1// Map implementation -*- C++ -*-
2
3// Copyright (C) 2001-2024 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
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
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 * @headerfile map
80 * @since C++98
81 *
82 * @tparam _Key Type of key objects.
83 * @tparam _Tp Type of mapped objects.
84 * @tparam _Compare Comparison function object type, defaults to less<_Key>.
85 * @tparam _Alloc Allocator type, defaults to
86 * allocator<pair<const _Key, _Tp>.
87 *
88 * Meets the requirements of a <a href="tables.html#65">container</a>, a
89 * <a href="tables.html#66">reversible container</a>, and an
90 * <a href="tables.html#69">associative container</a> (using unique keys).
91 * For a @c map<Key,T> the key_type is Key, the mapped_type is T, and the
92 * value_type is std::pair<const Key,T>.
93 *
94 * Maps support bidirectional iterators.
95 *
96 * The private tree data is declared exactly the same way for map and
97 * multimap; the distinction is made entirely in how the tree functions are
98 * called (*_unique versus *_equal, same as the standard).
99 */
100 template <typename _Key, typename _Tp, typename _Compare = std::less<_Key>,
101 typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
102 class map
103 {
104 public:
105 typedef _Key key_type;
106 typedef _Tp mapped_type;
107 typedef std::pair<const _Key, _Tp> value_type;
108 typedef _Compare key_compare;
109 typedef _Alloc allocator_type;
110
111 private:
112#ifdef _GLIBCXX_CONCEPT_CHECKS
113 // concept requirements
114 typedef typename _Alloc::value_type _Alloc_value_type;
115# if __cplusplus < 201103L
116 __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
117# endif
118 __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
119 _BinaryFunctionConcept)
120 __glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept)
121#endif
122
123#if __cplusplus >= 201103L
124#if __cplusplus > 201703L || defined __STRICT_ANSI__
125 static_assert(is_same<typename _Alloc::value_type, value_type>::value,
126 "std::map must have the same value_type as its allocator");
127#endif
128#endif
129
130 public:
131#pragma GCC diagnostic push
132#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
133 class value_compare
134 : public std::binary_function<value_type, value_type, bool>
135 {
136 friend class map<_Key, _Tp, _Compare, _Alloc>;
137 protected:
138 _Compare comp;
139
140 value_compare(_Compare __c)
141 : comp(__c) { }
142
143 public:
144 bool operator()(const value_type& __x, const value_type& __y) const
145 { return comp(__x.first, __y.first); }
146 };
147#pragma GCC diagnostic pop
148
149 private:
150 /// This turns a red-black tree into a [multi]map.
151 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
152 rebind<value_type>::other _Pair_alloc_type;
153
154 typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
155 key_compare, _Pair_alloc_type> _Rep_type;
156
157 /// The actual tree structure.
158 _Rep_type _M_t;
159
160 typedef __gnu_cxx::__alloc_traits<_Pair_alloc_type> _Alloc_traits;
161
162#if __cplusplus >= 201703L
163 template<typename _Up, typename _Vp = remove_reference_t<_Up>>
164 static constexpr bool __usable_key
165 = __or_v<is_same<const _Vp, const _Key>,
166 __and_<is_scalar<_Vp>, is_scalar<_Key>>>;
167#endif
168
169 public:
170 // many of these are specified differently in ISO, but the following are
171 // "functionally equivalent"
172 typedef typename _Alloc_traits::pointer pointer;
173 typedef typename _Alloc_traits::const_pointer const_pointer;
174 typedef typename _Alloc_traits::reference reference;
175 typedef typename _Alloc_traits::const_reference const_reference;
176 typedef typename _Rep_type::iterator iterator;
177 typedef typename _Rep_type::const_iterator const_iterator;
178 typedef typename _Rep_type::size_type size_type;
179 typedef typename _Rep_type::difference_type difference_type;
180 typedef typename _Rep_type::reverse_iterator reverse_iterator;
181 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
182
183#if __cplusplus > 201402L
184 using node_type = typename _Rep_type::node_type;
185 using insert_return_type = typename _Rep_type::insert_return_type;
186#endif
187
188 // [23.3.1.1] construct/copy/destroy
189 // (get_allocator() is also listed in this section)
190
191 /**
192 * @brief Default constructor creates no elements.
193 */
194#if __cplusplus < 201103L
195 map() : _M_t() { }
196#else
197 map() = default;
198#endif
199
200 /**
201 * @brief Creates a %map with no elements.
202 * @param __comp A comparison object.
203 * @param __a An allocator object.
204 */
205 explicit
206 map(const _Compare& __comp,
207 const allocator_type& __a = allocator_type())
208 : _M_t(__comp, _Pair_alloc_type(__a)) { }
209
210 /**
211 * @brief %Map copy constructor.
212 *
213 * Whether the allocator is copied depends on the allocator traits.
214 */
215#if __cplusplus < 201103L
216 map(const map& __x)
217 : _M_t(__x._M_t) { }
218#else
219 map(const map&) = default;
220
221 /**
222 * @brief %Map move constructor.
223 *
224 * The newly-created %map contains the exact contents of the moved
225 * instance. The moved instance is a valid, but unspecified, %map.
226 */
227 map(map&&) = default;
228
229 /**
230 * @brief Builds a %map from an initializer_list.
231 * @param __l An initializer_list.
232 * @param __comp A comparison object.
233 * @param __a An allocator object.
234 *
235 * Create a %map consisting of copies of the elements in the
236 * initializer_list @a __l.
237 * This is linear in N if the range is already sorted, and NlogN
238 * otherwise (where N is @a __l.size()).
239 */
240 map(initializer_list<value_type> __l,
241 const _Compare& __comp = _Compare(),
242 const allocator_type& __a = allocator_type())
243 : _M_t(__comp, _Pair_alloc_type(__a))
244 { _M_t._M_insert_range_unique(__l.begin(), __l.end()); }
245
246 /// Allocator-extended default constructor.
247 explicit
248 map(const allocator_type& __a)
249 : _M_t(_Pair_alloc_type(__a)) { }
250
251 /// Allocator-extended copy constructor.
252 map(const map& __m, const __type_identity_t<allocator_type>& __a)
253 : _M_t(__m._M_t, _Pair_alloc_type(__a)) { }
254
255 /// Allocator-extended move constructor.
256 map(map&& __m, const __type_identity_t<allocator_type>& __a)
257 noexcept(is_nothrow_copy_constructible<_Compare>::value
258 && _Alloc_traits::_S_always_equal())
259 : _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { }
260
261 /// Allocator-extended initialier-list constructor.
262 map(initializer_list<value_type> __l, const allocator_type& __a)
263 : _M_t(_Pair_alloc_type(__a))
264 { _M_t._M_insert_range_unique(__l.begin(), __l.end()); }
265
266 /// Allocator-extended range constructor.
267 template<typename _InputIterator>
268 map(_InputIterator __first, _InputIterator __last,
269 const allocator_type& __a)
270 : _M_t(_Pair_alloc_type(__a))
271 { _M_t._M_insert_range_unique(__first, __last); }
272#endif
273
274 /**
275 * @brief Builds a %map from a range.
276 * @param __first An input iterator.
277 * @param __last An input iterator.
278 *
279 * Create a %map consisting of copies of the elements from
280 * [__first,__last). This is linear in N if the range is
281 * already sorted, and NlogN otherwise (where N is
282 * distance(__first,__last)).
283 */
284 template<typename _InputIterator>
285 map(_InputIterator __first, _InputIterator __last)
286 : _M_t()
287 { _M_t._M_insert_range_unique(__first, __last); }
288
289 /**
290 * @brief Builds a %map from a range.
291 * @param __first An input iterator.
292 * @param __last An input iterator.
293 * @param __comp A comparison functor.
294 * @param __a An allocator object.
295 *
296 * Create a %map consisting of copies of the elements from
297 * [__first,__last). This is linear in N if the range is
298 * already sorted, and NlogN otherwise (where N is
299 * distance(__first,__last)).
300 */
301 template<typename _InputIterator>
302 map(_InputIterator __first, _InputIterator __last,
303 const _Compare& __comp,
304 const allocator_type& __a = allocator_type())
305 : _M_t(__comp, _Pair_alloc_type(__a))
306 { _M_t._M_insert_range_unique(__first, __last); }
307
308#if __cplusplus >= 201103L
309 /**
310 * The dtor only erases the elements, and note that if the elements
311 * themselves are pointers, the pointed-to memory is not touched in any
312 * way. Managing the pointer is the user's responsibility.
313 */
314 ~map() = default;
315#endif
316
317 /**
318 * @brief %Map assignment operator.
319 *
320 * Whether the allocator is copied depends on the allocator traits.
321 */
322#if __cplusplus < 201103L
323 map&
324 operator=(const map& __x)
325 {
326 _M_t = __x._M_t;
327 return *this;
328 }
329#else
330 map&
331 operator=(const map&) = default;
332
333 /// Move assignment operator.
334 map&
335 operator=(map&&) = default;
336
337 /**
338 * @brief %Map list assignment operator.
339 * @param __l An initializer_list.
340 *
341 * This function fills a %map with copies of the elements in the
342 * initializer list @a __l.
343 *
344 * Note that the assignment completely changes the %map and
345 * that the resulting %map's size is the same as the number
346 * of elements assigned.
347 */
348 map&
349 operator=(initializer_list<value_type> __l)
350 {
351 _M_t._M_assign_unique(__l.begin(), __l.end());
352 return *this;
353 }
354#endif
355
356 /// Get a copy of the memory allocation object.
357 allocator_type
358 get_allocator() const _GLIBCXX_NOEXCEPT
359 { return allocator_type(_M_t.get_allocator()); }
360
361 // iterators
362 /**
363 * Returns a read/write iterator that points to the first pair in the
364 * %map.
365 * Iteration is done in ascending order according to the keys.
366 */
367 iterator
368 begin() _GLIBCXX_NOEXCEPT
369 { return _M_t.begin(); }
370
371 /**
372 * Returns a read-only (constant) iterator that points to the first pair
373 * in the %map. Iteration is done in ascending order according to the
374 * keys.
375 */
376 const_iterator
377 begin() const _GLIBCXX_NOEXCEPT
378 { return _M_t.begin(); }
379
380 /**
381 * Returns a read/write iterator that points one past the last
382 * pair in the %map. Iteration is done in ascending order
383 * according to the keys.
384 */
385 iterator
386 end() _GLIBCXX_NOEXCEPT
387 { return _M_t.end(); }
388
389 /**
390 * Returns a read-only (constant) iterator that points one past the last
391 * pair in the %map. Iteration is done in ascending order according to
392 * the keys.
393 */
394 const_iterator
395 end() const _GLIBCXX_NOEXCEPT
396 { return _M_t.end(); }
397
398 /**
399 * Returns a read/write reverse iterator that points to the last pair in
400 * the %map. Iteration is done in descending order according to the
401 * keys.
402 */
403 reverse_iterator
404 rbegin() _GLIBCXX_NOEXCEPT
405 { return _M_t.rbegin(); }
406
407 /**
408 * Returns a read-only (constant) reverse iterator that points to the
409 * last pair in the %map. Iteration is done in descending order
410 * according to the keys.
411 */
412 const_reverse_iterator
413 rbegin() const _GLIBCXX_NOEXCEPT
414 { return _M_t.rbegin(); }
415
416 /**
417 * Returns a read/write reverse iterator that points to one before the
418 * first pair in the %map. Iteration is done in descending order
419 * according to the keys.
420 */
421 reverse_iterator
422 rend() _GLIBCXX_NOEXCEPT
423 { return _M_t.rend(); }
424
425 /**
426 * Returns a read-only (constant) reverse iterator that points to one
427 * before the first pair in the %map. Iteration is done in descending
428 * order according to the keys.
429 */
430 const_reverse_iterator
431 rend() const _GLIBCXX_NOEXCEPT
432 { return _M_t.rend(); }
433
434#if __cplusplus >= 201103L
435 /**
436 * Returns a read-only (constant) iterator that points to the first pair
437 * in the %map. Iteration is done in ascending order according to the
438 * keys.
439 */
440 const_iterator
441 cbegin() const noexcept
442 { return _M_t.begin(); }
443
444 /**
445 * Returns a read-only (constant) iterator that points one past the last
446 * pair in the %map. Iteration is done in ascending order according to
447 * the keys.
448 */
449 const_iterator
450 cend() const noexcept
451 { return _M_t.end(); }
452
453 /**
454 * Returns a read-only (constant) reverse iterator that points to the
455 * last pair in the %map. Iteration is done in descending order
456 * according to the keys.
457 */
458 const_reverse_iterator
459 crbegin() const noexcept
460 { return _M_t.rbegin(); }
461
462 /**
463 * Returns a read-only (constant) reverse iterator that points to one
464 * before the first pair in the %map. Iteration is done in descending
465 * order according to the keys.
466 */
467 const_reverse_iterator
468 crend() const noexcept
469 { return _M_t.rend(); }
470#endif
471
472 // capacity
473 /** Returns true if the %map is empty. (Thus begin() would equal
474 * end().)
475 */
476 _GLIBCXX_NODISCARD bool
477 empty() const _GLIBCXX_NOEXCEPT
478 { return _M_t.empty(); }
479
480 /** Returns the size of the %map. */
481 size_type
482 size() const _GLIBCXX_NOEXCEPT
483 { return _M_t.size(); }
484
485 /** Returns the maximum size of the %map. */
486 size_type
487 max_size() const _GLIBCXX_NOEXCEPT
488 { return _M_t.max_size(); }
489
490 // [23.3.1.2] element access
491 /**
492 * @brief Subscript ( @c [] ) access to %map data.
493 * @param __k The key for which data should be retrieved.
494 * @return A reference to the data of the (key,data) %pair.
495 *
496 * Allows for easy lookup with the subscript ( @c [] )
497 * operator. Returns data associated with the key specified in
498 * subscript. If the key does not exist, a pair with that key
499 * is created using default values, which is then returned.
500 *
501 * Lookup requires logarithmic time.
502 */
503 mapped_type&
504 operator[](const key_type& __k)
505 {
506 // concept requirements
507 __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
508
509 iterator __i = lower_bound(__k);
510 // __i->first is greater than or equivalent to __k.
511 if (__i == end() || key_comp()(__k, (*__i).first))
512#if __cplusplus >= 201103L
513 __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
514 std::tuple<const key_type&>(__k),
515 std::tuple<>());
516#else
517 __i = insert(__i, value_type(__k, mapped_type()));
518#endif
519 return (*__i).second;
520 }
521
522#if __cplusplus >= 201103L
523 mapped_type&
524 operator[](key_type&& __k)
525 {
526 // concept requirements
527 __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
528
529 iterator __i = lower_bound(__k);
530 // __i->first is greater than or equivalent to __k.
531 if (__i == end() || key_comp()(__k, (*__i).first))
532 __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
533 std::forward_as_tuple(std::move(__k)),
534 std::tuple<>());
535 return (*__i).second;
536 }
537#endif
538
539 // _GLIBCXX_RESOLVE_LIB_DEFECTS
540 // DR 464. Suggestion for new member functions in standard containers.
541 /**
542 * @brief Access to %map data.
543 * @param __k The key for which data should be retrieved.
544 * @return A reference to the data whose key is equivalent to @a __k, if
545 * such a data is present in the %map.
546 * @throw std::out_of_range If no such data is present.
547 */
548 mapped_type&
549 at(const key_type& __k)
550 {
551 iterator __i = lower_bound(__k);
552 if (__i == end() || key_comp()(__k, (*__i).first))
553 __throw_out_of_range(__N("map::at"));
554 return (*__i).second;
555 }
556
557 const mapped_type&
558 at(const key_type& __k) const
559 {
560 const_iterator __i = lower_bound(__k);
561 if (__i == end() || key_comp()(__k, (*__i).first))
562 __throw_out_of_range(__N("map::at"));
563 return (*__i).second;
564 }
565
566 // modifiers
567#if __cplusplus >= 201103L
568 /**
569 * @brief Attempts to build and insert a std::pair into the %map.
570 *
571 * @param __args Arguments used to generate a new pair instance (see
572 * std::piecewise_contruct for passing arguments to each
573 * part of the pair constructor).
574 *
575 * @return A pair, of which the first element is an iterator that points
576 * to the possibly inserted pair, and the second is a bool that
577 * is true if the pair was actually inserted.
578 *
579 * This function attempts to build and insert a (key, value) %pair into
580 * the %map.
581 * A %map relies on unique keys and thus a %pair is only inserted if its
582 * first element (the key) is not already present in the %map.
583 *
584 * Insertion requires logarithmic time.
585 */
586 template<typename... _Args>
587 std::pair<iterator, bool>
588 emplace(_Args&&... __args)
589 {
590#if __cplusplus >= 201703L
591 if constexpr (sizeof...(_Args) == 2)
592 if constexpr (is_same_v<allocator_type, allocator<value_type>>)
593 {
594 auto&& [__a, __v] = pair<_Args&...>(__args...);
595 if constexpr (__usable_key<decltype(__a)>)
596 {
597 const key_type& __k = __a;
598 iterator __i = lower_bound(__k);
599 if (__i == end() || key_comp()(__k, (*__i).first))
600 {
601 __i = emplace_hint(__i, std::forward<_Args>(__args)...);
602 return {__i, true};
603 }
604 return {__i, false};
605 }
606 }
607#endif
608 return _M_t._M_emplace_unique(std::forward<_Args>(__args)...);
609 }
610
611 /**
612 * @brief Attempts to build and insert a std::pair into the %map.
613 *
614 * @param __pos An iterator that serves as a hint as to where the pair
615 * should be inserted.
616 * @param __args Arguments used to generate a new pair instance (see
617 * std::piecewise_contruct for passing arguments to each
618 * part of the pair constructor).
619 * @return An iterator that points to the element with key of the
620 * std::pair built from @a __args (may or may not be that
621 * std::pair).
622 *
623 * This function is not concerned about whether the insertion took place,
624 * and thus does not return a boolean like the single-argument emplace()
625 * does.
626 * Note that the first parameter is only a hint and can potentially
627 * improve the performance of the insertion process. A bad hint would
628 * cause no gains in efficiency.
629 *
630 * See
631 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
632 * for more on @a hinting.
633 *
634 * Insertion requires logarithmic time (if the hint is not taken).
635 */
636 template<typename... _Args>
637 iterator
638 emplace_hint(const_iterator __pos, _Args&&... __args)
639 {
640 return _M_t._M_emplace_hint_unique(__pos,
641 std::forward<_Args>(__args)...);
642 }
643#endif
644
645#if __cplusplus > 201402L
646 /// Extract a node.
647 node_type
648 extract(const_iterator __pos)
649 {
650 __glibcxx_assert(__pos != end());
651 return _M_t.extract(__pos);
652 }
653
654 /// Extract a node.
655 node_type
656 extract(const key_type& __x)
657 { return _M_t.extract(__x); }
658
659 /// Re-insert an extracted node.
660 insert_return_type
661 insert(node_type&& __nh)
662 { return _M_t._M_reinsert_node_unique(std::move(__nh)); }
663
664 /// Re-insert an extracted node.
665 iterator
666 insert(const_iterator __hint, node_type&& __nh)
667 { return _M_t._M_reinsert_node_hint_unique(__hint, std::move(__nh)); }
668
669 template<typename, typename>
670 friend struct std::_Rb_tree_merge_helper;
671
672 template<typename _Cmp2>
673 void
674 merge(map<_Key, _Tp, _Cmp2, _Alloc>& __source)
675 {
676 using _Merge_helper = _Rb_tree_merge_helper<map, _Cmp2>;
677 _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
678 }
679
680 template<typename _Cmp2>
681 void
682 merge(map<_Key, _Tp, _Cmp2, _Alloc>&& __source)
683 { merge(__source); }
684
685 template<typename _Cmp2>
686 void
687 merge(multimap<_Key, _Tp, _Cmp2, _Alloc>& __source)
688 {
689 using _Merge_helper = _Rb_tree_merge_helper<map, _Cmp2>;
690 _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
691 }
692
693 template<typename _Cmp2>
694 void
695 merge(multimap<_Key, _Tp, _Cmp2, _Alloc>&& __source)
696 { merge(__source); }
697#endif // C++17
698
699#ifdef __glibcxx_map_try_emplace // C++ >= 17 && HOSTED
700 /**
701 * @brief Attempts to build and insert a std::pair into the %map.
702 *
703 * @param __k Key to use for finding a possibly existing pair in
704 * the map.
705 * @param __args Arguments used to generate the .second for a new pair
706 * instance.
707 *
708 * @return A pair, of which the first element is an iterator that points
709 * to the possibly inserted pair, and the second is a bool that
710 * is true if the pair was actually inserted.
711 *
712 * This function attempts to build and insert a (key, value) %pair into
713 * the %map.
714 * A %map relies on unique keys and thus a %pair is only inserted if its
715 * first element (the key) is not already present in the %map.
716 * If a %pair is not inserted, this function has no effect.
717 *
718 * Insertion requires logarithmic time.
719 */
720 template <typename... _Args>
721 pair<iterator, bool>
722 try_emplace(const key_type& __k, _Args&&... __args)
723 {
724 iterator __i = lower_bound(__k);
725 if (__i == end() || key_comp()(__k, (*__i).first))
726 {
727 __i = emplace_hint(__i, std::piecewise_construct,
728 std::forward_as_tuple(__k),
729 std::forward_as_tuple(
730 std::forward<_Args>(__args)...));
731 return {__i, true};
732 }
733 return {__i, false};
734 }
735
736 // move-capable overload
737 template <typename... _Args>
738 pair<iterator, bool>
739 try_emplace(key_type&& __k, _Args&&... __args)
740 {
741 iterator __i = lower_bound(__k);
742 if (__i == end() || key_comp()(__k, (*__i).first))
743 {
744 __i = emplace_hint(__i, std::piecewise_construct,
745 std::forward_as_tuple(std::move(__k)),
746 std::forward_as_tuple(
747 std::forward<_Args>(__args)...));
748 return {__i, true};
749 }
750 return {__i, false};
751 }
752
753 /**
754 * @brief Attempts to build and insert a std::pair into the %map.
755 *
756 * @param __hint An iterator that serves as a hint as to where the
757 * pair should be inserted.
758 * @param __k Key to use for finding a possibly existing pair in
759 * the map.
760 * @param __args Arguments used to generate the .second for a new pair
761 * instance.
762 * @return An iterator that points to the element with key of the
763 * std::pair built from @a __args (may or may not be that
764 * std::pair).
765 *
766 * This function is not concerned about whether the insertion took place,
767 * and thus does not return a boolean like the single-argument
768 * try_emplace() does. However, if insertion did not take place,
769 * this function has no effect.
770 * Note that the first parameter is only a hint and can potentially
771 * improve the performance of the insertion process. A bad hint would
772 * cause no gains in efficiency.
773 *
774 * See
775 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
776 * for more on @a hinting.
777 *
778 * Insertion requires logarithmic time (if the hint is not taken).
779 */
780 template <typename... _Args>
781 iterator
782 try_emplace(const_iterator __hint, const key_type& __k,
783 _Args&&... __args)
784 {
785 iterator __i;
786 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
787 if (__true_hint.second)
788 __i = emplace_hint(iterator(__true_hint.second),
789 std::piecewise_construct,
790 std::forward_as_tuple(__k),
791 std::forward_as_tuple(
792 std::forward<_Args>(__args)...));
793 else
794 __i = iterator(__true_hint.first);
795 return __i;
796 }
797
798 // move-capable overload
799 template <typename... _Args>
800 iterator
801 try_emplace(const_iterator __hint, key_type&& __k, _Args&&... __args)
802 {
803 iterator __i;
804 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
805 if (__true_hint.second)
806 __i = emplace_hint(iterator(__true_hint.second),
807 std::piecewise_construct,
808 std::forward_as_tuple(std::move(__k)),
809 std::forward_as_tuple(
810 std::forward<_Args>(__args)...));
811 else
812 __i = iterator(__true_hint.first);
813 return __i;
814 }
815#endif
816
817 /**
818 * @brief Attempts to insert a std::pair into the %map.
819 * @param __x Pair to be inserted (see std::make_pair for easy
820 * creation of pairs).
821 *
822 * @return A pair, of which the first element is an iterator that
823 * points to the possibly inserted pair, and the second is
824 * a bool that is true if the pair was actually inserted.
825 *
826 * This function attempts to insert a (key, value) %pair into the %map.
827 * A %map relies on unique keys and thus a %pair is only inserted if its
828 * first element (the key) is not already present in the %map.
829 *
830 * Insertion requires logarithmic time.
831 * @{
832 */
833 std::pair<iterator, bool>
834 insert(const value_type& __x)
835 { return _M_t._M_insert_unique(__x); }
836
837#if __cplusplus >= 201103L
838 // _GLIBCXX_RESOLVE_LIB_DEFECTS
839 // 2354. Unnecessary copying when inserting into maps with braced-init
840 std::pair<iterator, bool>
841 insert(value_type&& __x)
842 { return _M_t._M_insert_unique(std::move(__x)); }
843
844 template<typename _Pair>
845 __enable_if_t<is_constructible<value_type, _Pair>::value,
846 pair<iterator, bool>>
847 insert(_Pair&& __x)
848 {
849#if __cplusplus >= 201703L
850 using _P2 = remove_reference_t<_Pair>;
851 if constexpr (__is_pair<remove_const_t<_P2>>)
852 if constexpr (is_same_v<allocator_type, allocator<value_type>>)
853 if constexpr (__usable_key<typename _P2::first_type>)
854 {
855 const key_type& __k = __x.first;
856 iterator __i = lower_bound(__k);
857 if (__i == end() || key_comp()(__k, (*__i).first))
858 {
859 __i = emplace_hint(__i, std::forward<_Pair>(__x));
860 return {__i, true};
861 }
862 return {__i, false};
863 }
864#endif
865 return _M_t._M_emplace_unique(std::forward<_Pair>(__x));
866 }
867#endif
868 /// @}
869
870#if __cplusplus >= 201103L
871 /**
872 * @brief Attempts to insert a list of std::pairs into the %map.
873 * @param __list A std::initializer_list<value_type> of pairs to be
874 * inserted.
875 *
876 * Complexity similar to that of the range constructor.
877 */
878 void
879 insert(std::initializer_list<value_type> __list)
880 { insert(__list.begin(), __list.end()); }
881#endif
882
883 /**
884 * @brief Attempts to insert a std::pair into the %map.
885 * @param __position An iterator that serves as a hint as to where the
886 * pair should be inserted.
887 * @param __x Pair to be inserted (see std::make_pair for easy creation
888 * of pairs).
889 * @return An iterator that points to the element with key of
890 * @a __x (may or may not be the %pair passed in).
891 *
892
893 * This function is not concerned about whether the insertion
894 * took place, and thus does not return a boolean like the
895 * single-argument insert() does. Note that the first
896 * parameter is only a hint and can potentially improve the
897 * performance of the insertion process. A bad hint would
898 * cause no gains in efficiency.
899 *
900 * See
901 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
902 * for more on @a hinting.
903 *
904 * Insertion requires logarithmic time (if the hint is not taken).
905 * @{
906 */
907 iterator
908#if __cplusplus >= 201103L
909 insert(const_iterator __position, const value_type& __x)
910#else
911 insert(iterator __position, const value_type& __x)
912#endif
913 { return _M_t._M_insert_unique_(__position, __x); }
914
915#if __cplusplus >= 201103L
916 // _GLIBCXX_RESOLVE_LIB_DEFECTS
917 // 2354. Unnecessary copying when inserting into maps with braced-init
918 iterator
919 insert(const_iterator __position, value_type&& __x)
920 { return _M_t._M_insert_unique_(__position, std::move(__x)); }
921
922 template<typename _Pair>
923 __enable_if_t<is_constructible<value_type, _Pair>::value, iterator>
924 insert(const_iterator __position, _Pair&& __x)
925 {
926 return _M_t._M_emplace_hint_unique(__position,
927 std::forward<_Pair>(__x));
928 }
929#endif
930 /// @}
931
932 /**
933 * @brief Template function that attempts to insert a range of elements.
934 * @param __first Iterator pointing to the start of the range to be
935 * inserted.
936 * @param __last Iterator pointing to the end of the range.
937 *
938 * Complexity similar to that of the range constructor.
939 */
940 template<typename _InputIterator>
941 void
942 insert(_InputIterator __first, _InputIterator __last)
943 { _M_t._M_insert_range_unique(__first, __last); }
944
945#if __cplusplus > 201402L
946 /**
947 * @brief Attempts to insert or assign a std::pair into the %map.
948 * @param __k Key to use for finding a possibly existing pair in
949 * the map.
950 * @param __obj Argument used to generate the .second for a pair
951 * instance.
952 *
953 * @return A pair, of which the first element is an iterator that
954 * points to the possibly inserted pair, and the second is
955 * a bool that is true if the pair was actually inserted.
956 *
957 * This function attempts to insert a (key, value) %pair into the %map.
958 * A %map relies on unique keys and thus a %pair is only inserted if its
959 * first element (the key) is not already present in the %map.
960 * If the %pair was already in the %map, the .second of the %pair
961 * is assigned from __obj.
962 *
963 * Insertion requires logarithmic time.
964 */
965 template <typename _Obj>
966 pair<iterator, bool>
967 insert_or_assign(const key_type& __k, _Obj&& __obj)
968 {
969 iterator __i = lower_bound(__k);
970 if (__i == end() || key_comp()(__k, (*__i).first))
971 {
972 __i = emplace_hint(__i, std::piecewise_construct,
973 std::forward_as_tuple(__k),
974 std::forward_as_tuple(
975 std::forward<_Obj>(__obj)));
976 return {__i, true};
977 }
978 (*__i).second = std::forward<_Obj>(__obj);
979 return {__i, false};
980 }
981
982 // move-capable overload
983 template <typename _Obj>
984 pair<iterator, bool>
985 insert_or_assign(key_type&& __k, _Obj&& __obj)
986 {
987 iterator __i = lower_bound(__k);
988 if (__i == end() || key_comp()(__k, (*__i).first))
989 {
990 __i = emplace_hint(__i, std::piecewise_construct,
991 std::forward_as_tuple(std::move(__k)),
992 std::forward_as_tuple(
993 std::forward<_Obj>(__obj)));
994 return {__i, true};
995 }
996 (*__i).second = std::forward<_Obj>(__obj);
997 return {__i, false};
998 }
999
1000 /**
1001 * @brief Attempts to insert or assign a std::pair into the %map.
1002 * @param __hint An iterator that serves as a hint as to where the
1003 * pair should be inserted.
1004 * @param __k Key to use for finding a possibly existing pair in
1005 * the map.
1006 * @param __obj Argument used to generate the .second for a pair
1007 * instance.
1008 *
1009 * @return An iterator that points to the element with key of
1010 * @a __x (may or may not be the %pair passed in).
1011 *
1012 * This function attempts to insert a (key, value) %pair into the %map.
1013 * A %map relies on unique keys and thus a %pair is only inserted if its
1014 * first element (the key) is not already present in the %map.
1015 * If the %pair was already in the %map, the .second of the %pair
1016 * is assigned from __obj.
1017 *
1018 * Insertion requires logarithmic time.
1019 */
1020 template <typename _Obj>
1021 iterator
1022 insert_or_assign(const_iterator __hint,
1023 const key_type& __k, _Obj&& __obj)
1024 {
1025 iterator __i;
1026 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
1027 if (__true_hint.second)
1028 {
1029 return emplace_hint(iterator(__true_hint.second),
1030 std::piecewise_construct,
1031 std::forward_as_tuple(__k),
1032 std::forward_as_tuple(
1033 std::forward<_Obj>(__obj)));
1034 }
1035 __i = iterator(__true_hint.first);
1036 (*__i).second = std::forward<_Obj>(__obj);
1037 return __i;
1038 }
1039
1040 // move-capable overload
1041 template <typename _Obj>
1042 iterator
1043 insert_or_assign(const_iterator __hint, key_type&& __k, _Obj&& __obj)
1044 {
1045 iterator __i;
1046 auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
1047 if (__true_hint.second)
1048 {
1049 return emplace_hint(iterator(__true_hint.second),
1050 std::piecewise_construct,
1051 std::forward_as_tuple(std::move(__k)),
1052 std::forward_as_tuple(
1053 std::forward<_Obj>(__obj)));
1054 }
1055 __i = iterator(__true_hint.first);
1056 (*__i).second = std::forward<_Obj>(__obj);
1057 return __i;
1058 }
1059#endif
1060
1061#if __cplusplus >= 201103L
1062 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1063 // DR 130. Associative erase should return an iterator.
1064 /**
1065 * @brief Erases an element from a %map.
1066 * @param __position An iterator pointing to the element to be erased.
1067 * @return An iterator pointing to the element immediately following
1068 * @a position prior to the element being erased. If no such
1069 * element exists, end() is returned.
1070 *
1071 * This function erases an element, pointed to by the given
1072 * iterator, from a %map. Note that this function only erases
1073 * the element, and that if the element is itself a pointer,
1074 * the pointed-to memory is not touched in any way. Managing
1075 * the pointer is the user's responsibility.
1076 *
1077 * @{
1078 */
1079 iterator
1080 erase(const_iterator __position)
1081 { return _M_t.erase(__position); }
1082
1083 // LWG 2059
1084 _GLIBCXX_ABI_TAG_CXX11
1085 iterator
1086 erase(iterator __position)
1087 { return _M_t.erase(__position); }
1088 /// @}
1089#else
1090 /**
1091 * @brief Erases an element from a %map.
1092 * @param __position An iterator pointing to the element to be erased.
1093 *
1094 * This function erases an element, pointed to by the given
1095 * iterator, from a %map. Note that this function only erases
1096 * the element, and that if the element is itself a pointer,
1097 * the pointed-to memory is not touched in any way. Managing
1098 * the pointer is the user's responsibility.
1099 */
1100 void
1101 erase(iterator __position)
1102 { _M_t.erase(__position); }
1103#endif
1104
1105 /**
1106 * @brief Erases elements according to the provided key.
1107 * @param __x Key of element to be erased.
1108 * @return The number of elements erased.
1109 *
1110 * This function erases all the elements located by the given key from
1111 * a %map.
1112 * Note that this function only erases the element, and that if
1113 * the element is itself a pointer, the pointed-to memory is not touched
1114 * in any way. Managing the pointer is the user's responsibility.
1115 */
1116 size_type
1117 erase(const key_type& __x)
1118 { return _M_t.erase(__x); }
1119
1120#if __cplusplus >= 201103L
1121 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1122 // DR 130. Associative erase should return an iterator.
1123 /**
1124 * @brief Erases a [first,last) range of elements from a %map.
1125 * @param __first Iterator pointing to the start of the range to be
1126 * erased.
1127 * @param __last Iterator pointing to the end of the range to
1128 * be erased.
1129 * @return The iterator @a __last.
1130 *
1131 * This function erases a sequence of elements from a %map.
1132 * Note that this function only erases the element, and that if
1133 * the element is itself a pointer, the pointed-to memory is not touched
1134 * in any way. Managing the pointer is the user's responsibility.
1135 */
1136 iterator
1137 erase(const_iterator __first, const_iterator __last)
1138 { return _M_t.erase(__first, __last); }
1139#else
1140 /**
1141 * @brief Erases a [__first,__last) range of elements from a %map.
1142 * @param __first Iterator pointing to the start of the range to be
1143 * erased.
1144 * @param __last Iterator pointing to the end of the range to
1145 * be erased.
1146 *
1147 * This function erases a sequence of elements from a %map.
1148 * Note that this function only erases the element, and that if
1149 * the element is itself a pointer, the pointed-to memory is not touched
1150 * in any way. Managing the pointer is the user's responsibility.
1151 */
1152 void
1153 erase(iterator __first, iterator __last)
1154 { _M_t.erase(__first, __last); }
1155#endif
1156
1157 /**
1158 * @brief Swaps data with another %map.
1159 * @param __x A %map of the same element and allocator types.
1160 *
1161 * This exchanges the elements between two maps in constant
1162 * time. (It is only swapping a pointer, an integer, and an
1163 * instance of the @c Compare type (which itself is often
1164 * stateless and empty), so it should be quite fast.) Note
1165 * that the global std::swap() function is specialized such
1166 * that std::swap(m1,m2) will feed to this function.
1167 *
1168 * Whether the allocators are swapped depends on the allocator traits.
1169 */
1170 void
1171 swap(map& __x)
1172 _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
1173 { _M_t.swap(__x._M_t); }
1174
1175 /**
1176 * Erases all elements in a %map. Note that this function only
1177 * erases the elements, and that if the elements themselves are
1178 * pointers, the pointed-to memory is not touched in any way.
1179 * Managing the pointer is the user's responsibility.
1180 */
1181 void
1182 clear() _GLIBCXX_NOEXCEPT
1183 { _M_t.clear(); }
1184
1185 // observers
1186 /**
1187 * Returns the key comparison object out of which the %map was
1188 * constructed.
1189 */
1190 key_compare
1191 key_comp() const
1192 { return _M_t.key_comp(); }
1193
1194 /**
1195 * Returns a value comparison object, built from the key comparison
1196 * object out of which the %map was constructed.
1197 */
1198 value_compare
1199 value_comp() const
1200 { return value_compare(_M_t.key_comp()); }
1201
1202 // [23.3.1.3] map operations
1203
1204 ///@{
1205 /**
1206 * @brief Tries to locate an element in a %map.
1207 * @param __x Key of (key, value) %pair to be located.
1208 * @return Iterator pointing to sought-after element, or end() if not
1209 * found.
1210 *
1211 * This function takes a key and tries to locate the element with which
1212 * the key matches. If successful the function returns an iterator
1213 * pointing to the sought after %pair. If unsuccessful it returns the
1214 * past-the-end ( @c end() ) iterator.
1215 */
1216
1217 iterator
1218 find(const key_type& __x)
1219 { return _M_t.find(__x); }
1220
1221#if __cplusplus > 201103L
1222 template<typename _Kt>
1223 auto
1224 find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
1225 { return _M_t._M_find_tr(__x); }
1226#endif
1227 ///@}
1228
1229 ///@{
1230 /**
1231 * @brief Tries to locate an element in a %map.
1232 * @param __x Key of (key, value) %pair to be located.
1233 * @return Read-only (constant) iterator pointing to sought-after
1234 * element, or end() if not found.
1235 *
1236 * This function takes a key and tries to locate the element with which
1237 * the key matches. If successful the function returns a constant
1238 * iterator pointing to the sought after %pair. If unsuccessful it
1239 * returns the past-the-end ( @c end() ) iterator.
1240 */
1241
1242 const_iterator
1243 find(const key_type& __x) const
1244 { return _M_t.find(__x); }
1245
1246#if __cplusplus > 201103L
1247 template<typename _Kt>
1248 auto
1249 find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
1250 { return _M_t._M_find_tr(__x); }
1251#endif
1252 ///@}
1253
1254 ///@{
1255 /**
1256 * @brief Finds the number of elements with given key.
1257 * @param __x Key of (key, value) pairs to be located.
1258 * @return Number of elements with specified key.
1259 *
1260 * This function only makes sense for multimaps; for map the result will
1261 * either be 0 (not present) or 1 (present).
1262 */
1263 size_type
1264 count(const key_type& __x) const
1265 { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
1266
1267#if __cplusplus > 201103L
1268 template<typename _Kt>
1269 auto
1270 count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
1271 { return _M_t._M_count_tr(__x); }
1272#endif
1273 ///@}
1274
1275#if __cplusplus > 201703L
1276 ///@{
1277 /**
1278 * @brief Finds whether an element with the given key exists.
1279 * @param __x Key of (key, value) pairs to be located.
1280 * @return True if there is an element with the specified key.
1281 */
1282 bool
1283 contains(const key_type& __x) const
1284 { return _M_t.find(__x) != _M_t.end(); }
1285
1286 template<typename _Kt>
1287 auto
1288 contains(const _Kt& __x) const
1289 -> decltype(_M_t._M_find_tr(__x), void(), true)
1290 { return _M_t._M_find_tr(__x) != _M_t.end(); }
1291 ///@}
1292#endif
1293
1294 ///@{
1295 /**
1296 * @brief Finds the beginning of a subsequence matching given key.
1297 * @param __x Key of (key, value) pair to be located.
1298 * @return Iterator pointing to first element equal to or greater
1299 * than key, or end().
1300 *
1301 * This function returns the first element of a subsequence of elements
1302 * that matches the given key. If unsuccessful it returns an iterator
1303 * pointing to the first element that has a greater value than given key
1304 * or end() if no such element exists.
1305 */
1306 iterator
1307 lower_bound(const key_type& __x)
1308 { return _M_t.lower_bound(__x); }
1309
1310#if __cplusplus > 201103L
1311 template<typename _Kt>
1312 auto
1313 lower_bound(const _Kt& __x)
1314 -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
1315 { return iterator(_M_t._M_lower_bound_tr(__x)); }
1316#endif
1317 ///@}
1318
1319 ///@{
1320 /**
1321 * @brief Finds the beginning of a subsequence matching given key.
1322 * @param __x Key of (key, value) pair to be located.
1323 * @return Read-only (constant) iterator pointing to first element
1324 * equal to or greater than key, or end().
1325 *
1326 * This function returns the first element of a subsequence of elements
1327 * that matches the given key. If unsuccessful it returns an iterator
1328 * pointing to the first element that has a greater value than given key
1329 * or end() if no such element exists.
1330 */
1331 const_iterator
1332 lower_bound(const key_type& __x) const
1333 { return _M_t.lower_bound(__x); }
1334
1335#if __cplusplus > 201103L
1336 template<typename _Kt>
1337 auto
1338 lower_bound(const _Kt& __x) const
1339 -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
1340 { return const_iterator(_M_t._M_lower_bound_tr(__x)); }
1341#endif
1342 ///@}
1343
1344 ///@{
1345 /**
1346 * @brief Finds the end of a subsequence matching given key.
1347 * @param __x Key of (key, value) pair to be located.
1348 * @return Iterator pointing to the first element
1349 * greater than key, or end().
1350 */
1351 iterator
1352 upper_bound(const key_type& __x)
1353 { return _M_t.upper_bound(__x); }
1354
1355#if __cplusplus > 201103L
1356 template<typename _Kt>
1357 auto
1358 upper_bound(const _Kt& __x)
1359 -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
1360 { return iterator(_M_t._M_upper_bound_tr(__x)); }
1361#endif
1362 ///@}
1363
1364 ///@{
1365 /**
1366 * @brief Finds the end of a subsequence matching given key.
1367 * @param __x Key of (key, value) pair to be located.
1368 * @return Read-only (constant) iterator pointing to first iterator
1369 * greater than key, or end().
1370 */
1371 const_iterator
1372 upper_bound(const key_type& __x) const
1373 { return _M_t.upper_bound(__x); }
1374
1375#if __cplusplus > 201103L
1376 template<typename _Kt>
1377 auto
1378 upper_bound(const _Kt& __x) const
1379 -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
1380 { return const_iterator(_M_t._M_upper_bound_tr(__x)); }
1381#endif
1382 ///@}
1383
1384 ///@{
1385 /**
1386 * @brief Finds a subsequence matching given key.
1387 * @param __x Key of (key, value) pairs to be located.
1388 * @return Pair of iterators that possibly points to the subsequence
1389 * matching given key.
1390 *
1391 * This function is equivalent to
1392 * @code
1393 * std::make_pair(c.lower_bound(val),
1394 * c.upper_bound(val))
1395 * @endcode
1396 * (but is faster than making the calls separately).
1397 *
1398 * This function probably only makes sense for multimaps.
1399 */
1400 std::pair<iterator, iterator>
1401 equal_range(const key_type& __x)
1402 { return _M_t.equal_range(__x); }
1403
1404#if __cplusplus > 201103L
1405 template<typename _Kt>
1406 auto
1407 equal_range(const _Kt& __x)
1408 -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
1409 { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
1410#endif
1411 ///@}
1412
1413 ///@{
1414 /**
1415 * @brief Finds a subsequence matching given key.
1416 * @param __x Key of (key, value) pairs to be located.
1417 * @return Pair of read-only (constant) iterators that possibly points
1418 * to the subsequence matching given key.
1419 *
1420 * This function is equivalent to
1421 * @code
1422 * std::make_pair(c.lower_bound(val),
1423 * c.upper_bound(val))
1424 * @endcode
1425 * (but is faster than making the calls separately).
1426 *
1427 * This function probably only makes sense for multimaps.
1428 */
1429 std::pair<const_iterator, const_iterator>
1430 equal_range(const key_type& __x) const
1431 { return _M_t.equal_range(__x); }
1432
1433#if __cplusplus > 201103L
1434 template<typename _Kt>
1435 auto
1436 equal_range(const _Kt& __x) const
1437 -> decltype(pair<const_iterator, const_iterator>(
1438 _M_t._M_equal_range_tr(__x)))
1439 {
1440 return pair<const_iterator, const_iterator>(
1441 _M_t._M_equal_range_tr(__x));
1442 }
1443#endif
1444 ///@}
1445
1446 template<typename _K1, typename _T1, typename _C1, typename _A1>
1447 friend bool
1448 operator==(const map<_K1, _T1, _C1, _A1>&,
1449 const map<_K1, _T1, _C1, _A1>&);
1450
1451#if __cpp_lib_three_way_comparison
1452 template<typename _K1, typename _T1, typename _C1, typename _A1>
1453 friend __detail::__synth3way_t<pair<const _K1, _T1>>
1454 operator<=>(const map<_K1, _T1, _C1, _A1>&,
1455 const map<_K1, _T1, _C1, _A1>&);
1456#else
1457 template<typename _K1, typename _T1, typename _C1, typename _A1>
1458 friend bool
1459 operator<(const map<_K1, _T1, _C1, _A1>&,
1460 const map<_K1, _T1, _C1, _A1>&);
1461#endif
1462 };
1463
1464
1465#if __cpp_deduction_guides >= 201606
1466
1467 template<typename _InputIterator,
1468 typename _Compare = less<__iter_key_t<_InputIterator>>,
1469 typename _Allocator = allocator<__iter_to_alloc_t<_InputIterator>>,
1470 typename = _RequireInputIter<_InputIterator>,
1471 typename = _RequireNotAllocator<_Compare>,
1472 typename = _RequireAllocator<_Allocator>>
1473 map(_InputIterator, _InputIterator,
1474 _Compare = _Compare(), _Allocator = _Allocator())
1475 -> map<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1476 _Compare, _Allocator>;
1477
1478 template<typename _Key, typename _Tp, typename _Compare = less<_Key>,
1479 typename _Allocator = allocator<pair<const _Key, _Tp>>,
1480 typename = _RequireNotAllocator<_Compare>,
1481 typename = _RequireAllocator<_Allocator>>
1482 map(initializer_list<pair<_Key, _Tp>>,
1483 _Compare = _Compare(), _Allocator = _Allocator())
1484 -> map<_Key, _Tp, _Compare, _Allocator>;
1485
1486 template <typename _InputIterator, typename _Allocator,
1487 typename = _RequireInputIter<_InputIterator>,
1488 typename = _RequireAllocator<_Allocator>>
1489 map(_InputIterator, _InputIterator, _Allocator)
1490 -> map<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1491 less<__iter_key_t<_InputIterator>>, _Allocator>;
1492
1493 template<typename _Key, typename _Tp, typename _Allocator,
1494 typename = _RequireAllocator<_Allocator>>
1495 map(initializer_list<pair<_Key, _Tp>>, _Allocator)
1496 -> map<_Key, _Tp, less<_Key>, _Allocator>;
1497
1498#endif // deduction guides
1499
1500 /**
1501 * @brief Map equality comparison.
1502 * @param __x A %map.
1503 * @param __y A %map of the same type as @a x.
1504 * @return True iff the size and elements of the maps are equal.
1505 *
1506 * This is an equivalence relation. It is linear in the size of the
1507 * maps. Maps are considered equivalent if their sizes are equal,
1508 * and if corresponding elements compare equal.
1509 */
1510 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1511 inline bool
1512 operator==(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1513 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1514 { return __x._M_t == __y._M_t; }
1515
1516#if __cpp_lib_three_way_comparison
1517 /**
1518 * @brief Map ordering relation.
1519 * @param __x A `map`.
1520 * @param __y A `map` of the same type as `x`.
1521 * @return A value indicating whether `__x` is less than, equal to,
1522 * greater than, or incomparable with `__y`.
1523 *
1524 * This is a total ordering relation. It is linear in the size of the
1525 * maps. The elements must be comparable with @c <.
1526 *
1527 * See `std::lexicographical_compare_three_way()` for how the determination
1528 * is made. This operator is used to synthesize relational operators like
1529 * `<` and `>=` etc.
1530 */
1531 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1532 inline __detail::__synth3way_t<pair<const _Key, _Tp>>
1533 operator<=>(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1534 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1535 { return __x._M_t <=> __y._M_t; }
1536#else
1537 /**
1538 * @brief Map ordering relation.
1539 * @param __x A %map.
1540 * @param __y A %map of the same type as @a x.
1541 * @return True iff @a x is lexicographically less than @a y.
1542 *
1543 * This is a total ordering relation. It is linear in the size of the
1544 * maps. The elements must be comparable with @c <.
1545 *
1546 * See std::lexicographical_compare() for how the determination is made.
1547 */
1548 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1549 inline bool
1550 operator<(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1551 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1552 { return __x._M_t < __y._M_t; }
1553
1554 /// Based on operator==
1555 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1556 inline bool
1557 operator!=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1558 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1559 { return !(__x == __y); }
1560
1561 /// Based on operator<
1562 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1563 inline bool
1564 operator>(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1565 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1566 { return __y < __x; }
1567
1568 /// Based on operator<
1569 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1570 inline bool
1571 operator<=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1572 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1573 { return !(__y < __x); }
1574
1575 /// Based on operator<
1576 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1577 inline bool
1578 operator>=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
1579 const map<_Key, _Tp, _Compare, _Alloc>& __y)
1580 { return !(__x < __y); }
1581#endif // three-way comparison
1582
1583 /// See std::map::swap().
1584 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1585 inline void
1586 swap(map<_Key, _Tp, _Compare, _Alloc>& __x,
1587 map<_Key, _Tp, _Compare, _Alloc>& __y)
1588 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
1589 { __x.swap(__y); }
1590
1591_GLIBCXX_END_NAMESPACE_CONTAINER
1592
1593#if __cplusplus > 201402L
1594 // Allow std::map access to internals of compatible maps.
1595 template<typename _Key, typename _Val, typename _Cmp1, typename _Alloc,
1596 typename _Cmp2>
1597 struct
1598 _Rb_tree_merge_helper<_GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>,
1599 _Cmp2>
1600 {
1601 private:
1602 friend class _GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>;
1603
1604 static auto&
1605 _S_get_tree(_GLIBCXX_STD_C::map<_Key, _Val, _Cmp2, _Alloc>& __map)
1606 { return __map._M_t; }
1607
1608 static auto&
1609 _S_get_tree(_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp2, _Alloc>& __map)
1610 { return __map._M_t; }
1611 };
1612#endif // C++17
1613
1614_GLIBCXX_END_NAMESPACE_VERSION
1615} // namespace std
1616
1617#endif /* _STL_MAP_H */
1618