libstdc++
stl_map.h
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1// Map implementation -*- C++ -*-
2
3// Copyright (C) 2001-2022 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
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9// any later version.
10
11// This library is distributed in the hope that it will be useful,
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13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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15
16// Under Section 7 of GPL version 3, you are granted additional
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18// 3.1, as published by the Free Software Foundation.
19
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22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996,1997
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
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
66namespace 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#pragma GCC diagnostic push
130#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
131 class value_compare
132 : public std::binary_function<value_type, value_type, bool>
133 {
134 friend class map<_Key, _Tp, _Compare, _Alloc>;
135 protected:
136 _Compare comp;
137
138 value_compare(_Compare __c)
139 : comp(__c) { }
140
141 public:
142 bool operator()(const value_type& __x, const value_type& __y) const
143 { return comp(__x.first, __y.first); }
144 };
145#pragma GCC diagnostic pop
146
147 private:
148 /// This turns a red-black tree into a [multi]map.
150 rebind<value_type>::other _Pair_alloc_type;
151
152 typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
153 key_compare, _Pair_alloc_type> _Rep_type;
154
155 /// The actual tree structure.
156 _Rep_type _M_t;
157
159
160#if __cplusplus >= 201703L
161 template<typename _Up, typename _Vp = remove_reference_t<_Up>>
162 static constexpr bool __usable_key
163 = __or_v<is_same<const _Vp, const _Key>,
164 __and_<is_scalar<_Vp>, is_scalar<_Key>>>;
165#endif
166
167 public:
168 // many of these are specified differently in ISO, but the following are
169 // "functionally equivalent"
170 typedef typename _Alloc_traits::pointer pointer;
171 typedef typename _Alloc_traits::const_pointer const_pointer;
172 typedef typename _Alloc_traits::reference reference;
173 typedef typename _Alloc_traits::const_reference const_reference;
174 typedef typename _Rep_type::iterator iterator;
175 typedef typename _Rep_type::const_iterator const_iterator;
176 typedef typename _Rep_type::size_type size_type;
177 typedef typename _Rep_type::difference_type difference_type;
180
181#if __cplusplus > 201402L
182 using node_type = typename _Rep_type::node_type;
183 using insert_return_type = typename _Rep_type::insert_return_type;
184#endif
185
186 // [23.3.1.1] construct/copy/destroy
187 // (get_allocator() is also listed in this section)
188
189 /**
190 * @brief Default constructor creates no elements.
191 */
192#if __cplusplus < 201103L
193 map() : _M_t() { }
194#else
195 map() = default;
196#endif
197
198 /**
199 * @brief Creates a %map with no elements.
200 * @param __comp A comparison object.
201 * @param __a An allocator object.
202 */
203 explicit
204 map(const _Compare& __comp,
205 const allocator_type& __a = allocator_type())
206 : _M_t(__comp, _Pair_alloc_type(__a)) { }
207
208 /**
209 * @brief %Map copy constructor.
210 *
211 * Whether the allocator is copied depends on the allocator traits.
212 */
213#if __cplusplus < 201103L
214 map(const map& __x)
215 : _M_t(__x._M_t) { }
216#else
217 map(const map&) = default;
218
219 /**
220 * @brief %Map move constructor.
221 *
222 * The newly-created %map contains the exact contents of the moved
223 * instance. The moved instance is a valid, but unspecified, %map.
224 */
225 map(map&&) = default;
226
227 /**
228 * @brief Builds a %map from an initializer_list.
229 * @param __l An initializer_list.
230 * @param __comp A comparison object.
231 * @param __a An allocator object.
232 *
233 * Create a %map consisting of copies of the elements in the
234 * initializer_list @a __l.
235 * This is linear in N if the range is already sorted, and NlogN
236 * otherwise (where N is @a __l.size()).
237 */
239 const _Compare& __comp = _Compare(),
240 const allocator_type& __a = allocator_type())
241 : _M_t(__comp, _Pair_alloc_type(__a))
242 { _M_t._M_insert_range_unique(__l.begin(), __l.end()); }
243
244 /// Allocator-extended default constructor.
245 explicit
246 map(const allocator_type& __a)
247 : _M_t(_Pair_alloc_type(__a)) { }
248
249 /// Allocator-extended copy constructor.
250 map(const map& __m, const __type_identity_t<allocator_type>& __a)
251 : _M_t(__m._M_t, _Pair_alloc_type(__a)) { }
252
253 /// Allocator-extended move constructor.
254 map(map&& __m, const __type_identity_t<allocator_type>& __a)
256 && _Alloc_traits::_S_always_equal())
257 : _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { }
258
259 /// Allocator-extended initialier-list constructor.
260 map(initializer_list<value_type> __l, const allocator_type& __a)
261 : _M_t(_Pair_alloc_type(__a))
262 { _M_t._M_insert_range_unique(__l.begin(), __l.end()); }
263
264 /// Allocator-extended range constructor.
265 template<typename _InputIterator>
266 map(_InputIterator __first, _InputIterator __last,
267 const allocator_type& __a)
268 : _M_t(_Pair_alloc_type(__a))
269 { _M_t._M_insert_range_unique(__first, __last); }
270#endif
271
272 /**
273 * @brief Builds a %map from a range.
274 * @param __first An input iterator.
275 * @param __last An input iterator.
276 *
277 * Create a %map consisting of copies of the elements from
278 * [__first,__last). This is linear in N if the range is
279 * already sorted, and NlogN otherwise (where N is
280 * distance(__first,__last)).
281 */
282 template<typename _InputIterator>
283 map(_InputIterator __first, _InputIterator __last)
284 : _M_t()
285 { _M_t._M_insert_range_unique(__first, __last); }
286
287 /**
288 * @brief Builds a %map from a range.
289 * @param __first An input iterator.
290 * @param __last An input iterator.
291 * @param __comp A comparison functor.
292 * @param __a An allocator object.
293 *
294 * Create a %map consisting of copies of the elements from
295 * [__first,__last). This is linear in N if the range is
296 * already sorted, and NlogN otherwise (where N is
297 * distance(__first,__last)).
298 */
299 template<typename _InputIterator>
300 map(_InputIterator __first, _InputIterator __last,
301 const _Compare& __comp,
302 const allocator_type& __a = allocator_type())
303 : _M_t(__comp, _Pair_alloc_type(__a))
304 { _M_t._M_insert_range_unique(__first, __last); }
305
306#if __cplusplus >= 201103L
307 /**
308 * The dtor only erases the elements, and note that if the elements
309 * themselves are pointers, the pointed-to memory is not touched in any
310 * way. Managing the pointer is the user's responsibility.
311 */
312 ~map() = default;
313#endif
314
315 /**
316 * @brief %Map assignment operator.
317 *
318 * Whether the allocator is copied depends on the allocator traits.
319 */
320#if __cplusplus < 201103L
321 map&
322 operator=(const map& __x)
323 {
324 _M_t = __x._M_t;
325 return *this;
326 }
327#else
328 map&
329 operator=(const map&) = default;
330
331 /// Move assignment operator.
332 map&
333 operator=(map&&) = default;
334
335 /**
336 * @brief %Map list assignment operator.
337 * @param __l An initializer_list.
338 *
339 * This function fills a %map with copies of the elements in the
340 * initializer list @a __l.
341 *
342 * Note that the assignment completely changes the %map and
343 * that the resulting %map's size is the same as the number
344 * of elements assigned.
345 */
346 map&
348 {
349 _M_t._M_assign_unique(__l.begin(), __l.end());
350 return *this;
351 }
352#endif
353
354 /// Get a copy of the memory allocation object.
355 allocator_type
356 get_allocator() const _GLIBCXX_NOEXCEPT
357 { return allocator_type(_M_t.get_allocator()); }
358
359 // iterators
360 /**
361 * Returns a read/write iterator that points to the first pair in the
362 * %map.
363 * Iteration is done in ascending order according to the keys.
364 */
366 begin() _GLIBCXX_NOEXCEPT
367 { return _M_t.begin(); }
368
369 /**
370 * Returns a read-only (constant) iterator that points to the first pair
371 * in the %map. Iteration is done in ascending order according to the
372 * keys.
373 */
374 const_iterator
375 begin() const _GLIBCXX_NOEXCEPT
376 { return _M_t.begin(); }
377
378 /**
379 * Returns a read/write iterator that points one past the last
380 * pair in the %map. Iteration is done in ascending order
381 * according to the keys.
382 */
384 end() _GLIBCXX_NOEXCEPT
385 { return _M_t.end(); }
386
387 /**
388 * Returns a read-only (constant) iterator that points one past the last
389 * pair in the %map. Iteration is done in ascending order according to
390 * the keys.
391 */
392 const_iterator
393 end() const _GLIBCXX_NOEXCEPT
394 { return _M_t.end(); }
395
396 /**
397 * Returns a read/write reverse iterator that points to the last pair in
398 * the %map. Iteration is done in descending order according to the
399 * keys.
400 */
402 rbegin() _GLIBCXX_NOEXCEPT
403 { return _M_t.rbegin(); }
404
405 /**
406 * Returns a read-only (constant) reverse iterator that points to the
407 * last pair in the %map. Iteration is done in descending order
408 * according to the keys.
409 */
410 const_reverse_iterator
411 rbegin() const _GLIBCXX_NOEXCEPT
412 { return _M_t.rbegin(); }
413
414 /**
415 * Returns a read/write reverse iterator that points to one before the
416 * first pair in the %map. Iteration is done in descending order
417 * according to the keys.
418 */
420 rend() _GLIBCXX_NOEXCEPT
421 { return _M_t.rend(); }
422
423 /**
424 * Returns a read-only (constant) reverse iterator that points to one
425 * before the first pair in the %map. Iteration is done in descending
426 * order according to the keys.
427 */
428 const_reverse_iterator
429 rend() const _GLIBCXX_NOEXCEPT
430 { return _M_t.rend(); }
431
432#if __cplusplus >= 201103L
433 /**
434 * Returns a read-only (constant) iterator that points to the first pair
435 * in the %map. Iteration is done in ascending order according to the
436 * keys.
437 */
438 const_iterator
439 cbegin() const noexcept
440 { return _M_t.begin(); }
441
442 /**
443 * Returns a read-only (constant) iterator that points one past the last
444 * pair in the %map. Iteration is done in ascending order according to
445 * the keys.
446 */
447 const_iterator
448 cend() const noexcept
449 { return _M_t.end(); }
450
451 /**
452 * Returns a read-only (constant) reverse iterator that points to the
453 * last pair in the %map. Iteration is done in descending order
454 * according to the keys.
455 */
456 const_reverse_iterator
457 crbegin() const noexcept
458 { return _M_t.rbegin(); }
459
460 /**
461 * Returns a read-only (constant) reverse iterator that points to one
462 * before the first pair in the %map. Iteration is done in descending
463 * order according to the keys.
464 */
465 const_reverse_iterator
466 crend() const noexcept
467 { return _M_t.rend(); }
468#endif
469
470 // capacity
471 /** Returns true if the %map is empty. (Thus begin() would equal
472 * end().)
473 */
474 _GLIBCXX_NODISCARD bool
475 empty() const _GLIBCXX_NOEXCEPT
476 { return _M_t.empty(); }
477
478 /** Returns the size of the %map. */
479 size_type
480 size() const _GLIBCXX_NOEXCEPT
481 { return _M_t.size(); }
482
483 /** Returns the maximum size of the %map. */
484 size_type
485 max_size() const _GLIBCXX_NOEXCEPT
486 { return _M_t.max_size(); }
487
488 // [23.3.1.2] element access
489 /**
490 * @brief Subscript ( @c [] ) access to %map data.
491 * @param __k The key for which data should be retrieved.
492 * @return A reference to the data of the (key,data) %pair.
493 *
494 * Allows for easy lookup with the subscript ( @c [] )
495 * operator. Returns data associated with the key specified in
496 * subscript. If the key does not exist, a pair with that key
497 * is created using default values, which is then returned.
498 *
499 * Lookup requires logarithmic time.
500 */
501 mapped_type&
502 operator[](const key_type& __k)
503 {
504 // concept requirements
505 __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
506
507 iterator __i = lower_bound(__k);
508 // __i->first is greater than or equivalent to __k.
509 if (__i == end() || key_comp()(__k, (*__i).first))
510#if __cplusplus >= 201103L
511 __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
513 std::tuple<>());
514#else
515 __i = insert(__i, value_type(__k, mapped_type()));
516#endif
517 return (*__i).second;
518 }
519
520#if __cplusplus >= 201103L
521 mapped_type&
522 operator[](key_type&& __k)
523 {
524 // concept requirements
525 __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
526
527 iterator __i = lower_bound(__k);
528 // __i->first is greater than or equivalent to __k.
529 if (__i == end() || key_comp()(__k, (*__i).first))
530 __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
532 std::tuple<>());
533 return (*__i).second;
534 }
535#endif
536
537 // _GLIBCXX_RESOLVE_LIB_DEFECTS
538 // DR 464. Suggestion for new member functions in standard containers.
539 /**
540 * @brief Access to %map data.
541 * @param __k The key for which data should be retrieved.
542 * @return A reference to the data whose key is equivalent to @a __k, if
543 * such a data is present in the %map.
544 * @throw std::out_of_range If no such data is present.
545 */
546 mapped_type&
547 at(const key_type& __k)
548 {
549 iterator __i = lower_bound(__k);
550 if (__i == end() || key_comp()(__k, (*__i).first))
551 __throw_out_of_range(__N("map::at"));
552 return (*__i).second;
553 }
554
555 const mapped_type&
556 at(const key_type& __k) const
557 {
558 const_iterator __i = lower_bound(__k);
559 if (__i == end() || key_comp()(__k, (*__i).first))
560 __throw_out_of_range(__N("map::at"));
561 return (*__i).second;
562 }
563
564 // modifiers
565#if __cplusplus >= 201103L
566 /**
567 * @brief Attempts to build and insert a std::pair into the %map.
568 *
569 * @param __args Arguments used to generate a new pair instance (see
570 * std::piecewise_contruct for passing arguments to each
571 * part of the pair constructor).
572 *
573 * @return A pair, of which the first element is an iterator that points
574 * to the possibly inserted pair, and the second is a bool that
575 * is true if the pair was actually inserted.
576 *
577 * This function attempts to build and insert a (key, value) %pair into
578 * the %map.
579 * A %map relies on unique keys and thus a %pair is only inserted if its
580 * first element (the key) is not already present in the %map.
581 *
582 * Insertion requires logarithmic time.
583 */
584 template<typename... _Args>
586 emplace(_Args&&... __args)
587 {
588#if __cplusplus >= 201703L
589 if constexpr (sizeof...(_Args) == 2)
590 if constexpr (is_same_v<allocator_type, allocator<value_type>>)
591 {
592 auto&& [__a, __v] = pair<_Args&...>(__args...);
593 if constexpr (__usable_key<decltype(__a)>)
594 {
595 const key_type& __k = __a;
596 iterator __i = lower_bound(__k);
597 if (__i == end() || key_comp()(__k, (*__i).first))
598 {
599 __i = emplace_hint(__i, std::forward<_Args>(__args)...);
600 return {__i, true};
601 }
602 return {__i, false};
603 }
604 }
605#endif
606 return _M_t._M_emplace_unique(std::forward<_Args>(__args)...);
607 }
608
609 /**
610 * @brief Attempts to build and insert a std::pair into the %map.
611 *
612 * @param __pos An iterator that serves as a hint as to where the pair
613 * should be inserted.
614 * @param __args Arguments used to generate a new pair instance (see
615 * std::piecewise_contruct for passing arguments to each
616 * part of the pair constructor).
617 * @return An iterator that points to the element with key of the
618 * std::pair built from @a __args (may or may not be that
619 * std::pair).
620 *
621 * This function is not concerned about whether the insertion took place,
622 * and thus does not return a boolean like the single-argument emplace()
623 * does.
624 * Note that the first parameter is only a hint and can potentially
625 * improve the performance of the insertion process. A bad hint would
626 * cause no gains in efficiency.
627 *
628 * See
629 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
630 * for more on @a hinting.
631 *
632 * Insertion requires logarithmic time (if the hint is not taken).
633 */
634 template<typename... _Args>
636 emplace_hint(const_iterator __pos, _Args&&... __args)
637 {
638 return _M_t._M_emplace_hint_unique(__pos,
639 std::forward<_Args>(__args)...);
640 }
641#endif
642
643#if __cplusplus > 201402L
644 /// Extract a node.
645 node_type
646 extract(const_iterator __pos)
647 {
648 __glibcxx_assert(__pos != end());
649 return _M_t.extract(__pos);
650 }
651
652 /// Extract a node.
653 node_type
654 extract(const key_type& __x)
655 { return _M_t.extract(__x); }
656
657 /// Re-insert an extracted node.
658 insert_return_type
659 insert(node_type&& __nh)
660 { return _M_t._M_reinsert_node_unique(std::move(__nh)); }
661
662 /// Re-insert an extracted node.
664 insert(const_iterator __hint, node_type&& __nh)
665 { return _M_t._M_reinsert_node_hint_unique(__hint, std::move(__nh)); }
666
667 template<typename, typename>
668 friend struct std::_Rb_tree_merge_helper;
669
670 template<typename _Cmp2>
671 void
672 merge(map<_Key, _Tp, _Cmp2, _Alloc>& __source)
673 {
674 using _Merge_helper = _Rb_tree_merge_helper<map, _Cmp2>;
675 _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
676 }
677
678 template<typename _Cmp2>
679 void
680 merge(map<_Key, _Tp, _Cmp2, _Alloc>&& __source)
681 { merge(__source); }
682
683 template<typename _Cmp2>
684 void
685 merge(multimap<_Key, _Tp, _Cmp2, _Alloc>& __source)
686 {
687 using _Merge_helper = _Rb_tree_merge_helper<map, _Cmp2>;
688 _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
689 }
690
691 template<typename _Cmp2>
692 void
693 merge(multimap<_Key, _Tp, _Cmp2, _Alloc>&& __source)
694 { merge(__source); }
695#endif // C++17
696
697#if __cplusplus > 201402L
698#define __cpp_lib_map_try_emplace 201411L
699 /**
700 * @brief Attempts to build and insert a std::pair into the %map.
701 *
702 * @param __k Key to use for finding a possibly existing pair in
703 * the map.
704 * @param __args Arguments used to generate the .second for a new pair
705 * instance.
706 *
707 * @return A pair, of which the first element is an iterator that points
708 * to the possibly inserted pair, and the second is a bool that
709 * is true if the pair was actually inserted.
710 *
711 * This function attempts to build and insert a (key, value) %pair into
712 * the %map.
713 * A %map relies on unique keys and thus a %pair is only inserted if its
714 * first element (the key) is not already present in the %map.
715 * If a %pair is not inserted, this function has no effect.
716 *
717 * Insertion requires logarithmic time.
718 */
719 template <typename... _Args>
720 pair<iterator, bool>
721 try_emplace(const key_type& __k, _Args&&... __args)
722 {
723 iterator __i = lower_bound(__k);
724 if (__i == end() || key_comp()(__k, (*__i).first))
725 {
729 std::forward<_Args>(__args)...));
730 return {__i, true};
731 }
732 return {__i, false};
733 }
734
735 // move-capable overload
736 template <typename... _Args>
738 try_emplace(key_type&& __k, _Args&&... __args)
739 {
740 iterator __i = lower_bound(__k);
741 if (__i == end() || key_comp()(__k, (*__i).first))
742 {
746 std::forward<_Args>(__args)...));
747 return {__i, true};
748 }
749 return {__i, false};
750 }
751
752 /**
753 * @brief Attempts to build and insert a std::pair into the %map.
754 *
755 * @param __hint An iterator that serves as a hint as to where the
756 * pair should be inserted.
757 * @param __k Key to use for finding a possibly existing pair in
758 * the map.
759 * @param __args Arguments used to generate the .second for a new pair
760 * instance.
761 * @return An iterator that points to the element with key of the
762 * std::pair built from @a __args (may or may not be that
763 * std::pair).
764 *
765 * This function is not concerned about whether the insertion took place,
766 * and thus does not return a boolean like the single-argument
767 * try_emplace() does. However, if insertion did not take place,
768 * this function has no effect.
769 * Note that the first parameter is only a hint and can potentially
770 * improve the performance of the insertion process. A bad hint would
771 * cause no gains in efficiency.
772 *
773 * See
774 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
775 * for more on @a hinting.
776 *
777 * Insertion requires logarithmic time (if the hint is not taken).
778 */
779 template <typename... _Args>
780 iterator
781 try_emplace(const_iterator __hint, const key_type& __k,
782 _Args&&... __args)
783 {
784 iterator __i;
785 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
786 if (__true_hint.second)
787 __i = emplace_hint(iterator(__true_hint.second),
791 std::forward<_Args>(__args)...));
792 else
793 __i = iterator(__true_hint.first);
794 return __i;
795 }
796
797 // move-capable overload
798 template <typename... _Args>
800 try_emplace(const_iterator __hint, key_type&& __k, _Args&&... __args)
801 {
802 iterator __i;
803 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
804 if (__true_hint.second)
805 __i = emplace_hint(iterator(__true_hint.second),
809 std::forward<_Args>(__args)...));
810 else
811 __i = iterator(__true_hint.first);
812 return __i;
813 }
814#endif
815
816 /**
817 * @brief Attempts to insert a std::pair into the %map.
818 * @param __x Pair to be inserted (see std::make_pair for easy
819 * creation of pairs).
820 *
821 * @return A pair, of which the first element is an iterator that
822 * points to the possibly inserted pair, and the second is
823 * a bool that is true if the pair was actually inserted.
824 *
825 * This function attempts to insert a (key, value) %pair into the %map.
826 * A %map relies on unique keys and thus a %pair is only inserted if its
827 * first element (the key) is not already present in the %map.
828 *
829 * Insertion requires logarithmic time.
830 * @{
831 */
833 insert(const value_type& __x)
834 { return _M_t._M_insert_unique(__x); }
835
836#if __cplusplus >= 201103L
837 // _GLIBCXX_RESOLVE_LIB_DEFECTS
838 // 2354. Unnecessary copying when inserting into maps with braced-init
841 { return _M_t._M_insert_unique(std::move(__x)); }
842
843 template<typename _Pair>
844 __enable_if_t<is_constructible<value_type, _Pair>::value,
846 insert(_Pair&& __x)
847 {
848#if __cplusplus >= 201703L
849 using _P2 = remove_reference_t<_Pair>;
850 if constexpr (__is_pair<_P2>)
851 if constexpr (is_same_v<allocator_type, allocator<value_type>>)
852 if constexpr (__usable_key<typename _P2::first_type>)
853 {
854 const key_type& __k = __x.first;
855 iterator __i = lower_bound(__k);
856 if (__i == end() || key_comp()(__k, (*__i).first))
857 {
858 __i = emplace_hint(__i, std::forward<_Pair>(__x));
859 return {__i, true};
860 }
861 return {__i, false};
862 }
863#endif
864 return _M_t._M_emplace_unique(std::forward<_Pair>(__x));
865 }
866#endif
867 /// @}
868
869#if __cplusplus >= 201103L
870 /**
871 * @brief Attempts to insert a list of std::pairs into the %map.
872 * @param __list A std::initializer_list<value_type> of pairs to be
873 * inserted.
874 *
875 * Complexity similar to that of the range constructor.
876 */
877 void
879 { insert(__list.begin(), __list.end()); }
880#endif
881
882 /**
883 * @brief Attempts to insert a std::pair into the %map.
884 * @param __position An iterator that serves as a hint as to where the
885 * pair should be inserted.
886 * @param __x Pair to be inserted (see std::make_pair for easy creation
887 * of pairs).
888 * @return An iterator that points to the element with key of
889 * @a __x (may or may not be the %pair passed in).
890 *
891
892 * This function is not concerned about whether the insertion
893 * took place, and thus does not return a boolean like the
894 * single-argument insert() does. Note that the first
895 * parameter is only a hint and can potentially improve the
896 * performance of the insertion process. A bad hint would
897 * cause no gains in efficiency.
898 *
899 * See
900 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
901 * for more on @a hinting.
902 *
903 * Insertion requires logarithmic time (if the hint is not taken).
904 * @{
905 */
907#if __cplusplus >= 201103L
908 insert(const_iterator __position, const value_type& __x)
909#else
910 insert(iterator __position, const value_type& __x)
911#endif
912 { return _M_t._M_insert_unique_(__position, __x); }
913
914#if __cplusplus >= 201103L
915 // _GLIBCXX_RESOLVE_LIB_DEFECTS
916 // 2354. Unnecessary copying when inserting into maps with braced-init
918 insert(const_iterator __position, value_type&& __x)
919 { return _M_t._M_insert_unique_(__position, std::move(__x)); }
920
921 template<typename _Pair>
922 __enable_if_t<is_constructible<value_type, _Pair>::value, iterator>
923 insert(const_iterator __position, _Pair&& __x)
924 {
925 return _M_t._M_emplace_hint_unique(__position,
926 std::forward<_Pair>(__x));
927 }
928#endif
929 /// @}
930
931 /**
932 * @brief Template function that attempts to insert a range of elements.
933 * @param __first Iterator pointing to the start of the range to be
934 * inserted.
935 * @param __last Iterator pointing to the end of the range.
936 *
937 * Complexity similar to that of the range constructor.
938 */
939 template<typename _InputIterator>
940 void
941 insert(_InputIterator __first, _InputIterator __last)
942 { _M_t._M_insert_range_unique(__first, __last); }
943
944#if __cplusplus > 201402L
945 /**
946 * @brief Attempts to insert or assign a std::pair into the %map.
947 * @param __k Key to use for finding a possibly existing pair in
948 * the map.
949 * @param __obj Argument used to generate the .second for a pair
950 * instance.
951 *
952 * @return A pair, of which the first element is an iterator that
953 * points to the possibly inserted pair, and the second is
954 * a bool that is true if the pair was actually inserted.
955 *
956 * This function attempts to insert a (key, value) %pair into the %map.
957 * A %map relies on unique keys and thus a %pair is only inserted if its
958 * first element (the key) is not already present in the %map.
959 * If the %pair was already in the %map, the .second of the %pair
960 * is assigned from __obj.
961 *
962 * Insertion requires logarithmic time.
963 */
964 template <typename _Obj>
966 insert_or_assign(const key_type& __k, _Obj&& __obj)
967 {
968 iterator __i = lower_bound(__k);
969 if (__i == end() || key_comp()(__k, (*__i).first))
970 {
974 std::forward<_Obj>(__obj)));
975 return {__i, true};
976 }
977 (*__i).second = std::forward<_Obj>(__obj);
978 return {__i, false};
979 }
980
981 // move-capable overload
982 template <typename _Obj>
984 insert_or_assign(key_type&& __k, _Obj&& __obj)
985 {
986 iterator __i = lower_bound(__k);
987 if (__i == end() || key_comp()(__k, (*__i).first))
988 {
992 std::forward<_Obj>(__obj)));
993 return {__i, true};
994 }
995 (*__i).second = std::forward<_Obj>(__obj);
996 return {__i, false};
997 }
998
999 /**
1000 * @brief Attempts to insert or assign a std::pair into the %map.
1001 * @param __hint An iterator that serves as a hint as to where the
1002 * pair should be inserted.
1003 * @param __k Key to use for finding a possibly existing pair in
1004 * the map.
1005 * @param __obj Argument used to generate the .second for a pair
1006 * instance.
1007 *
1008 * @return An iterator that points to the element with key of
1009 * @a __x (may or may not be the %pair passed in).
1010 *
1011 * This function attempts to insert a (key, value) %pair into the %map.
1012 * A %map relies on unique keys and thus a %pair is only inserted if its
1013 * first element (the key) is not already present in the %map.
1014 * If the %pair was already in the %map, the .second of the %pair
1015 * is assigned from __obj.
1016 *
1017 * Insertion requires logarithmic time.
1018 */
1019 template <typename _Obj>
1020 iterator
1021 insert_or_assign(const_iterator __hint,
1022 const key_type& __k, _Obj&& __obj)
1023 {
1024 iterator __i;
1025 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
1026 if (__true_hint.second)
1027 {
1028 return emplace_hint(iterator(__true_hint.second),
1032 std::forward<_Obj>(__obj)));
1033 }
1034 __i = iterator(__true_hint.first);
1035 (*__i).second = std::forward<_Obj>(__obj);
1036 return __i;
1037 }
1038
1039 // move-capable overload
1040 template <typename _Obj>
1041 iterator
1042 insert_or_assign(const_iterator __hint, key_type&& __k, _Obj&& __obj)
1043 {
1044 iterator __i;
1045 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
1046 if (__true_hint.second)
1047 {
1048 return emplace_hint(iterator(__true_hint.second),
1052 std::forward<_Obj>(__obj)));
1053 }
1054 __i = iterator(__true_hint.first);
1055 (*__i).second = std::forward<_Obj>(__obj);
1056 return __i;
1057 }
1058#endif
1059
1060#if __cplusplus >= 201103L
1061 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1062 // DR 130. Associative erase should return an iterator.
1063 /**
1064 * @brief Erases an element from a %map.
1065 * @param __position An iterator pointing to the element to be erased.
1066 * @return An iterator pointing to the element immediately following
1067 * @a position prior to the element being erased. If no such
1068 * element exists, end() is returned.
1069 *
1070 * This function erases an element, pointed to by the given
1071 * iterator, from a %map. Note that this function only erases
1072 * the element, and that if the element is itself a pointer,
1073 * the pointed-to memory is not touched in any way. Managing
1074 * the pointer is the user's responsibility.
1075 *
1076 * @{
1077 */
1078 iterator
1079 erase(const_iterator __position)
1080 { return _M_t.erase(__position); }
1081
1082 // LWG 2059
1083 _GLIBCXX_ABI_TAG_CXX11
1084 iterator
1085 erase(iterator __position)
1086 { return _M_t.erase(__position); }
1087 /// @}
1088#else
1089 /**
1090 * @brief Erases an element from a %map.
1091 * @param __position An iterator pointing to the element to be erased.
1092 *
1093 * This function erases an element, pointed to by the given
1094 * iterator, from a %map. Note that this function only erases
1095 * the element, and that if the element is itself a pointer,
1096 * the pointed-to memory is not touched in any way. Managing
1097 * the pointer is the user's responsibility.
1098 */
1099 void
1100 erase(iterator __position)
1101 { _M_t.erase(__position); }
1102#endif
1103
1104 /**
1105 * @brief Erases elements according to the provided key.
1106 * @param __x Key of element to be erased.
1107 * @return The number of elements erased.
1108 *
1109 * This function erases all the elements located by the given key from
1110 * a %map.
1111 * Note that this function only erases the element, and that if
1112 * the element is itself a pointer, the pointed-to memory is not touched
1113 * in any way. Managing the pointer is the user's responsibility.
1114 */
1115 size_type
1116 erase(const key_type& __x)
1117 { return _M_t.erase(__x); }
1118
1119#if __cplusplus >= 201103L
1120 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1121 // DR 130. Associative erase should return an iterator.
1122 /**
1123 * @brief Erases a [first,last) range of elements from a %map.
1124 * @param __first Iterator pointing to the start of the range to be
1125 * erased.
1126 * @param __last Iterator pointing to the end of the range to
1127 * be erased.
1128 * @return The iterator @a __last.
1129 *
1130 * This function erases a sequence of elements from a %map.
1131 * Note that this function only erases the element, and that if
1132 * the element is itself a pointer, the pointed-to memory is not touched
1133 * in any way. Managing the pointer is the user's responsibility.
1134 */
1135 iterator
1136 erase(const_iterator __first, const_iterator __last)
1137 { return _M_t.erase(__first, __last); }
1138#else
1139 /**
1140 * @brief Erases a [__first,__last) range of elements from a %map.
1141 * @param __first Iterator pointing to the start of the range to be
1142 * erased.
1143 * @param __last Iterator pointing to the end of the range to
1144 * be erased.
1145 *
1146 * This function erases a sequence of elements from a %map.
1147 * Note that this function only erases the element, and that if
1148 * the element is itself a pointer, the pointed-to memory is not touched
1149 * in any way. Managing the pointer is the user's responsibility.
1150 */
1151 void
1152 erase(iterator __first, iterator __last)
1153 { _M_t.erase(__first, __last); }
1154#endif
1155
1156 /**
1157 * @brief Swaps data with another %map.
1158 * @param __x A %map of the same element and allocator types.
1159 *
1160 * This exchanges the elements between two maps in constant
1161 * time. (It is only swapping a pointer, an integer, and an
1162 * instance of the @c Compare type (which itself is often
1163 * stateless and empty), so it should be quite fast.) Note
1164 * that the global std::swap() function is specialized such
1165 * that std::swap(m1,m2) will feed to this function.
1166 *
1167 * Whether the allocators are swapped depends on the allocator traits.
1168 */
1169 void
1170 swap(map& __x)
1171 _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
1172 { _M_t.swap(__x._M_t); }
1173
1174 /**
1175 * Erases all elements in a %map. Note that this function only
1176 * erases the elements, and that if the elements themselves are
1177 * pointers, the pointed-to memory is not touched in any way.
1178 * Managing the pointer is the user's responsibility.
1179 */
1180 void
1181 clear() _GLIBCXX_NOEXCEPT
1182 { _M_t.clear(); }
1183
1184 // observers
1185 /**
1186 * Returns the key comparison object out of which the %map was
1187 * constructed.
1188 */
1189 key_compare
1190 key_comp() const
1191 { return _M_t.key_comp(); }
1192
1193 /**
1194 * Returns a value comparison object, built from the key comparison
1195 * object out of which the %map was constructed.
1196 */
1197 value_compare
1199 { return value_compare(_M_t.key_comp()); }
1200
1201 // [23.3.1.3] map operations
1202
1203 ///@{
1204 /**
1205 * @brief Tries to locate an element in a %map.
1206 * @param __x Key of (key, value) %pair to be located.
1207 * @return Iterator pointing to sought-after element, or end() if not
1208 * found.
1209 *
1210 * This function takes a key and tries to locate the element with which
1211 * the key matches. If successful the function returns an iterator
1212 * pointing to the sought after %pair. If unsuccessful it returns the
1213 * past-the-end ( @c end() ) iterator.
1214 */
1215
1216 iterator
1217 find(const key_type& __x)
1218 { return _M_t.find(__x); }
1219
1220#if __cplusplus > 201103L
1221 template<typename _Kt>
1222 auto
1223 find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
1224 { return _M_t._M_find_tr(__x); }
1225#endif
1226 ///@}
1227
1228 ///@{
1229 /**
1230 * @brief Tries to locate an element in a %map.
1231 * @param __x Key of (key, value) %pair to be located.
1232 * @return Read-only (constant) iterator pointing to sought-after
1233 * element, or end() if not found.
1234 *
1235 * This function takes a key and tries to locate the element with which
1236 * the key matches. If successful the function returns a constant
1237 * iterator pointing to the sought after %pair. If unsuccessful it
1238 * returns the past-the-end ( @c end() ) iterator.
1239 */
1240
1241 const_iterator
1242 find(const key_type& __x) const
1243 { return _M_t.find(__x); }
1244
1245#if __cplusplus > 201103L
1246 template<typename _Kt>
1247 auto
1248 find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
1249 { return _M_t._M_find_tr(__x); }
1250#endif
1251 ///@}
1252
1253 ///@{
1254 /**
1255 * @brief Finds the number of elements with given key.
1256 * @param __x Key of (key, value) pairs to be located.
1257 * @return Number of elements with specified key.
1258 *
1259 * This function only makes sense for multimaps; for map the result will
1260 * either be 0 (not present) or 1 (present).
1261 */
1262 size_type
1263 count(const key_type& __x) const
1264 { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
1265
1266#if __cplusplus > 201103L
1267 template<typename _Kt>
1268 auto
1269 count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
1270 { return _M_t._M_count_tr(__x); }
1271#endif
1272 ///@}
1273
1274#if __cplusplus > 201703L
1275 ///@{
1276 /**
1277 * @brief Finds whether an element with the given key exists.
1278 * @param __x Key of (key, value) pairs to be located.
1279 * @return True if there is an element with the specified key.
1280 */
1281 bool
1282 contains(const key_type& __x) const
1283 { return _M_t.find(__x) != _M_t.end(); }
1284
1285 template<typename _Kt>
1286 auto
1287 contains(const _Kt& __x) const
1288 -> decltype(_M_t._M_find_tr(__x), void(), true)
1289 { return _M_t._M_find_tr(__x) != _M_t.end(); }
1290 ///@}
1291#endif
1292
1293 ///@{
1294 /**
1295 * @brief Finds the beginning of a subsequence matching given key.
1296 * @param __x Key of (key, value) pair to be located.
1297 * @return Iterator pointing to first element equal to or greater
1298 * than key, or end().
1299 *
1300 * This function returns the first element of a subsequence of elements
1301 * that matches the given key. If unsuccessful it returns an iterator
1302 * pointing to the first element that has a greater value than given key
1303 * or end() if no such element exists.
1304 */
1305 iterator
1306 lower_bound(const key_type& __x)
1307 { return _M_t.lower_bound(__x); }
1308
1309#if __cplusplus > 201103L
1310 template<typename _Kt>
1311 auto
1312 lower_bound(const _Kt& __x)
1313 -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
1314 { return iterator(_M_t._M_lower_bound_tr(__x)); }
1315#endif
1316 ///@}
1317
1318 ///@{
1319 /**
1320 * @brief Finds the beginning of a subsequence matching given key.
1321 * @param __x Key of (key, value) pair to be located.
1322 * @return Read-only (constant) iterator pointing to first element
1323 * equal to or greater than key, or end().
1324 *
1325 * This function returns the first element of a subsequence of elements
1326 * that matches the given key. If unsuccessful it returns an iterator
1327 * pointing to the first element that has a greater value than given key
1328 * or end() if no such element exists.
1329 */
1330 const_iterator
1331 lower_bound(const key_type& __x) const
1332 { return _M_t.lower_bound(__x); }
1333
1334#if __cplusplus > 201103L
1335 template<typename _Kt>
1336 auto
1337 lower_bound(const _Kt& __x) const
1338 -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
1339 { return const_iterator(_M_t._M_lower_bound_tr(__x)); }
1340#endif
1341 ///@}
1342
1343 ///@{
1344 /**
1345 * @brief Finds the end of a subsequence matching given key.
1346 * @param __x Key of (key, value) pair to be located.
1347 * @return Iterator pointing to the first element
1348 * greater than key, or end().
1349 */
1350 iterator
1351 upper_bound(const key_type& __x)
1352 { return _M_t.upper_bound(__x); }
1353
1354#if __cplusplus > 201103L
1355 template<typename _Kt>
1356 auto
1357 upper_bound(const _Kt& __x)
1358 -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
1359 { return iterator(_M_t._M_upper_bound_tr(__x)); }
1360#endif
1361 ///@}
1362
1363 ///@{
1364 /**
1365 * @brief Finds the end of a subsequence matching given key.
1366 * @param __x Key of (key, value) pair to be located.
1367 * @return Read-only (constant) iterator pointing to first iterator
1368 * greater than key, or end().
1369 */
1370 const_iterator
1371 upper_bound(const key_type& __x) const
1372 { return _M_t.upper_bound(__x); }
1373
1374#if __cplusplus > 201103L
1375 template<typename _Kt>
1376 auto
1377 upper_bound(const _Kt& __x) const
1378 -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
1379 { return const_iterator(_M_t._M_upper_bound_tr(__x)); }
1380#endif
1381 ///@}
1382
1383 ///@{
1384 /**
1385 * @brief Finds a subsequence matching given key.
1386 * @param __x Key of (key, value) pairs to be located.
1387 * @return Pair of iterators that possibly points to the subsequence
1388 * matching given key.
1389 *
1390 * This function is equivalent to
1391 * @code
1392 * std::make_pair(c.lower_bound(val),
1393 * c.upper_bound(val))
1394 * @endcode
1395 * (but is faster than making the calls separately).
1396 *
1397 * This function probably only makes sense for multimaps.
1398 */
1400 equal_range(const key_type& __x)
1401 { return _M_t.equal_range(__x); }
1402
1403#if __cplusplus > 201103L
1404 template<typename _Kt>
1405 auto
1406 equal_range(const _Kt& __x)
1407 -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
1408 { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
1409#endif
1410 ///@}
1411
1412 ///@{
1413 /**
1414 * @brief Finds a subsequence matching given key.
1415 * @param __x Key of (key, value) pairs to be located.
1416 * @return Pair of read-only (constant) iterators that possibly points
1417 * to the subsequence matching given key.
1418 *
1419 * This function is equivalent to
1420 * @code
1421 * std::make_pair(c.lower_bound(val),
1422 * c.upper_bound(val))
1423 * @endcode
1424 * (but is faster than making the calls separately).
1425 *
1426 * This function probably only makes sense for multimaps.
1427 */
1429 equal_range(const key_type& __x) const
1430 { return _M_t.equal_range(__x); }
1431
1432#if __cplusplus > 201103L
1433 template<typename _Kt>
1434 auto
1435 equal_range(const _Kt& __x) const
1437 _M_t._M_equal_range_tr(__x)))
1438 {
1440 _M_t._M_equal_range_tr(__x));
1441 }
1442#endif
1443 ///@}
1444
1445 template<typename _K1, typename _T1, typename _C1, typename _A1>
1446 friend bool
1447 operator==(const map<_K1, _T1, _C1, _A1>&,
1449
1450#if __cpp_lib_three_way_comparison
1451 template<typename _K1, typename _T1, typename _C1, typename _A1>
1452 friend __detail::__synth3way_t<pair<const _K1, _T1>>
1453 operator<=>(const map<_K1, _T1, _C1, _A1>&,
1455#else
1456 template<typename _K1, typename _T1, typename _C1, typename _A1>
1457 friend bool
1458 operator<(const map<_K1, _T1, _C1, _A1>&,
1460#endif
1461 };
1462
1463
1464#if __cpp_deduction_guides >= 201606
1465
1466 template<typename _InputIterator,
1467 typename _Compare = less<__iter_key_t<_InputIterator>>,
1468 typename _Allocator = allocator<__iter_to_alloc_t<_InputIterator>>,
1469 typename = _RequireInputIter<_InputIterator>,
1470 typename = _RequireNotAllocator<_Compare>,
1471 typename = _RequireAllocator<_Allocator>>
1472 map(_InputIterator, _InputIterator,
1473 _Compare = _Compare(), _Allocator = _Allocator())
1474 -> map<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1475 _Compare, _Allocator>;
1476
1477 template<typename _Key, typename _Tp, typename _Compare = less<_Key>,
1478 typename _Allocator = allocator<pair<const _Key, _Tp>>,
1479 typename = _RequireNotAllocator<_Compare>,
1480 typename = _RequireAllocator<_Allocator>>
1481 map(initializer_list<pair<_Key, _Tp>>,
1482 _Compare = _Compare(), _Allocator = _Allocator())
1483 -> map<_Key, _Tp, _Compare, _Allocator>;
1484
1485 template <typename _InputIterator, typename _Allocator,
1486 typename = _RequireInputIter<_InputIterator>,
1487 typename = _RequireAllocator<_Allocator>>
1488 map(_InputIterator, _InputIterator, _Allocator)
1489 -> map<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1490 less<__iter_key_t<_InputIterator>>, _Allocator>;
1491
1492 template<typename _Key, typename _Tp, typename _Allocator,
1493 typename = _RequireAllocator<_Allocator>>
1494 map(initializer_list<pair<_Key, _Tp>>, _Allocator)
1495 -> map<_Key, _Tp, less<_Key>, _Allocator>;
1496
1497#endif // deduction guides
1498
1499 /**
1500 * @brief Map equality comparison.
1501 * @param __x A %map.
1502 * @param __y A %map of the same type as @a x.
1503 * @return True iff the size and elements of the maps are equal.
1504 *
1505 * This is an equivalence relation. It is linear in the size of the
1506 * maps. Maps are considered equivalent if their sizes are equal,
1507 * and if corresponding elements compare equal.
1508 */
1509 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1510 inline bool
1513 { return __x._M_t == __y._M_t; }
1514
1515#if __cpp_lib_three_way_comparison
1516 /**
1517 * @brief Map ordering relation.
1518 * @param __x A `map`.
1519 * @param __y A `map` of the same type as `x`.
1520 * @return A value indicating whether `__x` is less than, equal to,
1521 * greater than, or incomparable with `__y`.
1522 *
1523 * This is a total ordering relation. It is linear in the size of the
1524 * maps. The elements must be comparable with @c <.
1525 *
1526 * See `std::lexicographical_compare_three_way()` for how the determination
1527 * is made. This operator is used to synthesize relational operators like
1528 * `<` and `>=` etc.
1529 */
1530 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1531 inline __detail::__synth3way_t<pair<const _Key, _Tp>>
1532 operator<=>(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1533 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1534 { return __x._M_t <=> __y._M_t; }
1535#else
1536 /**
1537 * @brief Map ordering relation.
1538 * @param __x A %map.
1539 * @param __y A %map of the same type as @a x.
1540 * @return True iff @a x is lexicographically less than @a y.
1541 *
1542 * This is a total ordering relation. It is linear in the size of the
1543 * maps. The elements must be comparable with @c <.
1544 *
1545 * See std::lexicographical_compare() for how the determination is made.
1546 */
1547 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1548 inline bool
1549 operator<(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1551 { return __x._M_t < __y._M_t; }
1552
1553 /// Based on operator==
1554 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1555 inline bool
1558 { return !(__x == __y); }
1559
1560 /// Based on operator<
1561 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1562 inline bool
1565 { return __y < __x; }
1566
1567 /// Based on operator<
1568 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1569 inline bool
1570 operator<=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1572 { return !(__y < __x); }
1573
1574 /// Based on operator<
1575 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1576 inline bool
1579 { return !(__x < __y); }
1580#endif // three-way comparison
1581
1582 /// See std::map::swap().
1583 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1584 inline void
1587 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
1588 { __x.swap(__y); }
1589
1590_GLIBCXX_END_NAMESPACE_CONTAINER
1591
1592#if __cplusplus > 201402L
1593 // Allow std::map access to internals of compatible maps.
1594 template<typename _Key, typename _Val, typename _Cmp1, typename _Alloc,
1595 typename _Cmp2>
1596 struct
1597 _Rb_tree_merge_helper<_GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>,
1598 _Cmp2>
1599 {
1600 private:
1601 friend class _GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>;
1602
1603 static auto&
1604 _S_get_tree(_GLIBCXX_STD_C::map<_Key, _Val, _Cmp2, _Alloc>& __map)
1605 { return __map._M_t; }
1606
1607 static auto&
1608 _S_get_tree(_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp2, _Alloc>& __map)
1609 { return __map._M_t; }
1610 };
1611#endif // C++17
1612
1613_GLIBCXX_END_NAMESPACE_VERSION
1614} // namespace std
1615
1616#endif /* _STL_MAP_H */
typename remove_reference< _Tp >::type remove_reference_t
Alias template for remove_reference.
Definition: type_traits:1598
constexpr tuple< _Elements &&... > forward_as_tuple(_Elements &&... __args) noexcept
std::forward_as_tuple
Definition: tuple:1997
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Definition: move.h:104
constexpr piecewise_construct_t piecewise_construct
Tag for piecewise construction of std::pair objects.
Definition: stl_pair.h:83
void swap(any &__x, any &__y) noexcept
Exchange the states of two any objects.
Definition: any:429
ISO C++ entities toplevel namespace is std.
initializer_list
Primary class template, tuple.
Definition: tuple:746
is_scalar
Definition: type_traits:655
is_same
Definition: type_traits:1369
is_nothrow_copy_constructible
Definition: type_traits:1103
Node handle type for maps.
Definition: node_handle.h:240
Return type of insert(node_handle&&) on unique maps/sets.
Definition: node_handle.h:382
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:189
_T1 first
The first member.
Definition: stl_pair.h:193
constexpr void swap(pair &__p) noexcept(__and_< __is_nothrow_swappable< _T1 >, __is_nothrow_swappable< _T2 > >::value)
Swap the first members and then the second members.
Definition: stl_pair.h:206
Common iterator class.
A standard container made up of (key,value) pairs, which can be retrieved based on a key,...
Definition: stl_map.h:101
iterator emplace_hint(const_iterator __pos, _Args &&... __args)
Attempts to build and insert a std::pair into the map.
Definition: stl_map.h:636
const_iterator find(const key_type &__x) const
Tries to locate an element in a map.
Definition: stl_map.h:1242
map(_InputIterator __first, _InputIterator __last, const allocator_type &__a)
Allocator-extended range constructor.
Definition: stl_map.h:266
__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:923
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:1269
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:1435
bool empty() const noexcept
Definition: stl_map.h:475
const_reverse_iterator rend() const noexcept
Definition: stl_map.h:429
bool contains(const key_type &__x) const
Finds whether an element with the given key exists.
Definition: stl_map.h:1282
~map()=default
map(const map &__m, const __type_identity_t< allocator_type > &__a)
Allocator-extended copy constructor.
Definition: stl_map.h:250
value_compare value_comp() const
Definition: stl_map.h:1198
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:1337
pair< iterator, bool > try_emplace(const key_type &__k, _Args &&... __args)
Attempts to build and insert a std::pair into the map.
Definition: stl_map.h:721
void insert(_InputIterator __first, _InputIterator __last)
Template function that attempts to insert a range of elements.
Definition: stl_map.h:941
iterator upper_bound(const key_type &__x)
Finds the end of a subsequence matching given key.
Definition: stl_map.h:1351
std::pair< iterator, iterator > equal_range(const key_type &__x)
Finds a subsequence matching given key.
Definition: stl_map.h:1400
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:238
insert_return_type insert(node_type &&__nh)
Re-insert an extracted node.
Definition: stl_map.h:659
auto find(const _Kt &__x) -> decltype(_M_t._M_find_tr(__x))
Tries to locate an element in a map.
Definition: stl_map.h:1223
iterator try_emplace(const_iterator __hint, const key_type &__k, _Args &&... __args)
Attempts to build and insert a std::pair into the map.
Definition: stl_map.h:781
std::pair< iterator, bool > insert(const value_type &__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:833
map(map &&)=default
Map move constructor.
size_type count(const key_type &__x) const
Finds the number of elements with given key.
Definition: stl_map.h:1263
const_reverse_iterator rbegin() const noexcept
Definition: stl_map.h:411
reverse_iterator rbegin() noexcept
Definition: stl_map.h:402
iterator insert_or_assign(const_iterator __hint, const key_type &__k, _Obj &&__obj)
Attempts to insert or assign a std::pair into the map.
Definition: stl_map.h:1021
const_iterator end() const noexcept
Definition: stl_map.h:393
const_iterator cend() const noexcept
Definition: stl_map.h:448
mapped_type & at(const key_type &__k)
Access to map data.
Definition: stl_map.h:547
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:1357
key_compare key_comp() const
Definition: stl_map.h:1190
map(map &&__m, const __type_identity_t< allocator_type > &__a) noexcept(is_nothrow_copy_constructible< _Compare >::value &&_Alloc_traits::_S_always_equal())
Allocator-extended move constructor.
Definition: stl_map.h:254
void clear() noexcept
Definition: stl_map.h:1181
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:1312
iterator end() noexcept
Definition: stl_map.h:384
map(_InputIterator __first, _InputIterator __last)
Builds a map from a range.
Definition: stl_map.h:283
const_reverse_iterator crbegin() const noexcept
Definition: stl_map.h:457
pair< iterator, bool > insert_or_assign(const key_type &__k, _Obj &&__obj)
Attempts to insert or assign a std::pair into the map.
Definition: stl_map.h:966
void swap(map &__x) noexcept(/*conditional */)
Swaps data with another map.
Definition: stl_map.h:1170
size_type erase(const key_type &__x)
Erases elements according to the provided key.
Definition: stl_map.h:1116
iterator insert(const_iterator __hint, node_type &&__nh)
Re-insert an extracted node.
Definition: stl_map.h:664
map(initializer_list< value_type > __l, const allocator_type &__a)
Allocator-extended initialier-list constructor.
Definition: stl_map.h:260
map(const map &)=default
Map copy constructor.
node_type extract(const_iterator __pos)
Extract a node.
Definition: stl_map.h:646
map(const allocator_type &__a)
Allocator-extended default constructor.
Definition: stl_map.h:246
node_type extract(const key_type &__x)
Extract a node.
Definition: stl_map.h:654
iterator insert(const_iterator __position, value_type &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:918
iterator insert(const_iterator __position, const value_type &__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:908
map(const _Compare &__comp, const allocator_type &__a=allocator_type())
Creates a map with no elements.
Definition: stl_map.h:204
reverse_iterator rend() noexcept
Definition: stl_map.h:420
iterator erase(const_iterator __first, const_iterator __last)
Erases a [first,last) range of elements from a map.
Definition: stl_map.h:1136
void insert(std::initializer_list< value_type > __list)
Attempts to insert a list of std::pairs into the map.
Definition: stl_map.h:878
map & operator=(const map &)=default
Map assignment operator.
const_iterator lower_bound(const key_type &__x) const
Finds the beginning of a subsequence matching given key.
Definition: stl_map.h:1331
size_type size() const noexcept
Definition: stl_map.h:480
std::pair< const_iterator, const_iterator > equal_range(const key_type &__x) const
Finds a subsequence matching given key.
Definition: stl_map.h:1429
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:1377
iterator find(const key_type &__x)
Tries to locate an element in a map.
Definition: stl_map.h:1217
map(_InputIterator __first, _InputIterator __last, const _Compare &__comp, const allocator_type &__a=allocator_type())
Builds a map from a range.
Definition: stl_map.h:300
__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:846
iterator erase(const_iterator __position)
Erases an element from a map.
Definition: stl_map.h:1079
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:1248
mapped_type & operator[](const key_type &__k)
Subscript ( [] ) access to map data.
Definition: stl_map.h:502
auto contains(const _Kt &__x) const -> decltype(_M_t._M_find_tr(__x), void(), true)
Finds whether an element with the given key exists.
Definition: stl_map.h:1287
iterator lower_bound(const key_type &__x)
Finds the beginning of a subsequence matching given key.
Definition: stl_map.h:1306
const_reverse_iterator crend() const noexcept
Definition: stl_map.h:466
allocator_type get_allocator() const noexcept
Get a copy of the memory allocation object.
Definition: stl_map.h:356
map & operator=(initializer_list< value_type > __l)
Map list assignment operator.
Definition: stl_map.h:347
_GLIBCXX_ABI_TAG_CXX11 iterator erase(iterator __position)
Erases an element from a map.
Definition: stl_map.h:1085
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:1406
std::pair< iterator, bool > emplace(_Args &&... __args)
Attempts to build and insert a std::pair into the map.
Definition: stl_map.h:586
const_iterator cbegin() const noexcept
Definition: stl_map.h:439
size_type max_size() const noexcept
Definition: stl_map.h:485
const_iterator begin() const noexcept
Definition: stl_map.h:375
iterator begin() noexcept
Definition: stl_map.h:366
map & operator=(map &&)=default
Move assignment operator.
std::pair< iterator, bool > insert(value_type &&__x)
Attempts to insert a std::pair into the map.
Definition: stl_map.h:840
map()=default
Default constructor creates no elements.
const_iterator upper_bound(const key_type &__x) const
Finds the end of a subsequence matching given key.
Definition: stl_map.h:1371
Uniform interface to C++98 and C++11 allocators.