509  static auto&
1510  _S_get_tree(_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp2, _Alloc>& __map)
1511  { return __map._M_t; }
1512  };
1513 #endif // C++17
1514 
1515 _GLIBCXX_END_NAMESPACE_VERSION
1516 } // namespace std
1517 
1518 #endif /* _STL_MAP_H */
is_same
Definition: type_traits:1339
const_reverse_iterator rbegin() const noexcept
Definition: stl_map.h:399
const_reverse_iterator crend() const noexcept
Definition: stl_map.h:454
mapped_type & operator[](const key_type &__k)
Subscript ( [] ) access to map data.
Definition: stl_map.h:490
Primary class template, tuple.
Definition: tuple:53
map(const _Compare &__comp, const allocator_type &__a=allocator_type())
Creates a map with no elements.
Definition: stl_map.h:192
std::pair< iterator, bool > insert(value_type &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:808
iterator begin() noexcept
Definition: stl_map.h:354
Define a member typedef type only if a boolean constant is true.
Definition: type_traits:1987
_GLIBCXX_ABI_TAG_CXX11 iterator erase(iterator __position)
Erases an element from a map.
Definition: stl_map.h:1037
auto upper_bound(const _Kt &__x) const -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
Finds the end of a subsequence matching given key.
Definition: stl_map.h:1310
iterator erase(const_iterator __position)
Erases an element from a map.
Definition: stl_map.h:1031
auto find(const _Kt &__x) const -> decltype(_M_t._M_find_tr(__x))
Tries to locate an element in a map.
Definition: stl_map.h:1200
std::pair< iterator, iterator > equal_range(const key_type &__x)
Finds a subsequence matching given key.
Definition: stl_map.h:1333
auto count(const _Kt &__x) const -> decltype(_M_t._M_count_tr(__x))
Finds the number of elements with given key.
Definition: stl_map.h:1221
auto equal_range(const _Kt &__x) -> decltype(pair< iterator, iterator >(_M_t._M_equal_range_tr(__x)))
Finds a subsequence matching given key.
Definition: stl_map.h:1339
key_compare key_comp() const
Definition: stl_map.h:1142
auto upper_bound(const _Kt &__x) -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
Finds the end of a subsequence matching given key.
Definition: stl_map.h:1290
const_iterator lower_bound(const key_type &__x) const
Finds the beginning of a subsequence matching given key.
Definition: stl_map.h:1264
A standard container made up of (key,value) pairs, which can be retrieved based on a key...
Definition: stl_map.h:100
iterator end() noexcept
Definition: stl_map.h:372
is_nothrow_copy_constructible
Definition: type_traits:1036
_T1 first
second_type is the second bound type
Definition: stl_pair.h:203
~map()=default
reverse_iterator rbegin() noexcept
Definition: stl_map.h:390
std::pair< iterator, bool > emplace(_Args &&... __args)
Attempts to build and insert a std::pair into the map.
Definition: stl_map.h:574
allocator_type get_allocator() const noexcept
Get a copy of the memory allocation object.
Definition: stl_map.h:344
std::pair< iterator, bool > insert(_Pair &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:815
void insert(std::initializer_list< value_type > __list)
Attempts to insert a list of std::pairs into the map.
Definition: stl_map.h:829
map(_InputIterator __first, _InputIterator __last, const allocator_type &__a)
Allocator-extended range constructor.
Definition: stl_map.h:254
void swap(map &__x) noexcept(/*conditional */)
Swaps data with another map.
Definition: stl_map.h:1122
value_compare value_comp() const
Definition: stl_map.h:1150
iterator erase(const_iterator __first, const_iterator __last)
Erases a [first,last) range of elements from a map.
Definition: stl_map.h:1088
map(const allocator_type &__a)
Allocator-extended default constructor.
Definition: stl_map.h:234
size_type size() const noexcept
Definition: stl_map.h:468
map()=default
Default constructor creates no elements.
const_iterator end() const noexcept
Definition: stl_map.h:381
_GLIBCXX17_INLINE constexpr piecewise_construct_t piecewise_construct
piecewise_construct
Definition: stl_pair.h:79
ISO C++ entities toplevel namespace is std.
Uniform interface to C++98 and C++11 allocators.
auto find(const _Kt &__x) -> decltype(_M_t._M_find_tr(__x))
Tries to locate an element in a map.
Definition: stl_map.h:1175
const_reverse_iterator crbegin() const noexcept
Definition: stl_map.h:445
is_constructible
Definition: type_traits:932
iterator emplace_hint(const_iterator __pos, _Args &&... __args)
Attempts to build and insert a std::pair into the map.
Definition: stl_map.h:604
map(_InputIterator __first, _InputIterator __last, const _Compare &__comp, const allocator_type &__a=allocator_type())
Builds a map from a range.
Definition: stl_map.h:288
std::pair< const_iterator, const_iterator > equal_range(const key_type &__x) const
Finds a subsequence matching given key.
Definition: stl_map.h:1362
auto lower_bound(const _Kt &__x) -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
Finds the beginning of a subsequence matching given key.
Definition: stl_map.h:1245
const_reverse_iterator rend() const noexcept
Definition: stl_map.h:417
const_iterator cend() const noexcept
Definition: stl_map.h:436
map & operator=(const map &)=default
Map assignment operator.
map(initializer_list< value_type > __l, const _Compare &__comp=_Compare(), const allocator_type &__a=allocator_type())
Builds a map from an initializer_list.
Definition: stl_map.h:226
void clear() noexcept
Definition: stl_map.h:1133
reverse_iterator rend() noexcept
Definition: stl_map.h:408
A standard container made up of (key,value) pairs, which can be retrieved based on a key...
Definition: stl_map.h:72
map & operator=(initializer_list< value_type > __l)
Map list assignment operator.
Definition: stl_map.h:335
const_iterator upper_bound(const key_type &__x) const
Finds the end of a subsequence matching given key.
Definition: stl_map.h:1304
iterator insert(const_iterator __position, value_type &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:869
iterator insert(const_iterator __position, _Pair &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:876
size_type count(const key_type &__x) const
Finds the number of elements with given key.
Definition: stl_map.h:1215
auto equal_range(const _Kt &__x) const -> decltype(pair< const_iterator, const_iterator >(_M_t._M_equal_range_tr(__x)))
Finds a subsequence matching given key.
Definition: stl_map.h:1368
const_iterator cbegin() const noexcept
Definition: stl_map.h:427
initializer_list
size_type max_size() const noexcept
Definition: stl_map.h:473
iterator insert(const_iterator __position, const value_type &__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:859
Common iterator class.
auto lower_bound(const _Kt &__x) const -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
Finds the beginning of a subsequence matching given key.
Definition: stl_map.h:1270
const_iterator find(const key_type &__x) const
Tries to locate an element in a map.
Definition: stl_map.h:1194
size_type erase(const key_type &__x)
Erases elements according to the provided key.
Definition: stl_map.h:1068
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:198
map(initializer_list< value_type > __l, const allocator_type &__a)
Allocator-extended initialier-list constructor.
Definition: stl_map.h:248
mapped_type & at(const key_type &__k)
Access to map data.
Definition: stl_map.h:535
map(_InputIterator __first, _InputIterator __last)
Builds a map from a range.
Definition: stl_map.h:271
std::pair< iterator, bool > insert(const value_type &__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:801
iterator find(const key_type &__x)
Tries to locate an element in a map.
Definition: stl_map.h:1169
map(const map &__m, const allocator_type &__a)
Allocator-extended copy constructor.
Definition: stl_map.h:238
iterator upper_bound(const key_type &__x)
Finds the end of a subsequence matching given key.
Definition: stl_map.h:1284
bool empty() const noexcept
Definition: stl_map.h:463
map(map &&__m, const allocator_type &__a) noexcept(is_nothrow_copy_constructible< _Compare >::value &&_Alloc_traits::_S_always_equal())
Allocator-extended move constructor.
Definition: stl_map.h:242
const_iterator begin() const noexcept
Definition: stl_map.h:363
void insert(_InputIterator __first, _InputIterator __last)
Template function that attempts to insert a range of elements.
Definition: stl_map.h:892
iterator lower_bound(const key_type &__x)
Finds the beginning of a subsequence matching given key.
Definition: stl_map.h:1239