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
122 #if __cplusplus > 201703L || defined __STRICT_ANSI__
124  "std::map must have the same value_type as its allocator");
125 #endif
126 #endif
127 
128  public:
129  class value_compare
130  : public std::binary_function<value_type, value_type, bool>
131  {
132  friend class map<_Key, _Tp, _Compare, _Alloc>;
133  protected:
134  _Compare comp;
135 
136  value_compare(_Compare __c)
137  : comp(__c) { }
138 
139  public:
140  bool operator()(const value_type& __x, const value_type& __y) const
141  { return comp(__x.first, __y.first); }
142  };
143 
144  private:
145  /// This turns a red-black tree into a [multi]map.
147  rebind<value_type>::other _Pair_alloc_type;
148 
149  typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
150  key_compare, _Pair_alloc_type> _Rep_type;
151 
152  /// The actual tree structure.
153  _Rep_type _M_t;
154 
156 
157  public:
158  // many of these are specified differently in ISO, but the following are
159  // "functionally equivalent"
160  typedef typename _Alloc_traits::pointer pointer;
161  typedef typename _Alloc_traits::const_pointer const_pointer;
162  typedef typename _Alloc_traits::reference reference;
163  typedef typename _Alloc_traits::const_reference const_reference;
164  typedef typename _Rep_type::iterator iterator;
165  typedef typename _Rep_type::const_iterator const_iterator;
166  typedef typename _Rep_type::size_type size_type;
167  typedef typename _Rep_type::difference_type difference_type;
170 
171 #if __cplusplus > 201402L
172  using node_type = typename _Rep_type::node_type;
173  using insert_return_type = typename _Rep_type::insert_return_type;
174 #endif
175 
176  // [23.3.1.1] construct/copy/destroy
177  // (get_allocator() is also listed in this section)
178 
179  /**
180  * @brief Default constructor creates no elements.
181  */
182 #if __cplusplus < 201103L
183  map() : _M_t() { }
184 #else
185  map() = default;
186 #endif
187 
188  /**
189  * @brief Creates a %map with no elements.
190  * @param __comp A comparison object.
191  * @param __a An allocator object.
192  */
193  explicit
194  map(const _Compare& __comp,
195  const allocator_type& __a = allocator_type())
196  : _M_t(__comp, _Pair_alloc_type(__a)) { }
197 
198  /**
199  * @brief %Map copy constructor.
200  *
201  * Whether the allocator is copied depends on the allocator traits.
202  */
203 #if __cplusplus < 201103L
204  map(const map& __x)
205  : _M_t(__x._M_t) { }
206 #else
207  map(const map&) = default;
208 
209  /**
210  * @brief %Map move constructor.
211  *
212  * The newly-created %map contains the exact contents of the moved
213  * instance. The moved instance is a valid, but unspecified, %map.
214  */
215  map(map&&) = default;
216 
217  /**
218  * @brief Builds a %map from an initializer_list.
219  * @param __l An initializer_list.
220  * @param __comp A comparison object.
221  * @param __a An allocator object.
222  *
223  * Create a %map consisting of copies of the elements in the
224  * initializer_list @a __l.
225  * This is linear in N if the range is already sorted, and NlogN
226  * otherwise (where N is @a __l.size()).
227  */
229  const _Compare& __comp = _Compare(),
230  const allocator_type& __a = allocator_type())
231  : _M_t(__comp, _Pair_alloc_type(__a))
232  { _M_t._M_insert_range_unique(__l.begin(), __l.end()); }
233 
234  /// Allocator-extended default constructor.
235  explicit
236  map(const allocator_type& __a)
237  : _M_t(_Pair_alloc_type(__a)) { }
238 
239  /// Allocator-extended copy constructor.
240  map(const map& __m, const allocator_type& __a)
241  : _M_t(__m._M_t, _Pair_alloc_type(__a)) { }
242 
243  /// Allocator-extended move constructor.
244  map(map&& __m, const allocator_type& __a)
246  && _Alloc_traits::_S_always_equal())
247  : _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { }
248 
249  /// Allocator-extended initialier-list constructor.
250  map(initializer_list<value_type> __l, const allocator_type& __a)
251  : _M_t(_Pair_alloc_type(__a))
252  { _M_t._M_insert_range_unique(__l.begin(), __l.end()); }
253 
254  /// Allocator-extended range constructor.
255  template<typename _InputIterator>
256  map(_InputIterator __first, _InputIterator __last,
257  const allocator_type& __a)
258  : _M_t(_Pair_alloc_type(__a))
259  { _M_t._M_insert_range_unique(__first, __last); }
260 #endif
261 
262  /**
263  * @brief Builds a %map from a range.
264  * @param __first An input iterator.
265  * @param __last An input iterator.
266  *
267  * Create a %map consisting of copies of the elements from
268  * [__first,__last). This is linear in N if the range is
269  * already sorted, and NlogN otherwise (where N is
270  * distance(__first,__last)).
271  */
272  template<typename _InputIterator>
273  map(_InputIterator __first, _InputIterator __last)
274  : _M_t()
275  { _M_t._M_insert_range_unique(__first, __last); }
276 
277  /**
278  * @brief Builds a %map from a range.
279  * @param __first An input iterator.
280  * @param __last An input iterator.
281  * @param __comp A comparison functor.
282  * @param __a An allocator object.
283  *
284  * Create a %map consisting of copies of the elements from
285  * [__first,__last). This is linear in N if the range is
286  * already sorted, and NlogN otherwise (where N is
287  * distance(__first,__last)).
288  */
289  template<typename _InputIterator>
290  map(_InputIterator __first, _InputIterator __last,
291  const _Compare& __comp,
292  const allocator_type& __a = allocator_type())
293  : _M_t(__comp, _Pair_alloc_type(__a))
294  { _M_t._M_insert_range_unique(__first, __last); }
295 
296 #if __cplusplus >= 201103L
297  /**
298  * The dtor only erases the elements, and note that if the elements
299  * themselves are pointers, the pointed-to memory is not touched in any
300  * way. Managing the pointer is the user's responsibility.
301  */
302  ~map() = default;
303 #endif
304 
305  /**
306  * @brief %Map assignment operator.
307  *
308  * Whether the allocator is copied depends on the allocator traits.
309  */
310 #if __cplusplus < 201103L
311  map&
312  operator=(const map& __x)
313  {
314  _M_t = __x._M_t;
315  return *this;
316  }
317 #else
318  map&
319  operator=(const map&) = default;
320 
321  /// Move assignment operator.
322  map&
323  operator=(map&&) = default;
324 
325  /**
326  * @brief %Map list assignment operator.
327  * @param __l An initializer_list.
328  *
329  * This function fills a %map with copies of the elements in the
330  * initializer list @a __l.
331  *
332  * Note that the assignment completely changes the %map and
333  * that the resulting %map's size is the same as the number
334  * of elements assigned.
335  */
336  map&
338  {
339  _M_t._M_assign_unique(__l.begin(), __l.end());
340  return *this;
341  }
342 #endif
343 
344  /// Get a copy of the memory allocation object.
345  allocator_type
346  get_allocator() const _GLIBCXX_NOEXCEPT
347  { return allocator_type(_M_t.get_allocator()); }
348 
349  // iterators
350  /**
351  * Returns a read/write iterator that points to the first pair in the
352  * %map.
353  * Iteration is done in ascending order according to the keys.
354  */
355  iterator
356  begin() _GLIBCXX_NOEXCEPT
357  { return _M_t.begin(); }
358 
359  /**
360  * Returns a read-only (constant) iterator that points to the first pair
361  * in the %map. Iteration is done in ascending order according to the
362  * keys.
363  */
364  const_iterator
365  begin() const _GLIBCXX_NOEXCEPT
366  { return _M_t.begin(); }
367 
368  /**
369  * Returns a read/write iterator that points one past the last
370  * pair in the %map. Iteration is done in ascending order
371  * according to the keys.
372  */
373  iterator
374  end() _GLIBCXX_NOEXCEPT
375  { return _M_t.end(); }
376 
377  /**
378  * Returns a read-only (constant) iterator that points one past the last
379  * pair in the %map. Iteration is done in ascending order according to
380  * the keys.
381  */
382  const_iterator
383  end() const _GLIBCXX_NOEXCEPT
384  { return _M_t.end(); }
385 
386  /**
387  * Returns a read/write reverse iterator that points to the last pair in
388  * the %map. Iteration is done in descending order according to the
389  * keys.
390  */
392  rbegin() _GLIBCXX_NOEXCEPT
393  { return _M_t.rbegin(); }
394 
395  /**
396  * Returns a read-only (constant) reverse iterator that points to the
397  * last pair in the %map. Iteration is done in descending order
398  * according to the keys.
399  */
400  const_reverse_iterator
401  rbegin() const _GLIBCXX_NOEXCEPT
402  { return _M_t.rbegin(); }
403 
404  /**
405  * Returns a read/write reverse iterator that points to one before the
406  * first pair in the %map. Iteration is done in descending order
407  * according to the keys.
408  */
410  rend() _GLIBCXX_NOEXCEPT
411  { return _M_t.rend(); }
412 
413  /**
414  * Returns a read-only (constant) reverse iterator that points to one
415  * before the first pair in the %map. Iteration is done in descending
416  * order according to the keys.
417  */
418  const_reverse_iterator
419  rend() const _GLIBCXX_NOEXCEPT
420  { return _M_t.rend(); }
421 
422 #if __cplusplus >= 201103L
423  /**
424  * Returns a read-only (constant) iterator that points to the first pair
425  * in the %map. Iteration is done in ascending order according to the
426  * keys.
427  */
428  const_iterator
429  cbegin() const noexcept
430  { return _M_t.begin(); }
431 
432  /**
433  * Returns a read-only (constant) iterator that points one past the last
434  * pair in the %map. Iteration is done in ascending order according to
435  * the keys.
436  */
437  const_iterator
438  cend() const noexcept
439  { return _M_t.end(); }
440 
441  /**
442  * Returns a read-only (constant) reverse iterator that points to the
443  * last pair in the %map. Iteration is done in descending order
444  * according to the keys.
445  */
446  const_reverse_iterator
447  crbegin() const noexcept
448  { return _M_t.rbegin(); }
449 
450  /**
451  * Returns a read-only (constant) reverse iterator that points to one
452  * before the first pair in the %map. Iteration is done in descending
453  * order according to the keys.
454  */
455  const_reverse_iterator
456  crend() const noexcept
457  { return _M_t.rend(); }
458 #endif
459 
460  // capacity
461  /** Returns true if the %map is empty. (Thus begin() would equal
462  * end().)
463  */
464  _GLIBCXX_NODISCARD bool
465  empty() const _GLIBCXX_NOEXCEPT
466  { return _M_t.empty(); }
467 
468  /** Returns the size of the %map. */
469  size_type
470  size() const _GLIBCXX_NOEXCEPT
471  { return _M_t.size(); }
472 
473  /** Returns the maximum size of the %map. */
474  size_type
475  max_size() const _GLIBCXX_NOEXCEPT
476  { return _M_t.max_size(); }
477 
478  // [23.3.1.2] element access
479  /**
480  * @brief Subscript ( @c [] ) access to %map data.
481  * @param __k The key for which data should be retrieved.
482  * @return A reference to the data of the (key,data) %pair.
483  *
484  * Allows for easy lookup with the subscript ( @c [] )
485  * operator. Returns data associated with the key specified in
486  * subscript. If the key does not exist, a pair with that key
487  * is created using default values, which is then returned.
488  *
489  * Lookup requires logarithmic time.
490  */
491  mapped_type&
492  operator[](const key_type& __k)
493  {
494  // concept requirements
495  __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
496 
497  iterator __i = lower_bound(__k);
498  // __i->first is greater than or equivalent to __k.
499  if (__i == end() || key_comp()(__k, (*__i).first))
500 #if __cplusplus >= 201103L
501  __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
503  std::tuple<>());
504 #else
505  __i = insert(__i, value_type(__k, mapped_type()));
506 #endif
507  return (*__i).second;
508  }
509 
510 #if __cplusplus >= 201103L
511  mapped_type&
512  operator[](key_type&& __k)
513  {
514  // concept requirements
515  __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
516 
517  iterator __i = lower_bound(__k);
518  // __i->first is greater than or equivalent to __k.
519  if (__i == end() || key_comp()(__k, (*__i).first))
520  __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
522  std::tuple<>());
523  return (*__i).second;
524  }
525 #endif
526 
527  // _GLIBCXX_RESOLVE_LIB_DEFECTS
528  // DR 464. Suggestion for new member functions in standard containers.
529  /**
530  * @brief Access to %map data.
531  * @param __k The key for which data should be retrieved.
532  * @return A reference to the data whose key is equivalent to @a __k, if
533  * such a data is present in the %map.
534  * @throw std::out_of_range If no such data is present.
535  */
536  mapped_type&
537  at(const key_type& __k)
538  {
539  iterator __i = lower_bound(__k);
540  if (__i == end() || key_comp()(__k, (*__i).first))
541  __throw_out_of_range(__N("map::at"));
542  return (*__i).second;
543  }
544 
545  const mapped_type&
546  at(const key_type& __k) const
547  {
548  const_iterator __i = lower_bound(__k);
549  if (__i == end() || key_comp()(__k, (*__i).first))
550  __throw_out_of_range(__N("map::at"));
551  return (*__i).second;
552  }
553 
554  // modifiers
555 #if __cplusplus >= 201103L
556  /**
557  * @brief Attempts to build and insert a std::pair into the %map.
558  *
559  * @param __args Arguments used to generate a new pair instance (see
560  * std::piecewise_contruct for passing arguments to each
561  * part of the pair constructor).
562  *
563  * @return A pair, of which the first element is an iterator that points
564  * to the possibly inserted pair, and the second is a bool that
565  * is true if the pair was actually inserted.
566  *
567  * This function attempts to build and insert a (key, value) %pair into
568  * the %map.
569  * A %map relies on unique keys and thus a %pair is only inserted if its
570  * first element (the key) is not already present in the %map.
571  *
572  * Insertion requires logarithmic time.
573  */
574  template<typename... _Args>
576  emplace(_Args&&... __args)
577  { return _M_t._M_emplace_unique(std::forward<_Args>(__args)...); }
578 
579  /**
580  * @brief Attempts to build and insert a std::pair into the %map.
581  *
582  * @param __pos An iterator that serves as a hint as to where the pair
583  * should be inserted.
584  * @param __args Arguments used to generate a new pair instance (see
585  * std::piecewise_contruct for passing arguments to each
586  * part of the pair constructor).
587  * @return An iterator that points to the element with key of the
588  * std::pair built from @a __args (may or may not be that
589  * std::pair).
590  *
591  * This function is not concerned about whether the insertion took place,
592  * and thus does not return a boolean like the single-argument emplace()
593  * does.
594  * Note that the first parameter is only a hint and can potentially
595  * improve the performance of the insertion process. A bad hint would
596  * cause no gains in efficiency.
597  *
598  * See
599  * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
600  * for more on @a hinting.
601  *
602  * Insertion requires logarithmic time (if the hint is not taken).
603  */
604  template<typename... _Args>
605  iterator
606  emplace_hint(const_iterator __pos, _Args&&... __args)
607  {
608  return _M_t._M_emplace_hint_unique(__pos,
609  std::forward<_Args>(__args)...);
610  }
611 #endif
612 
613 #if __cplusplus > 201402L
614  /// Extract a node.
615  node_type
616  extract(const_iterator __pos)
617  {
618  __glibcxx_assert(__pos != end());
619  return _M_t.extract(__pos);
620  }
621 
622  /// Extract a node.
623  node_type
624  extract(const key_type& __x)
625  { return _M_t.extract(__x); }
626 
627  /// Re-insert an extracted node.
628  insert_return_type
629  insert(node_type&& __nh)
630  { return _M_t._M_reinsert_node_unique(std::move(__nh)); }
631 
632  /// Re-insert an extracted node.
633  iterator
634  insert(const_iterator __hint, node_type&& __nh)
635  { return _M_t._M_reinsert_node_hint_unique(__hint, std::move(__nh)); }
636 
637  template<typename, typename>
638  friend class std::_Rb_tree_merge_helper;
639 
640  template<typename _Cmp2>
641  void
642  merge(map<_Key, _Tp, _Cmp2, _Alloc>& __source)
643  {
644  using _Merge_helper = _Rb_tree_merge_helper<map, _Cmp2>;
645  _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
646  }
647 
648  template<typename _Cmp2>
649  void
650  merge(map<_Key, _Tp, _Cmp2, _Alloc>&& __source)
651  { merge(__source); }
652 
653  template<typename _Cmp2>
654  void
655  merge(multimap<_Key, _Tp, _Cmp2, _Alloc>& __source)
656  {
657  using _Merge_helper = _Rb_tree_merge_helper<map, _Cmp2>;
658  _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
659  }
660 
661  template<typename _Cmp2>
662  void
663  merge(multimap<_Key, _Tp, _Cmp2, _Alloc>&& __source)
664  { merge(__source); }
665 #endif // C++17
666 
667 #if __cplusplus > 201402L
668 #define __cpp_lib_map_try_emplace 201411
669  /**
670  * @brief Attempts to build and insert a std::pair into the %map.
671  *
672  * @param __k Key to use for finding a possibly existing pair in
673  * the map.
674  * @param __args Arguments used to generate the .second for a new pair
675  * instance.
676  *
677  * @return A pair, of which the first element is an iterator that points
678  * to the possibly inserted pair, and the second is a bool that
679  * is true if the pair was actually inserted.
680  *
681  * This function attempts to build and insert a (key, value) %pair into
682  * the %map.
683  * A %map relies on unique keys and thus a %pair is only inserted if its
684  * first element (the key) is not already present in the %map.
685  * If a %pair is not inserted, this function has no effect.
686  *
687  * Insertion requires logarithmic time.
688  */
689  template <typename... _Args>
690  pair<iterator, bool>
691  try_emplace(const key_type& __k, _Args&&... __args)
692  {
693  iterator __i = lower_bound(__k);
694  if (__i == end() || key_comp()(__k, (*__i).first))
695  {
699  std::forward<_Args>(__args)...));
700  return {__i, true};
701  }
702  return {__i, false};
703  }
704 
705  // move-capable overload
706  template <typename... _Args>
707  pair<iterator, bool>
708  try_emplace(key_type&& __k, _Args&&... __args)
709  {
710  iterator __i = lower_bound(__k);
711  if (__i == end() || key_comp()(__k, (*__i).first))
712  {
716  std::forward<_Args>(__args)...));
717  return {__i, true};
718  }
719  return {__i, false};
720  }
721 
722  /**
723  * @brief Attempts to build and insert a std::pair into the %map.
724  *
725  * @param __hint An iterator that serves as a hint as to where the
726  * pair should be inserted.
727  * @param __k Key to use for finding a possibly existing pair in
728  * the map.
729  * @param __args Arguments used to generate the .second for a new pair
730  * instance.
731  * @return An iterator that points to the element with key of the
732  * std::pair built from @a __args (may or may not be that
733  * std::pair).
734  *
735  * This function is not concerned about whether the insertion took place,
736  * and thus does not return a boolean like the single-argument
737  * try_emplace() does. However, if insertion did not take place,
738  * this function has no effect.
739  * Note that the first parameter is only a hint and can potentially
740  * improve the performance of the insertion process. A bad hint would
741  * cause no gains in efficiency.
742  *
743  * See
744  * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
745  * for more on @a hinting.
746  *
747  * Insertion requires logarithmic time (if the hint is not taken).
748  */
749  template <typename... _Args>
750  iterator
751  try_emplace(const_iterator __hint, const key_type& __k,
752  _Args&&... __args)
753  {
754  iterator __i;
755  auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
756  if (__true_hint.second)
757  __i = emplace_hint(iterator(__true_hint.second),
761  std::forward<_Args>(__args)...));
762  else
763  __i = iterator(__true_hint.first);
764  return __i;
765  }
766 
767  // move-capable overload
768  template <typename... _Args>
769  iterator
770  try_emplace(const_iterator __hint, key_type&& __k, _Args&&... __args)
771  {
772  iterator __i;
773  auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
774  if (__true_hint.second)
775  __i = emplace_hint(iterator(__true_hint.second),
779  std::forward<_Args>(__args)...));
780  else
781  __i = iterator(__true_hint.first);
782  return __i;
783  }
784 #endif
785 
786  /**
787  * @brief Attempts to insert a std::pair into the %map.
788  * @param __x Pair to be inserted (see std::make_pair for easy
789  * creation of pairs).
790  *
791  * @return A pair, of which the first element is an iterator that
792  * points to the possibly inserted pair, and the second is
793  * a bool that is true if the pair was actually inserted.
794  *
795  * This function attempts to insert a (key, value) %pair into the %map.
796  * A %map relies on unique keys and thus a %pair is only inserted if its
797  * first element (the key) is not already present in the %map.
798  *
799  * Insertion requires logarithmic time.
800  * @{
801  */
803  insert(const value_type& __x)
804  { return _M_t._M_insert_unique(__x); }
805 
806 #if __cplusplus >= 201103L
807  // _GLIBCXX_RESOLVE_LIB_DEFECTS
808  // 2354. Unnecessary copying when inserting into maps with braced-init
811  { return _M_t._M_insert_unique(std::move(__x)); }
812 
813  template<typename _Pair>
814  __enable_if_t<is_constructible<value_type, _Pair>::value,
816  insert(_Pair&& __x)
817  { return _M_t._M_emplace_unique(std::forward<_Pair>(__x)); }
818 #endif
819  // @}
820 
821 #if __cplusplus >= 201103L
822  /**
823  * @brief Attempts to insert a list of std::pairs into the %map.
824  * @param __list A std::initializer_list<value_type> of pairs to be
825  * inserted.
826  *
827  * Complexity similar to that of the range constructor.
828  */
829  void
831  { insert(__list.begin(), __list.end()); }
832 #endif
833 
834  /**
835  * @brief Attempts to insert a std::pair into the %map.
836  * @param __position An iterator that serves as a hint as to where the
837  * pair should be inserted.
838  * @param __x Pair to be inserted (see std::make_pair for easy creation
839  * of pairs).
840  * @return An iterator that points to the element with key of
841  * @a __x (may or may not be the %pair passed in).
842  *
843 
844  * This function is not concerned about whether the insertion
845  * took place, and thus does not return a boolean like the
846  * single-argument insert() does. Note that the first
847  * parameter is only a hint and can potentially improve the
848  * performance of the insertion process. A bad hint would
849  * cause no gains in efficiency.
850  *
851  * See
852  * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
853  * for more on @a hinting.
854  *
855  * Insertion requires logarithmic time (if the hint is not taken).
856  * @{
857  */
858  iterator
859 #if __cplusplus >= 201103L
860  insert(const_iterator __position, const value_type& __x)
861 #else
862  insert(iterator __position, const value_type& __x)
863 #endif
864  { return _M_t._M_insert_unique_(__position, __x); }
865 
866 #if __cplusplus >= 201103L
867  // _GLIBCXX_RESOLVE_LIB_DEFECTS
868  // 2354. Unnecessary copying when inserting into maps with braced-init
869  iterator
870  insert(const_iterator __position, value_type&& __x)
871  { return _M_t._M_insert_unique_(__position, std::move(__x)); }
872 
873  template<typename _Pair>
874  __enable_if_t<is_constructible<value_type, _Pair>::value, iterator>
875  insert(const_iterator __position, _Pair&& __x)
876  {
877  return _M_t._M_emplace_hint_unique(__position,
878  std::forward<_Pair>(__x));
879  }
880 #endif
881  // @}
882 
883  /**
884  * @brief Template function that attempts to insert a range of elements.
885  * @param __first Iterator pointing to the start of the range to be
886  * inserted.
887  * @param __last Iterator pointing to the end of the range.
888  *
889  * Complexity similar to that of the range constructor.
890  */
891  template<typename _InputIterator>
892  void
893  insert(_InputIterator __first, _InputIterator __last)
894  { _M_t._M_insert_range_unique(__first, __last); }
895 
896 #if __cplusplus > 201402L
897 #define __cpp_lib_map_insertion 201411
898  /**
899  * @brief Attempts to insert or assign a std::pair into the %map.
900  * @param __k Key to use for finding a possibly existing pair in
901  * the map.
902  * @param __obj Argument used to generate the .second for a pair
903  * instance.
904  *
905  * @return A pair, of which the first element is an iterator that
906  * points to the possibly inserted pair, and the second is
907  * a bool that is true if the pair was actually inserted.
908  *
909  * This function attempts to insert a (key, value) %pair into the %map.
910  * A %map relies on unique keys and thus a %pair is only inserted if its
911  * first element (the key) is not already present in the %map.
912  * If the %pair was already in the %map, the .second of the %pair
913  * is assigned from __obj.
914  *
915  * Insertion requires logarithmic time.
916  */
917  template <typename _Obj>
919  insert_or_assign(const key_type& __k, _Obj&& __obj)
920  {
921  iterator __i = lower_bound(__k);
922  if (__i == end() || key_comp()(__k, (*__i).first))
923  {
927  std::forward<_Obj>(__obj)));
928  return {__i, true};
929  }
930  (*__i).second = std::forward<_Obj>(__obj);
931  return {__i, false};
932  }
933 
934  // move-capable overload
935  template <typename _Obj>
936  pair<iterator, bool>
937  insert_or_assign(key_type&& __k, _Obj&& __obj)
938  {
939  iterator __i = lower_bound(__k);
940  if (__i == end() || key_comp()(__k, (*__i).first))
941  {
945  std::forward<_Obj>(__obj)));
946  return {__i, true};
947  }
948  (*__i).second = std::forward<_Obj>(__obj);
949  return {__i, false};
950  }
951 
952  /**
953  * @brief Attempts to insert or assign a std::pair into the %map.
954  * @param __hint An iterator that serves as a hint as to where the
955  * pair should be inserted.
956  * @param __k Key to use for finding a possibly existing pair in
957  * the map.
958  * @param __obj Argument used to generate the .second for a pair
959  * instance.
960  *
961  * @return An iterator that points to the element with key of
962  * @a __x (may or may not be the %pair passed in).
963  *
964  * This function attempts to insert a (key, value) %pair into the %map.
965  * A %map relies on unique keys and thus a %pair is only inserted if its
966  * first element (the key) is not already present in the %map.
967  * If the %pair was already in the %map, the .second of the %pair
968  * is assigned from __obj.
969  *
970  * Insertion requires logarithmic time.
971  */
972  template <typename _Obj>
973  iterator
974  insert_or_assign(const_iterator __hint,
975  const key_type& __k, _Obj&& __obj)
976  {
977  iterator __i;
978  auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
979  if (__true_hint.second)
980  {
981  return emplace_hint(iterator(__true_hint.second),
985  std::forward<_Obj>(__obj)));
986  }
987  __i = iterator(__true_hint.first);
988  (*__i).second = std::forward<_Obj>(__obj);
989  return __i;
990  }
991 
992  // move-capable overload
993  template <typename _Obj>
994  iterator
995  insert_or_assign(const_iterator __hint, key_type&& __k, _Obj&& __obj)
996  {
997  iterator __i;
998  auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
999  if (__true_hint.second)
1000  {
1001  return emplace_hint(iterator(__true_hint.second),
1005  std::forward<_Obj>(__obj)));
1006  }
1007  __i = iterator(__true_hint.first);
1008  (*__i).second = std::forward<_Obj>(__obj);
1009  return __i;
1010  }
1011 #endif
1012 
1013 #if __cplusplus >= 201103L
1014  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1015  // DR 130. Associative erase should return an iterator.
1016  /**
1017  * @brief Erases an element from a %map.
1018  * @param __position An iterator pointing to the element to be erased.
1019  * @return An iterator pointing to the element immediately following
1020  * @a position prior to the element being erased. If no such
1021  * element exists, end() is returned.
1022  *
1023  * This function erases an element, pointed to by the given
1024  * iterator, from a %map. Note that this function only erases
1025  * the element, and that if the element is itself a pointer,
1026  * the pointed-to memory is not touched in any way. Managing
1027  * the pointer is the user's responsibility.
1028  *
1029  * @{
1030  */
1031  iterator
1032  erase(const_iterator __position)
1033  { return _M_t.erase(__position); }
1034 
1035  // LWG 2059
1036  _GLIBCXX_ABI_TAG_CXX11
1037  iterator
1038  erase(iterator __position)
1039  { return _M_t.erase(__position); }
1040  // @}
1041 #else
1042  /**
1043  * @brief Erases an element from a %map.
1044  * @param __position An iterator pointing to the element to be erased.
1045  *
1046  * This function erases an element, pointed to by the given
1047  * iterator, from a %map. Note that this function only erases
1048  * the element, and that if the element is itself a pointer,
1049  * the pointed-to memory is not touched in any way. Managing
1050  * the pointer is the user's responsibility.
1051  */
1052  void
1053  erase(iterator __position)
1054  { _M_t.erase(__position); }
1055 #endif
1056 
1057  /**
1058  * @brief Erases elements according to the provided key.
1059  * @param __x Key of element to be erased.
1060  * @return The number of elements erased.
1061  *
1062  * This function erases all the elements located by the given key from
1063  * a %map.
1064  * Note that this function only erases the element, and that if
1065  * the element is itself a pointer, the pointed-to memory is not touched
1066  * in any way. Managing the pointer is the user's responsibility.
1067  */
1068  size_type
1069  erase(const key_type& __x)
1070  { return _M_t.erase(__x); }
1071 
1072 #if __cplusplus >= 201103L
1073  // _GLIBCXX_RESOLVE_LIB_DEFECTS
1074  // DR 130. Associative erase should return an iterator.
1075  /**
1076  * @brief Erases a [first,last) range of elements from a %map.
1077  * @param __first Iterator pointing to the start of the range to be
1078  * erased.
1079  * @param __last Iterator pointing to the end of the range to
1080  * be erased.
1081  * @return The iterator @a __last.
1082  *
1083  * This function erases a sequence of elements from a %map.
1084  * Note that this function only erases the element, and that if
1085  * the element is itself a pointer, the pointed-to memory is not touched
1086  * in any way. Managing the pointer is the user's responsibility.
1087  */
1088  iterator
1089  erase(const_iterator __first, const_iterator __last)
1090  { return _M_t.erase(__first, __last); }
1091 #else
1092  /**
1093  * @brief Erases a [__first,__last) range of elements from a %map.
1094  * @param __first Iterator pointing to the start of the range to be
1095  * erased.
1096  * @param __last Iterator pointing to the end of the range to
1097  * be erased.
1098  *
1099  * This function erases a sequence of elements from a %map.
1100  * Note that this function only erases the element, and that if
1101  * the element is itself a pointer, the pointed-to memory is not touched
1102  * in any way. Managing the pointer is the user's responsibility.
1103  */
1104  void
1105  erase(iterator __first, iterator __last)
1106  { _M_t.erase(__first, __last); }
1107 #endif
1108 
1109  /**
1110  * @brief Swaps data with another %map.
1111  * @param __x A %map of the same element and allocator types.
1112  *
1113  * This exchanges the elements between two maps in constant
1114  * time. (It is only swapping a pointer, an integer, and an
1115  * instance of the @c Compare type (which itself is often
1116  * stateless and empty), so it should be quite fast.) Note
1117  * that the global std::swap() function is specialized such
1118  * that std::swap(m1,m2) will feed to this function.
1119  *
1120  * Whether the allocators are swapped depends on the allocator traits.
1121  */
1122  void
1123  swap(map& __x)
1124  _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
1125  { _M_t.swap(__x._M_t); }
1126 
1127  /**
1128  * Erases all elements in a %map. Note that this function only
1129  * erases the elements, and that if the elements themselves are
1130  * pointers, the pointed-to memory is not touched in any way.
1131  * Managing the pointer is the user's responsibility.
1132  */
1133  void
1134  clear() _GLIBCXX_NOEXCEPT
1135  { _M_t.clear(); }
1136 
1137  // observers
1138  /**
1139  * Returns the key comparison object out of which the %map was
1140  * constructed.
1141  */
1142  key_compare
1143  key_comp() const
1144  { return _M_t.key_comp(); }
1145 
1146  /**
1147  * Returns a value comparison object, built from the key comparison
1148  * object out of which the %map was constructed.
1149  */
1150  value_compare
1151  value_comp() const
1152  { return value_compare(_M_t.key_comp()); }
1153 
1154  // [23.3.1.3] map operations
1155 
1156  //@{
1157  /**
1158  * @brief Tries to locate an element in a %map.
1159  * @param __x Key of (key, value) %pair to be located.
1160  * @return Iterator pointing to sought-after element, or end() if not
1161  * found.
1162  *
1163  * This function takes a key and tries to locate the element with which
1164  * the key matches. If successful the function returns an iterator
1165  * pointing to the sought after %pair. If unsuccessful it returns the
1166  * past-the-end ( @c end() ) iterator.
1167  */
1168 
1169  iterator
1170  find(const key_type& __x)
1171  { return _M_t.find(__x); }
1172 
1173 #if __cplusplus > 201103L
1174  template<typename _Kt>
1175  auto
1176  find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
1177  { return _M_t._M_find_tr(__x); }
1178 #endif
1179  //@}
1180 
1181  //@{
1182  /**
1183  * @brief Tries to locate an element in a %map.
1184  * @param __x Key of (key, value) %pair to be located.
1185  * @return Read-only (constant) iterator pointing to sought-after
1186  * element, or end() if not found.
1187  *
1188  * This function takes a key and tries to locate the element with which
1189  * the key matches. If successful the function returns a constant
1190  * iterator pointing to the sought after %pair. If unsuccessful it
1191  * returns the past-the-end ( @c end() ) iterator.
1192  */
1193 
1194  const_iterator
1195  find(const key_type& __x) const
1196  { return _M_t.find(__x); }
1197 
1198 #if __cplusplus > 201103L
1199  template<typename _Kt>
1200  auto
1201  find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
1202  { return _M_t._M_find_tr(__x); }
1203 #endif
1204  //@}
1205 
1206  //@{
1207  /**
1208  * @brief Finds the number of elements with given key.
1209  * @param __x Key of (key, value) pairs to be located.
1210  * @return Number of elements with specified key.
1211  *
1212  * This function only makes sense for multimaps; for map the result will
1213  * either be 0 (not present) or 1 (present).
1214  */
1215  size_type
1216  count(const key_type& __x) const
1217  { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
1218 
1219 #if __cplusplus > 201103L
1220  template<typename _Kt>
1221  auto
1222  count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
1223  { return _M_t._M_count_tr(__x); }
1224 #endif
1225  //@}
1226 
1227 #if __cplusplus > 201703L
1228  //@{
1229  /**
1230  * @brief Finds whether an element with the given key exists.
1231  * @param __x Key of (key, value) pairs to be located.
1232  * @return True if there is an element with the specified key.
1233  */
1234  bool
1235  contains(const key_type& __x) const
1236  { return _M_t.find(__x) != _M_t.end(); }
1237 
1238  template<typename _Kt>
1239  auto
1240  contains(const _Kt& __x) const
1241  -> decltype(_M_t._M_find_tr(__x), void(), true)
1242  { return _M_t._M_find_tr(__x) != _M_t.end(); }
1243  //@}
1244 #endif
1245 
1246  //@{
1247  /**
1248  * @brief Finds the beginning of a subsequence matching given key.
1249  * @param __x Key of (key, value) pair to be located.
1250  * @return Iterator pointing to first element equal to or greater
1251  * than key, or end().
1252  *
1253  * This function returns the first element of a subsequence of elements
1254  * that matches the given key. If unsuccessful it returns an iterator
1255  * pointing to the first element that has a greater value than given key
1256  * or end() if no such element exists.
1257  */
1258  iterator
1259  lower_bound(const key_type& __x)
1260  { return _M_t.lower_bound(__x); }
1261 
1262 #if __cplusplus > 201103L
1263  template<typename _Kt>
1264  auto
1265  lower_bound(const _Kt& __x)
1266  -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
1267  { return iterator(_M_t._M_lower_bound_tr(__x)); }
1268 #endif
1269  //@}
1270 
1271  //@{
1272  /**
1273  * @brief Finds the beginning of a subsequence matching given key.
1274  * @param __x Key of (key, value) pair to be located.
1275  * @return Read-only (constant) iterator pointing to first element
1276  * equal to or greater than key, or end().
1277  *
1278  * This function returns the first element of a subsequence of elements
1279  * that matches the given key. If unsuccessful it returns an iterator
1280  * pointing to the first element that has a greater value than given key
1281  * or end() if no such element exists.
1282  */
1283  const_iterator
1284  lower_bound(const key_type& __x) const
1285  { return _M_t.lower_bound(__x); }
1286 
1287 #if __cplusplus > 201103L
1288  template<typename _Kt>
1289  auto
1290  lower_bound(const _Kt& __x) const
1291  -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
1292  { return const_iterator(_M_t._M_lower_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 Iterator pointing to the first element
1301  * greater than key, or end().
1302  */
1303  iterator
1304  upper_bound(const key_type& __x)
1305  { return _M_t.upper_bound(__x); }
1306 
1307 #if __cplusplus > 201103L
1308  template<typename _Kt>
1309  auto
1310  upper_bound(const _Kt& __x)
1311  -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
1312  { return iterator(_M_t._M_upper_bound_tr(__x)); }
1313 #endif
1314  //@}
1315 
1316  //@{
1317  /**
1318  * @brief Finds the end of a subsequence matching given key.
1319  * @param __x Key of (key, value) pair to be located.
1320  * @return Read-only (constant) iterator pointing to first iterator
1321  * greater than key, or end().
1322  */
1323  const_iterator
1324  upper_bound(const key_type& __x) const
1325  { return _M_t.upper_bound(__x); }
1326 
1327 #if __cplusplus > 201103L
1328  template<typename _Kt>
1329  auto
1330  upper_bound(const _Kt& __x) const
1331  -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
1332  { return const_iterator(_M_t._M_upper_bound_tr(__x)); }
1333 #endif
1334  //@}
1335 
1336  //@{
1337  /**
1338  * @brief Finds a subsequence matching given key.
1339  * @param __x Key of (key, value) pairs to be located.
1340  * @return Pair of iterators that possibly points to the subsequence
1341  * matching given key.
1342  *
1343  * This function is equivalent to
1344  * @code
1345  * std::make_pair(c.lower_bound(val),
1346  * c.upper_bound(val))
1347  * @endcode
1348  * (but is faster than making the calls separately).
1349  *
1350  * This function probably only makes sense for multimaps.
1351  */
1353  equal_range(const key_type& __x)
1354  { return _M_t.equal_range(__x); }
1355 
1356 #if __cplusplus > 201103L
1357  template<typename _Kt>
1358  auto
1359  equal_range(const _Kt& __x)
1360  -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
1361  { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
1362 #endif
1363  //@}
1364 
1365  //@{
1366  /**
1367  * @brief Finds a subsequence matching given key.
1368  * @param __x Key of (key, value) pairs to be located.
1369  * @return Pair of read-only (constant) iterators that possibly points
1370  * to the subsequence matching given key.
1371  *
1372  * This function is equivalent to
1373  * @code
1374  * std::make_pair(c.lower_bound(val),
1375  * c.upper_bound(val))
1376  * @endcode
1377  * (but is faster than making the calls separately).
1378  *
1379  * This function probably only makes sense for multimaps.
1380  */
1382  equal_range(const key_type& __x) const
1383  { return _M_t.equal_range(__x); }
1384 
1385 #if __cplusplus > 201103L
1386  template<typename _Kt>
1387  auto
1388  equal_range(const _Kt& __x) const
1390  _M_t._M_equal_range_tr(__x)))
1391  {
1393  _M_t._M_equal_range_tr(__x));
1394  }
1395 #endif
1396  //@}
1397 
1398  template<typename _K1, typename _T1, typename _C1, typename _A1>
1399  friend bool
1401  const map<_K1, _T1, _C1, _A1>&);
1402 
1403  template<typename _K1, typename _T1, typename _C1, typename _A1>
1404  friend bool
1406  const map<_K1, _T1, _C1, _A1>&);
1407  };
1408 
1409 
1410 #if __cpp_deduction_guides >= 201606
1411 
1412  template<typename _InputIterator,
1413  typename _Compare = less<__iter_key_t<_InputIterator>>,
1414  typename _Allocator = allocator<__iter_to_alloc_t<_InputIterator>>,
1415  typename = _RequireInputIter<_InputIterator>,
1416  typename = _RequireNotAllocator<_Compare>,
1417  typename = _RequireAllocator<_Allocator>>
1418  map(_InputIterator, _InputIterator,
1419  _Compare = _Compare(), _Allocator = _Allocator())
1420  -> map<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1421  _Compare, _Allocator>;
1422 
1423  template<typename _Key, typename _Tp, typename _Compare = less<_Key>,
1424  typename _Allocator = allocator<pair<const _Key, _Tp>>,
1425  typename = _RequireNotAllocator<_Compare>,
1426  typename = _RequireAllocator<_Allocator>>
1427  map(initializer_list<pair<_Key, _Tp>>,
1428  _Compare = _Compare(), _Allocator = _Allocator())
1429  -> map<_Key, _Tp, _Compare, _Allocator>;
1430 
1431  template <typename _InputIterator, typename _Allocator,
1432  typename = _RequireInputIter<_InputIterator>,
1433  typename = _RequireAllocator<_Allocator>>
1434  map(_InputIterator, _InputIterator, _Allocator)
1435  -> map<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1436  less<__iter_key_t<_InputIterator>>, _Allocator>;
1437 
1438  template<typename _Key, typename _Tp, typename _Allocator,
1439  typename = _RequireAllocator<_Allocator>>
1440  map(initializer_list<pair<_Key, _Tp>>, _Allocator)
1441  -> map<_Key, _Tp, less<_Key>, _Allocator>;
1442 
1443 #endif
1444 
1445  /**
1446  * @brief Map equality comparison.
1447  * @param __x A %map.
1448  * @param __y A %map of the same type as @a x.
1449  * @return True iff the size and elements of the maps are equal.
1450  *
1451  * This is an equivalence relation. It is linear in the size of the
1452  * maps. Maps are considered equivalent if their sizes are equal,
1453  * and if corresponding elements compare equal.
1454  */
1455  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1456  inline bool
1457  operator==(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1459  { return __x._M_t == __y._M_t; }
1460 
1461  /**
1462  * @brief Map ordering relation.
1463  * @param __x A %map.
1464  * @param __y A %map of the same type as @a x.
1465  * @return True iff @a x is lexicographically less than @a y.
1466  *
1467  * This is a total ordering relation. It is linear in the size of the
1468  * maps. The elements must be comparable with @c <.
1469  *
1470  * See std::lexicographical_compare() for how the determination is made.
1471  */
1472  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1473  inline bool
1474  operator<(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1476  { return __x._M_t < __y._M_t; }
1477 
1478  /// Based on operator==
1479  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1480  inline bool
1481  operator!=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1483  { return !(__x == __y); }
1484 
1485  /// Based on operator<
1486  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1487  inline bool
1488  operator>(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1490  { return __y < __x; }
1491 
1492  /// Based on operator<
1493  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1494  inline bool
1495  operator<=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1497  { return !(__y < __x); }
1498 
1499  /// Based on operator<
1500  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1501  inline bool
1502  operator>=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1504  { return !(__x < __y); }
1505 
1506  /// See std::map::swap().
1507  template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1508  inline void
1511  _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
1512  { __x.swap(__y); }
1513 
1514 _GLIBCXX_END_NAMESPACE_CONTAINER
1515 
1516 #if __cplusplus > 201402L
1517  // Allow std::map access to internals of compatible maps.
1518  template<typename _Key, typename _Val, typename _Cmp1, typename _Alloc,
1519  typename _Cmp2>
1520  struct
1521  _Rb_tree_merge_helper<_GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>,
1522  _Cmp2>
1523  {
1524  private:
1525  friend class _GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>;
1526 
1527  static auto&
1528  _S_get_tree(_GLIBCXX_STD_C::map<_Key, _Val, _Cmp2, _Alloc>& __map)
1529  { return __map._M_t; }
1530 
1531  static auto&
1532  _S_get_tree(_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp2, _Alloc>& __map)
1533  { return __map._M_t; }
1534  };
1535 #endif // C++17
1536 
1537 _GLIBCXX_END_NAMESPACE_VERSION
1538 } // namespace std
1539 
1540 #endif /* _STL_MAP_H */
std::map::map
map()=default
Default constructor creates no elements.
std::is_nothrow_copy_constructible
is_nothrow_copy_constructible
Definition: type_traits:1027
std::map::begin
const_iterator begin() const noexcept
Definition: stl_map.h:365
std::map::at
mapped_type & at(const key_type &__k)
Access to map data.
Definition: stl_map.h:537
std::map::map
map(_InputIterator __first, _InputIterator __last, const _Compare &__comp, const allocator_type &__a=allocator_type())
Builds a map from a range.
Definition: stl_map.h:290
std::map::cend
const_iterator cend() const noexcept
Definition: stl_map.h:438
std::map::lower_bound
const_iterator lower_bound(const key_type &__x) const
Finds the beginning of a subsequence matching given key.
Definition: stl_map.h:1284
std::map::map
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:228
std::map::size
size_type size() const noexcept
Definition: stl_map.h:470
std::map::lower_bound
auto lower_bound(const _Kt &__x) -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1265
std::map::count
auto count(const _Kt &__x) const -> decltype(_M_t._M_count_tr(__x))
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1222
std::map::insert
__enable_if_t< is_constructible< value_type, _Pair >::value, pair< iterator, bool > > insert(_Pair &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:816
std::map::upper_bound
const_iterator upper_bound(const key_type &__x) const
Finds the end of a subsequence matching given key.
Definition: stl_map.h:1324
std::map::erase
iterator erase(const_iterator __first, const_iterator __last)
Erases a [first,last) range of elements from a map.
Definition: stl_map.h:1089
std::map::insert
iterator insert(const_iterator __position, value_type &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:870
std::map::cbegin
const_iterator cbegin() const noexcept
Definition: stl_map.h:429
std::pair::first
_T1 first
The first member.
Definition: stl_pair.h:216
std::map::insert
void insert(_InputIterator __first, _InputIterator __last)
Template function that attempts to insert a range of elements.
Definition: stl_map.h:893
std::map::insert
void insert(std::initializer_list< value_type > __list)
Attempts to insert a list of std::pairs into the map.
Definition: stl_map.h:830
std::map::equal_range
std::pair< const_iterator, const_iterator > equal_range(const key_type &__x) const
Finds a subsequence matching given key.
Definition: stl_map.h:1382
std::map::find
iterator find(const key_type &__x)
Tries to locate an element in a map.
Definition: stl_map.h:1170
std::tuple
Primary class template, tuple.
Definition: tuple:56
functexcept.h
std::iterator
Common iterator class.
Definition: stl_iterator_base_types.h:127
std::map::~map
~map()=default
std
ISO C++ entities toplevel namespace is std.
std::map::lower_bound
auto lower_bound(const _Kt &__x) const -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1290
std::map::emplace
std::pair< iterator, bool > emplace(_Args &&... __args)
Attempts to build and insert a std::pair into the map.
Definition: stl_map.h:576
std::map::find
auto find(const _Kt &__x) const -> decltype(_M_t._M_find_tr(__x))
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1201
std::map::insert
iterator insert(const_iterator __position, const value_type &__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:860
std::map::equal_range
std::pair< iterator, iterator > equal_range(const key_type &__x)
Finds a subsequence matching given key.
Definition: stl_map.h:1353
std::map::operator[]
mapped_type & operator[](const key_type &__k)
Subscript ( [] ) access to map data.
Definition: stl_map.h:492
__gnu_cxx::__alloc_traits
Uniform interface to C++98 and C++11 allocators.
Definition: ext/alloc_traits.h:48
std::map::swap
void swap(map &__x) noexcept(/*conditional */)
Swaps data with another map.
Definition: stl_map.h:1123
std::map::value_comp
value_compare value_comp() const
Definition: stl_map.h:1151
std::map::get_allocator
allocator_type get_allocator() const noexcept
Get a copy of the memory allocation object.
Definition: stl_map.h:346
std::map::operator<
friend bool operator<(const map< _K1, _T1, _C1, _A1 > &, const map< _K1, _T1, _C1, _A1 > &)
Attempts to insert a std::pair into the map.
std::map::operator=
map & operator=(initializer_list< value_type > __l)
Map list assignment operator.
Definition: stl_map.h:337
std::map::map
map(const _Compare &__comp, const allocator_type &__a=allocator_type())
Creates a map with no elements.
Definition: stl_map.h:194
std::map::crend
const_reverse_iterator crend() const noexcept
Definition: stl_map.h:456
std::map::end
iterator end() noexcept
Definition: stl_map.h:374
initializer_list
std::map::map
map(const map &__m, const allocator_type &__a)
Allocator-extended copy constructor.
Definition: stl_map.h:240
std::map::equal_range
auto equal_range(const _Kt &__x) -> decltype(pair< iterator, iterator >(_M_t._M_equal_range_tr(__x)))
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1359
std::map::erase
_GLIBCXX_ABI_TAG_CXX11 iterator erase(iterator __position)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1038
std::map::empty
bool empty() const noexcept
Definition: stl_map.h:465
std::map::rend
reverse_iterator rend() noexcept
Definition: stl_map.h:410
std::map::count
size_type count(const key_type &__x) const
Finds the number of elements with given key.
Definition: stl_map.h:1216
std::map::erase
size_type erase(const key_type &__x)
Erases elements according to the provided key.
Definition: stl_map.h:1069
std::map::map
map(const allocator_type &__a)
Allocator-extended default constructor.
Definition: stl_map.h:236
std::map::erase
iterator erase(const_iterator __position)
Erases an element from a map.
Definition: stl_map.h:1032
std::map
A standard container made up of (key,value) pairs, which can be retrieved based on a key,...
Definition: stl_map.h:100
std::map::find
auto find(const _Kt &__x) -> decltype(_M_t._M_find_tr(__x))
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1176
std::map::insert
std::pair< iterator, bool > insert(value_type &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:810
std::map::map
map(_InputIterator __first, _InputIterator __last, const allocator_type &__a)
Allocator-extended range constructor.
Definition: stl_map.h:256
std::map::map
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:244
std::map::crbegin
const_reverse_iterator crbegin() const noexcept
Definition: stl_map.h:447
std::map::rbegin
reverse_iterator rbegin() noexcept
Definition: stl_map.h:392
std::map::operator==
friend bool operator==(const map< _K1, _T1, _C1, _A1 > &, const map< _K1, _T1, _C1, _A1 > &)
Attempts to insert a std::pair into the map.
std::map::equal_range
auto equal_range(const _Kt &__x) const -> decltype(pair< const_iterator, const_iterator >(_M_t._M_equal_range_tr(__x)))
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1388
std::map::rend
const_reverse_iterator rend() const noexcept
Definition: stl_map.h:419
std::map::lower_bound
iterator lower_bound(const key_type &__x)
Finds the beginning of a subsequence matching given key.
Definition: stl_map.h:1259
std::multimap
A standard container made up of (key,value) pairs, which can be retrieved based on a key,...
Definition: stl_map.h:72
std::map::upper_bound
auto upper_bound(const _Kt &__x) const -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1330
std::map::map
map(_InputIterator __first, _InputIterator __last)
Builds a map from a range.
Definition: stl_map.h:273
std::map::max_size
size_type max_size() const noexcept
Definition: stl_map.h:475
std::map::upper_bound
auto upper_bound(const _Kt &__x) -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
Attempts to insert a std::pair into the map.
Definition: stl_map.h:1310
std::map::find
const_iterator find(const key_type &__x) const
Tries to locate an element in a map.
Definition: stl_map.h:1195
std::map::clear
void clear() noexcept
Definition: stl_map.h:1134
std::is_same
is_same
Definition: type_traits:582
std::map::emplace_hint
iterator emplace_hint(const_iterator __pos, _Args &&... __args)
Attempts to build and insert a std::pair into the map.
Definition: stl_map.h:606
std::map::begin
iterator begin() noexcept
Definition: stl_map.h:356
std::reverse_iterator
Definition: bits/stl_iterator.h:110
tuple
std::forward_as_tuple
constexpr tuple< _Elements &&... > forward_as_tuple(_Elements &&... __args) noexcept
std::forward_as_tuple
Definition: tuple:1485
std::map::map
map(initializer_list< value_type > __l, const allocator_type &__a)
Allocator-extended initialier-list constructor.
Definition: stl_map.h:250
std::map::insert
std::pair< iterator, bool > insert(const value_type &__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:803
std::map::key_comp
key_compare key_comp() const
Definition: stl_map.h:1143
std::initializer_list
initializer_list
Definition: initializer_list:47
std::map::end
const_iterator end() const noexcept
Definition: stl_map.h:383
std::map::insert
__enable_if_t< is_constructible< value_type, _Pair >::value, iterator > insert(const_iterator __position, _Pair &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:875
std::map::rbegin
const_reverse_iterator rbegin() const noexcept
Definition: stl_map.h:401
std::binary_function
Definition: stl_function.h:118
std::pair
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:210
std::piecewise_construct
constexpr piecewise_construct_t piecewise_construct
Tag for piecewise construction of std::pair objects.
Definition: stl_pair.h:82
concept_check.h
std::map::upper_bound
iterator upper_bound(const key_type &__x)
Finds the end of a subsequence matching given key.
Definition: stl_map.h:1304
std::move
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Definition: move.h:101
std::map::operator=
map & operator=(const map &)=default
Map assignment operator.