1 | // unordered_map implementation -*- C++ -*- |
2 | |
3 | // Copyright (C) 2010-2024 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 | /** @file bits/unordered_map.h |
26 | * This is an internal header file, included by other library headers. |
27 | * Do not attempt to use it directly. @headername{unordered_map} |
28 | */ |
29 | |
30 | #ifndef _UNORDERED_MAP_H |
31 | #define _UNORDERED_MAP_H |
32 | |
33 | #include <bits/hashtable.h> |
34 | #include <bits/allocator.h> |
35 | #include <bits/functional_hash.h> // hash |
36 | #include <bits/stl_function.h> // equal_to |
37 | |
38 | namespace std _GLIBCXX_VISIBILITY(default) |
39 | { |
40 | _GLIBCXX_BEGIN_NAMESPACE_VERSION |
41 | _GLIBCXX_BEGIN_NAMESPACE_CONTAINER |
42 | |
43 | /// Base types for unordered_map. |
44 | template<bool _Cache> |
45 | using __umap_traits = __detail::_Hashtable_traits<_Cache, false, true>; |
46 | |
47 | template<typename _Key, |
48 | typename _Tp, |
49 | typename _Hash = hash<_Key>, |
50 | typename _Pred = std::equal_to<_Key>, |
51 | typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >, |
52 | typename _Tr = __umap_traits<__cache_default<_Key, _Hash>::value>> |
53 | using __umap_hashtable = _Hashtable<_Key, std::pair<const _Key, _Tp>, |
54 | _Alloc, __detail::_Select1st, |
55 | _Pred, _Hash, |
56 | __detail::_Mod_range_hashing, |
57 | __detail::_Default_ranged_hash, |
58 | __detail::_Prime_rehash_policy, _Tr>; |
59 | |
60 | /// Base types for unordered_multimap. |
61 | template<bool _Cache> |
62 | using __ummap_traits = __detail::_Hashtable_traits<_Cache, false, false>; |
63 | |
64 | template<typename _Key, |
65 | typename _Tp, |
66 | typename _Hash = hash<_Key>, |
67 | typename _Pred = std::equal_to<_Key>, |
68 | typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >, |
69 | typename _Tr = __ummap_traits<__cache_default<_Key, _Hash>::value>> |
70 | using __ummap_hashtable = _Hashtable<_Key, std::pair<const _Key, _Tp>, |
71 | _Alloc, __detail::_Select1st, |
72 | _Pred, _Hash, |
73 | __detail::_Mod_range_hashing, |
74 | __detail::_Default_ranged_hash, |
75 | __detail::_Prime_rehash_policy, _Tr>; |
76 | |
77 | template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc> |
78 | class unordered_multimap; |
79 | |
80 | /** |
81 | * @brief A standard container composed of unique keys (containing |
82 | * at most one of each key value) that associates values of another type |
83 | * with the keys. |
84 | * |
85 | * @ingroup unordered_associative_containers |
86 | * @headerfile unordered_map |
87 | * @since C++11 |
88 | * |
89 | * @tparam _Key Type of key objects. |
90 | * @tparam _Tp Type of mapped objects. |
91 | * @tparam _Hash Hashing function object type, defaults to hash<_Value>. |
92 | * @tparam _Pred Predicate function object type, defaults |
93 | * to equal_to<_Value>. |
94 | * @tparam _Alloc Allocator type, defaults to |
95 | * std::allocator<std::pair<const _Key, _Tp>>. |
96 | * |
97 | * Meets the requirements of a <a href="tables.html#65">container</a>, and |
98 | * <a href="tables.html#xx">unordered associative container</a> |
99 | * |
100 | * The resulting value type of the container is std::pair<const _Key, _Tp>. |
101 | * |
102 | * Base is _Hashtable, dispatched at compile time via template |
103 | * alias __umap_hashtable. |
104 | */ |
105 | template<typename _Key, typename _Tp, |
106 | typename _Hash = hash<_Key>, |
107 | typename _Pred = equal_to<_Key>, |
108 | typename _Alloc = allocator<std::pair<const _Key, _Tp>>> |
109 | class unordered_map |
110 | { |
111 | typedef __umap_hashtable<_Key, _Tp, _Hash, _Pred, _Alloc> _Hashtable; |
112 | _Hashtable _M_h; |
113 | |
114 | public: |
115 | // typedefs: |
116 | ///@{ |
117 | /// Public typedefs. |
118 | typedef typename _Hashtable::key_type key_type; |
119 | typedef typename _Hashtable::value_type value_type; |
120 | typedef typename _Hashtable::mapped_type mapped_type; |
121 | typedef typename _Hashtable::hasher hasher; |
122 | typedef typename _Hashtable::key_equal key_equal; |
123 | typedef typename _Hashtable::allocator_type allocator_type; |
124 | ///@} |
125 | |
126 | ///@{ |
127 | /// Iterator-related typedefs. |
128 | typedef typename _Hashtable::pointer pointer; |
129 | typedef typename _Hashtable::const_pointer const_pointer; |
130 | typedef typename _Hashtable::reference reference; |
131 | typedef typename _Hashtable::const_reference const_reference; |
132 | typedef typename _Hashtable::iterator iterator; |
133 | typedef typename _Hashtable::const_iterator const_iterator; |
134 | typedef typename _Hashtable::local_iterator local_iterator; |
135 | typedef typename _Hashtable::const_local_iterator const_local_iterator; |
136 | typedef typename _Hashtable::size_type size_type; |
137 | typedef typename _Hashtable::difference_type difference_type; |
138 | ///@} |
139 | |
140 | #if __cplusplus > 201402L |
141 | using node_type = typename _Hashtable::node_type; |
142 | using insert_return_type = typename _Hashtable::insert_return_type; |
143 | #endif |
144 | |
145 | //construct/destroy/copy |
146 | |
147 | /// Default constructor. |
148 | unordered_map() = default; |
149 | |
150 | /** |
151 | * @brief Default constructor creates no elements. |
152 | * @param __n Minimal initial number of buckets. |
153 | * @param __hf A hash functor. |
154 | * @param __eql A key equality functor. |
155 | * @param __a An allocator object. |
156 | */ |
157 | explicit |
158 | unordered_map(size_type __n, |
159 | const hasher& __hf = hasher(), |
160 | const key_equal& __eql = key_equal(), |
161 | const allocator_type& __a = allocator_type()) |
162 | : _M_h(__n, __hf, __eql, __a) |
163 | { } |
164 | |
165 | /** |
166 | * @brief Builds an %unordered_map from a range. |
167 | * @param __first An input iterator. |
168 | * @param __last An input iterator. |
169 | * @param __n Minimal initial number of buckets. |
170 | * @param __hf A hash functor. |
171 | * @param __eql A key equality functor. |
172 | * @param __a An allocator object. |
173 | * |
174 | * Create an %unordered_map consisting of copies of the elements from |
175 | * [__first,__last). This is linear in N (where N is |
176 | * distance(__first,__last)). |
177 | */ |
178 | template<typename _InputIterator> |
179 | unordered_map(_InputIterator __first, _InputIterator __last, |
180 | size_type __n = 0, |
181 | const hasher& __hf = hasher(), |
182 | const key_equal& __eql = key_equal(), |
183 | const allocator_type& __a = allocator_type()) |
184 | : _M_h(__first, __last, __n, __hf, __eql, __a) |
185 | { } |
186 | |
187 | /// Copy constructor. |
188 | unordered_map(const unordered_map&) = default; |
189 | |
190 | /// Move constructor. |
191 | unordered_map(unordered_map&&) = default; |
192 | |
193 | /** |
194 | * @brief Creates an %unordered_map with no elements. |
195 | * @param __a An allocator object. |
196 | */ |
197 | explicit |
198 | unordered_map(const allocator_type& __a) |
199 | : _M_h(__a) |
200 | { } |
201 | |
202 | /* |
203 | * @brief Copy constructor with allocator argument. |
204 | * @param __uset Input %unordered_map to copy. |
205 | * @param __a An allocator object. |
206 | */ |
207 | unordered_map(const unordered_map& __umap, |
208 | const allocator_type& __a) |
209 | : _M_h(__umap._M_h, __a) |
210 | { } |
211 | |
212 | /* |
213 | * @brief Move constructor with allocator argument. |
214 | * @param __uset Input %unordered_map to move. |
215 | * @param __a An allocator object. |
216 | */ |
217 | unordered_map(unordered_map&& __umap, |
218 | const allocator_type& __a) |
219 | noexcept( noexcept(_Hashtable(std::move(__umap._M_h), __a)) ) |
220 | : _M_h(std::move(__umap._M_h), __a) |
221 | { } |
222 | |
223 | /** |
224 | * @brief Builds an %unordered_map from an initializer_list. |
225 | * @param __l An initializer_list. |
226 | * @param __n Minimal initial number of buckets. |
227 | * @param __hf A hash functor. |
228 | * @param __eql A key equality functor. |
229 | * @param __a An allocator object. |
230 | * |
231 | * Create an %unordered_map consisting of copies of the elements in the |
232 | * list. This is linear in N (where N is @a __l.size()). |
233 | */ |
234 | unordered_map(initializer_list<value_type> __l, |
235 | size_type __n = 0, |
236 | const hasher& __hf = hasher(), |
237 | const key_equal& __eql = key_equal(), |
238 | const allocator_type& __a = allocator_type()) |
239 | : _M_h(__l, __n, __hf, __eql, __a) |
240 | { } |
241 | |
242 | unordered_map(size_type __n, const allocator_type& __a) |
243 | : unordered_map(__n, hasher(), key_equal(), __a) |
244 | { } |
245 | |
246 | unordered_map(size_type __n, const hasher& __hf, |
247 | const allocator_type& __a) |
248 | : unordered_map(__n, __hf, key_equal(), __a) |
249 | { } |
250 | |
251 | template<typename _InputIterator> |
252 | unordered_map(_InputIterator __first, _InputIterator __last, |
253 | size_type __n, |
254 | const allocator_type& __a) |
255 | : unordered_map(__first, __last, __n, hasher(), key_equal(), __a) |
256 | { } |
257 | |
258 | template<typename _InputIterator> |
259 | unordered_map(_InputIterator __first, _InputIterator __last, |
260 | size_type __n, const hasher& __hf, |
261 | const allocator_type& __a) |
262 | : unordered_map(__first, __last, __n, __hf, key_equal(), __a) |
263 | { } |
264 | |
265 | unordered_map(initializer_list<value_type> __l, |
266 | size_type __n, |
267 | const allocator_type& __a) |
268 | : unordered_map(__l, __n, hasher(), key_equal(), __a) |
269 | { } |
270 | |
271 | unordered_map(initializer_list<value_type> __l, |
272 | size_type __n, const hasher& __hf, |
273 | const allocator_type& __a) |
274 | : unordered_map(__l, __n, __hf, key_equal(), __a) |
275 | { } |
276 | |
277 | /// Copy assignment operator. |
278 | unordered_map& |
279 | operator=(const unordered_map&) = default; |
280 | |
281 | /// Move assignment operator. |
282 | unordered_map& |
283 | operator=(unordered_map&&) = default; |
284 | |
285 | /** |
286 | * @brief %Unordered_map list assignment operator. |
287 | * @param __l An initializer_list. |
288 | * |
289 | * This function fills an %unordered_map with copies of the elements in |
290 | * the initializer list @a __l. |
291 | * |
292 | * Note that the assignment completely changes the %unordered_map and |
293 | * that the resulting %unordered_map's size is the same as the number |
294 | * of elements assigned. |
295 | */ |
296 | unordered_map& |
297 | operator=(initializer_list<value_type> __l) |
298 | { |
299 | _M_h = __l; |
300 | return *this; |
301 | } |
302 | |
303 | /// Returns the allocator object used by the %unordered_map. |
304 | allocator_type |
305 | get_allocator() const noexcept |
306 | { return _M_h.get_allocator(); } |
307 | |
308 | // size and capacity: |
309 | |
310 | /// Returns true if the %unordered_map is empty. |
311 | _GLIBCXX_NODISCARD bool |
312 | empty() const noexcept |
313 | { return _M_h.empty(); } |
314 | |
315 | /// Returns the size of the %unordered_map. |
316 | size_type |
317 | size() const noexcept |
318 | { return _M_h.size(); } |
319 | |
320 | /// Returns the maximum size of the %unordered_map. |
321 | size_type |
322 | max_size() const noexcept |
323 | { return _M_h.max_size(); } |
324 | |
325 | // iterators. |
326 | |
327 | /** |
328 | * Returns a read/write iterator that points to the first element in the |
329 | * %unordered_map. |
330 | */ |
331 | iterator |
332 | begin() noexcept |
333 | { return _M_h.begin(); } |
334 | |
335 | ///@{ |
336 | /** |
337 | * Returns a read-only (constant) iterator that points to the first |
338 | * element in the %unordered_map. |
339 | */ |
340 | const_iterator |
341 | begin() const noexcept |
342 | { return _M_h.begin(); } |
343 | |
344 | const_iterator |
345 | cbegin() const noexcept |
346 | { return _M_h.begin(); } |
347 | ///@} |
348 | |
349 | /** |
350 | * Returns a read/write iterator that points one past the last element in |
351 | * the %unordered_map. |
352 | */ |
353 | iterator |
354 | end() noexcept |
355 | { return _M_h.end(); } |
356 | |
357 | ///@{ |
358 | /** |
359 | * Returns a read-only (constant) iterator that points one past the last |
360 | * element in the %unordered_map. |
361 | */ |
362 | const_iterator |
363 | end() const noexcept |
364 | { return _M_h.end(); } |
365 | |
366 | const_iterator |
367 | cend() const noexcept |
368 | { return _M_h.end(); } |
369 | ///@} |
370 | |
371 | // modifiers. |
372 | |
373 | /** |
374 | * @brief Attempts to build and insert a std::pair into the |
375 | * %unordered_map. |
376 | * |
377 | * @param __args Arguments used to generate a new pair instance (see |
378 | * std::piecewise_contruct for passing arguments to each |
379 | * part of the pair constructor). |
380 | * |
381 | * @return A pair, of which the first element is an iterator that points |
382 | * to the possibly inserted pair, and the second is a bool that |
383 | * is true if the pair was actually inserted. |
384 | * |
385 | * This function attempts to build and insert a (key, value) %pair into |
386 | * the %unordered_map. |
387 | * An %unordered_map relies on unique keys and thus a %pair is only |
388 | * inserted if its first element (the key) is not already present in the |
389 | * %unordered_map. |
390 | * |
391 | * Insertion requires amortized constant time. |
392 | */ |
393 | template<typename... _Args> |
394 | std::pair<iterator, bool> |
395 | emplace(_Args&&... __args) |
396 | { return _M_h.emplace(std::forward<_Args>(__args)...); } |
397 | |
398 | /** |
399 | * @brief Attempts to build and insert a std::pair into the |
400 | * %unordered_map. |
401 | * |
402 | * @param __pos An iterator that serves as a hint as to where the pair |
403 | * should be inserted. |
404 | * @param __args Arguments used to generate a new pair instance (see |
405 | * std::piecewise_contruct for passing arguments to each |
406 | * part of the pair constructor). |
407 | * @return An iterator that points to the element with key of the |
408 | * std::pair built from @a __args (may or may not be that |
409 | * std::pair). |
410 | * |
411 | * This function is not concerned about whether the insertion took place, |
412 | * and thus does not return a boolean like the single-argument emplace() |
413 | * does. |
414 | * Note that the first parameter is only a hint and can potentially |
415 | * improve the performance of the insertion process. A bad hint would |
416 | * cause no gains in efficiency. |
417 | * |
418 | * See |
419 | * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints |
420 | * for more on @a hinting. |
421 | * |
422 | * Insertion requires amortized constant time. |
423 | */ |
424 | template<typename... _Args> |
425 | iterator |
426 | emplace_hint(const_iterator __pos, _Args&&... __args) |
427 | { return _M_h.emplace_hint(__pos, std::forward<_Args>(__args)...); } |
428 | |
429 | #if __cplusplus > 201402L |
430 | /// Extract a node. |
431 | node_type |
432 | (const_iterator __pos) |
433 | { |
434 | __glibcxx_assert(__pos != end()); |
435 | return _M_h.extract(__pos); |
436 | } |
437 | |
438 | /// Extract a node. |
439 | node_type |
440 | (const key_type& __key) |
441 | { return _M_h.extract(__key); } |
442 | |
443 | /// Re-insert an extracted node. |
444 | insert_return_type |
445 | insert(node_type&& __nh) |
446 | { return _M_h._M_reinsert_node(std::move(__nh)); } |
447 | |
448 | /// Re-insert an extracted node. |
449 | iterator |
450 | insert(const_iterator, node_type&& __nh) |
451 | { return _M_h._M_reinsert_node(std::move(__nh)).position; } |
452 | #endif // C++17 |
453 | |
454 | #ifdef __glibcxx_unordered_map_try_emplace // C++ >= 17 && HOSTED |
455 | /** |
456 | * @brief Attempts to build and insert a std::pair into the |
457 | * %unordered_map. |
458 | * |
459 | * @param __k Key to use for finding a possibly existing pair in |
460 | * the unordered_map. |
461 | * @param __args Arguments used to generate the .second for a |
462 | * new pair instance. |
463 | * |
464 | * @return A pair, of which the first element is an iterator that points |
465 | * to the possibly inserted pair, and the second is a bool that |
466 | * is true if the pair was actually inserted. |
467 | * |
468 | * This function attempts to build and insert a (key, value) %pair into |
469 | * the %unordered_map. |
470 | * An %unordered_map relies on unique keys and thus a %pair is only |
471 | * inserted if its first element (the key) is not already present in the |
472 | * %unordered_map. |
473 | * If a %pair is not inserted, this function has no effect. |
474 | * |
475 | * Insertion requires amortized constant time. |
476 | */ |
477 | template <typename... _Args> |
478 | pair<iterator, bool> |
479 | try_emplace(const key_type& __k, _Args&&... __args) |
480 | { |
481 | return _M_h.try_emplace(cend(), __k, std::forward<_Args>(__args)...); |
482 | } |
483 | |
484 | // move-capable overload |
485 | template <typename... _Args> |
486 | pair<iterator, bool> |
487 | try_emplace(key_type&& __k, _Args&&... __args) |
488 | { |
489 | return _M_h.try_emplace(cend(), std::move(__k), |
490 | std::forward<_Args>(__args)...); |
491 | } |
492 | |
493 | /** |
494 | * @brief Attempts to build and insert a std::pair into the |
495 | * %unordered_map. |
496 | * |
497 | * @param __hint An iterator that serves as a hint as to where the pair |
498 | * should be inserted. |
499 | * @param __k Key to use for finding a possibly existing pair in |
500 | * the unordered_map. |
501 | * @param __args Arguments used to generate the .second for a |
502 | * new pair instance. |
503 | * @return An iterator that points to the element with key of the |
504 | * std::pair built from @a __args (may or may not be that |
505 | * std::pair). |
506 | * |
507 | * This function is not concerned about whether the insertion took place, |
508 | * and thus does not return a boolean like the single-argument emplace() |
509 | * does. However, if insertion did not take place, |
510 | * this function has no effect. |
511 | * Note that the first parameter is only a hint and can potentially |
512 | * improve the performance of the insertion process. A bad hint would |
513 | * cause no gains in efficiency. |
514 | * |
515 | * See |
516 | * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints |
517 | * for more on @a hinting. |
518 | * |
519 | * Insertion requires amortized constant time. |
520 | */ |
521 | template <typename... _Args> |
522 | iterator |
523 | try_emplace(const_iterator __hint, const key_type& __k, |
524 | _Args&&... __args) |
525 | { |
526 | return _M_h.try_emplace(__hint, __k, |
527 | std::forward<_Args>(__args)...).first; |
528 | } |
529 | |
530 | // move-capable overload |
531 | template <typename... _Args> |
532 | iterator |
533 | try_emplace(const_iterator __hint, key_type&& __k, _Args&&... __args) |
534 | { |
535 | return _M_h.try_emplace(__hint, std::move(__k), |
536 | std::forward<_Args>(__args)...).first; |
537 | } |
538 | #endif // __glibcxx_unordered_map_try_emplace |
539 | |
540 | ///@{ |
541 | /** |
542 | * @brief Attempts to insert a std::pair into the %unordered_map. |
543 | |
544 | * @param __x Pair to be inserted (see std::make_pair for easy |
545 | * creation of pairs). |
546 | * |
547 | * @return A pair, of which the first element is an iterator that |
548 | * points to the possibly inserted pair, and the second is |
549 | * a bool that is true if the pair was actually inserted. |
550 | * |
551 | * This function attempts to insert a (key, value) %pair into the |
552 | * %unordered_map. An %unordered_map relies on unique keys and thus a |
553 | * %pair is only inserted if its first element (the key) is not already |
554 | * present in the %unordered_map. |
555 | * |
556 | * Insertion requires amortized constant time. |
557 | */ |
558 | std::pair<iterator, bool> |
559 | insert(const value_type& __x) |
560 | { return _M_h.insert(__x); } |
561 | |
562 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
563 | // 2354. Unnecessary copying when inserting into maps with braced-init |
564 | std::pair<iterator, bool> |
565 | insert(value_type&& __x) |
566 | { return _M_h.insert(std::move(__x)); } |
567 | |
568 | template<typename _Pair> |
569 | __enable_if_t<is_constructible<value_type, _Pair&&>::value, |
570 | pair<iterator, bool>> |
571 | insert(_Pair&& __x) |
572 | { return _M_h.emplace(std::forward<_Pair>(__x)); } |
573 | ///@} |
574 | |
575 | ///@{ |
576 | /** |
577 | * @brief Attempts to insert a std::pair into the %unordered_map. |
578 | * @param __hint An iterator that serves as a hint as to where the |
579 | * pair should be inserted. |
580 | * @param __x Pair to be inserted (see std::make_pair for easy creation |
581 | * of pairs). |
582 | * @return An iterator that points to the element with key of |
583 | * @a __x (may or may not be the %pair passed in). |
584 | * |
585 | * This function is not concerned about whether the insertion took place, |
586 | * and thus does not return a boolean like the single-argument insert() |
587 | * does. Note that the first parameter is only a hint and can |
588 | * potentially improve the performance of the insertion process. A bad |
589 | * hint would cause no gains in efficiency. |
590 | * |
591 | * See |
592 | * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints |
593 | * for more on @a hinting. |
594 | * |
595 | * Insertion requires amortized constant time. |
596 | */ |
597 | iterator |
598 | insert(const_iterator __hint, const value_type& __x) |
599 | { return _M_h.insert(__hint, __x); } |
600 | |
601 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
602 | // 2354. Unnecessary copying when inserting into maps with braced-init |
603 | iterator |
604 | insert(const_iterator __hint, value_type&& __x) |
605 | { return _M_h.insert(__hint, std::move(__x)); } |
606 | |
607 | template<typename _Pair> |
608 | __enable_if_t<is_constructible<value_type, _Pair&&>::value, iterator> |
609 | insert(const_iterator __hint, _Pair&& __x) |
610 | { return _M_h.emplace_hint(__hint, std::forward<_Pair>(__x)); } |
611 | ///@} |
612 | |
613 | /** |
614 | * @brief A template function that attempts to insert a range of |
615 | * elements. |
616 | * @param __first Iterator pointing to the start of the range to be |
617 | * inserted. |
618 | * @param __last Iterator pointing to the end of the range. |
619 | * |
620 | * Complexity similar to that of the range constructor. |
621 | */ |
622 | template<typename _InputIterator> |
623 | void |
624 | insert(_InputIterator __first, _InputIterator __last) |
625 | { _M_h.insert(__first, __last); } |
626 | |
627 | /** |
628 | * @brief Attempts to insert a list of elements into the %unordered_map. |
629 | * @param __l A std::initializer_list<value_type> of elements |
630 | * to be inserted. |
631 | * |
632 | * Complexity similar to that of the range constructor. |
633 | */ |
634 | void |
635 | insert(initializer_list<value_type> __l) |
636 | { _M_h.insert(__l); } |
637 | |
638 | |
639 | #if __cplusplus > 201402L |
640 | /** |
641 | * @brief Attempts to insert a std::pair into the %unordered_map. |
642 | * @param __k Key to use for finding a possibly existing pair in |
643 | * the map. |
644 | * @param __obj Argument used to generate the .second for a pair |
645 | * instance. |
646 | * |
647 | * @return A pair, of which the first element is an iterator that |
648 | * points to the possibly inserted pair, and the second is |
649 | * a bool that is true if the pair was actually inserted. |
650 | * |
651 | * This function attempts to insert a (key, value) %pair into the |
652 | * %unordered_map. An %unordered_map relies on unique keys and thus a |
653 | * %pair is only inserted if its first element (the key) is not already |
654 | * present in the %unordered_map. |
655 | * If the %pair was already in the %unordered_map, the .second of |
656 | * the %pair is assigned from __obj. |
657 | * |
658 | * Insertion requires amortized constant time. |
659 | */ |
660 | template <typename _Obj> |
661 | pair<iterator, bool> |
662 | insert_or_assign(const key_type& __k, _Obj&& __obj) |
663 | { |
664 | auto __ret = _M_h.try_emplace(cend(), __k, |
665 | std::forward<_Obj>(__obj)); |
666 | if (!__ret.second) |
667 | __ret.first->second = std::forward<_Obj>(__obj); |
668 | return __ret; |
669 | } |
670 | |
671 | // move-capable overload |
672 | template <typename _Obj> |
673 | pair<iterator, bool> |
674 | insert_or_assign(key_type&& __k, _Obj&& __obj) |
675 | { |
676 | auto __ret = _M_h.try_emplace(cend(), std::move(__k), |
677 | std::forward<_Obj>(__obj)); |
678 | if (!__ret.second) |
679 | __ret.first->second = std::forward<_Obj>(__obj); |
680 | return __ret; |
681 | } |
682 | |
683 | /** |
684 | * @brief Attempts to insert a std::pair into the %unordered_map. |
685 | * @param __hint An iterator that serves as a hint as to where the |
686 | * pair should be inserted. |
687 | * @param __k Key to use for finding a possibly existing pair in |
688 | * the unordered_map. |
689 | * @param __obj Argument used to generate the .second for a pair |
690 | * instance. |
691 | * @return An iterator that points to the element with key of |
692 | * @a __x (may or may not be the %pair passed in). |
693 | * |
694 | * This function is not concerned about whether the insertion took place, |
695 | * and thus does not return a boolean like the single-argument insert() |
696 | * does. |
697 | * If the %pair was already in the %unordered map, the .second of |
698 | * the %pair is assigned from __obj. |
699 | * Note that the first parameter is only a hint and can |
700 | * potentially improve the performance of the insertion process. A bad |
701 | * hint would cause no gains in efficiency. |
702 | * |
703 | * See |
704 | * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints |
705 | * for more on @a hinting. |
706 | * |
707 | * Insertion requires amortized constant time. |
708 | */ |
709 | template <typename _Obj> |
710 | iterator |
711 | insert_or_assign(const_iterator __hint, const key_type& __k, |
712 | _Obj&& __obj) |
713 | { |
714 | auto __ret = _M_h.try_emplace(__hint, __k, std::forward<_Obj>(__obj)); |
715 | if (!__ret.second) |
716 | __ret.first->second = std::forward<_Obj>(__obj); |
717 | return __ret.first; |
718 | } |
719 | |
720 | // move-capable overload |
721 | template <typename _Obj> |
722 | iterator |
723 | insert_or_assign(const_iterator __hint, key_type&& __k, _Obj&& __obj) |
724 | { |
725 | auto __ret = _M_h.try_emplace(__hint, std::move(__k), |
726 | std::forward<_Obj>(__obj)); |
727 | if (!__ret.second) |
728 | __ret.first->second = std::forward<_Obj>(__obj); |
729 | return __ret.first; |
730 | } |
731 | #endif |
732 | |
733 | ///@{ |
734 | /** |
735 | * @brief Erases an element from an %unordered_map. |
736 | * @param __position An iterator pointing to the element to be erased. |
737 | * @return An iterator pointing to the element immediately following |
738 | * @a __position prior to the element being erased. If no such |
739 | * element exists, end() is returned. |
740 | * |
741 | * This function erases an element, pointed to by the given iterator, |
742 | * from an %unordered_map. |
743 | * Note that this function only erases the element, and that if the |
744 | * element is itself a pointer, the pointed-to memory is not touched in |
745 | * any way. Managing the pointer is the user's responsibility. |
746 | */ |
747 | iterator |
748 | erase(const_iterator __position) |
749 | { return _M_h.erase(__position); } |
750 | |
751 | // LWG 2059. |
752 | iterator |
753 | erase(iterator __position) |
754 | { return _M_h.erase(__position); } |
755 | ///@} |
756 | |
757 | /** |
758 | * @brief Erases elements according to the provided key. |
759 | * @param __x Key of element to be erased. |
760 | * @return The number of elements erased. |
761 | * |
762 | * This function erases all the elements located by the given key from |
763 | * an %unordered_map. For an %unordered_map the result of this function |
764 | * can only be 0 (not present) or 1 (present). |
765 | * Note that this function only erases the element, and that if the |
766 | * element is itself a pointer, the pointed-to memory is not touched in |
767 | * any way. Managing the pointer is the user's responsibility. |
768 | */ |
769 | size_type |
770 | erase(const key_type& __x) |
771 | { return _M_h.erase(__x); } |
772 | |
773 | /** |
774 | * @brief Erases a [__first,__last) range of elements from an |
775 | * %unordered_map. |
776 | * @param __first Iterator pointing to the start of the range to be |
777 | * erased. |
778 | * @param __last Iterator pointing to the end of the range to |
779 | * be erased. |
780 | * @return The iterator @a __last. |
781 | * |
782 | * This function erases a sequence of elements from an %unordered_map. |
783 | * Note that this function only erases the elements, and that if |
784 | * the element is itself a pointer, the pointed-to memory is not touched |
785 | * in any way. Managing the pointer is the user's responsibility. |
786 | */ |
787 | iterator |
788 | erase(const_iterator __first, const_iterator __last) |
789 | { return _M_h.erase(__first, __last); } |
790 | |
791 | /** |
792 | * Erases all elements in an %unordered_map. |
793 | * Note that this function only erases the elements, and that if the |
794 | * elements themselves are pointers, the pointed-to memory is not touched |
795 | * in any way. Managing the pointer is the user's responsibility. |
796 | */ |
797 | void |
798 | clear() noexcept |
799 | { _M_h.clear(); } |
800 | |
801 | /** |
802 | * @brief Swaps data with another %unordered_map. |
803 | * @param __x An %unordered_map of the same element and allocator |
804 | * types. |
805 | * |
806 | * This exchanges the elements between two %unordered_map in constant |
807 | * time. |
808 | * Note that the global std::swap() function is specialized such that |
809 | * std::swap(m1,m2) will feed to this function. |
810 | */ |
811 | void |
812 | swap(unordered_map& __x) |
813 | noexcept( noexcept(_M_h.swap(__x._M_h)) ) |
814 | { _M_h.swap(__x._M_h); } |
815 | |
816 | #if __cplusplus > 201402L |
817 | template<typename, typename, typename> |
818 | friend class std::_Hash_merge_helper; |
819 | |
820 | template<typename _H2, typename _P2> |
821 | void |
822 | merge(unordered_map<_Key, _Tp, _H2, _P2, _Alloc>& __source) |
823 | { |
824 | using _Merge_helper = _Hash_merge_helper<unordered_map, _H2, _P2>; |
825 | _M_h._M_merge_unique(_Merge_helper::_S_get_table(__source)); |
826 | } |
827 | |
828 | template<typename _H2, typename _P2> |
829 | void |
830 | merge(unordered_map<_Key, _Tp, _H2, _P2, _Alloc>&& __source) |
831 | { merge(__source); } |
832 | |
833 | template<typename _H2, typename _P2> |
834 | void |
835 | merge(unordered_multimap<_Key, _Tp, _H2, _P2, _Alloc>& __source) |
836 | { |
837 | using _Merge_helper = _Hash_merge_helper<unordered_map, _H2, _P2>; |
838 | _M_h._M_merge_unique(_Merge_helper::_S_get_table(__source)); |
839 | } |
840 | |
841 | template<typename _H2, typename _P2> |
842 | void |
843 | merge(unordered_multimap<_Key, _Tp, _H2, _P2, _Alloc>&& __source) |
844 | { merge(__source); } |
845 | #endif // C++17 |
846 | |
847 | // observers. |
848 | |
849 | /// Returns the hash functor object with which the %unordered_map was |
850 | /// constructed. |
851 | hasher |
852 | hash_function() const |
853 | { return _M_h.hash_function(); } |
854 | |
855 | /// Returns the key comparison object with which the %unordered_map was |
856 | /// constructed. |
857 | key_equal |
858 | key_eq() const |
859 | { return _M_h.key_eq(); } |
860 | |
861 | // lookup. |
862 | |
863 | ///@{ |
864 | /** |
865 | * @brief Tries to locate an element in an %unordered_map. |
866 | * @param __x Key to be located. |
867 | * @return Iterator pointing to sought-after element, or end() if not |
868 | * found. |
869 | * |
870 | * This function takes a key and tries to locate the element with which |
871 | * the key matches. If successful the function returns an iterator |
872 | * pointing to the sought after element. If unsuccessful it returns the |
873 | * past-the-end ( @c end() ) iterator. |
874 | */ |
875 | iterator |
876 | find(const key_type& __x) |
877 | { return _M_h.find(__x); } |
878 | |
879 | #if __cplusplus > 201703L |
880 | template<typename _Kt> |
881 | auto |
882 | find(const _Kt& __x) -> decltype(_M_h._M_find_tr(__x)) |
883 | { return _M_h._M_find_tr(__x); } |
884 | #endif |
885 | |
886 | const_iterator |
887 | find(const key_type& __x) const |
888 | { return _M_h.find(__x); } |
889 | |
890 | #if __cplusplus > 201703L |
891 | template<typename _Kt> |
892 | auto |
893 | find(const _Kt& __x) const -> decltype(_M_h._M_find_tr(__x)) |
894 | { return _M_h._M_find_tr(__x); } |
895 | #endif |
896 | ///@} |
897 | |
898 | ///@{ |
899 | /** |
900 | * @brief Finds the number of elements. |
901 | * @param __x Key to count. |
902 | * @return Number of elements with specified key. |
903 | * |
904 | * This function only makes sense for %unordered_multimap; for |
905 | * %unordered_map the result will either be 0 (not present) or 1 |
906 | * (present). |
907 | */ |
908 | size_type |
909 | count(const key_type& __x) const |
910 | { return _M_h.count(__x); } |
911 | |
912 | #if __cplusplus > 201703L |
913 | template<typename _Kt> |
914 | auto |
915 | count(const _Kt& __x) const -> decltype(_M_h._M_count_tr(__x)) |
916 | { return _M_h._M_count_tr(__x); } |
917 | #endif |
918 | ///@} |
919 | |
920 | #if __cplusplus > 201703L |
921 | ///@{ |
922 | /** |
923 | * @brief Finds whether an element with the given key exists. |
924 | * @param __x Key of elements to be located. |
925 | * @return True if there is any element with the specified key. |
926 | */ |
927 | bool |
928 | contains(const key_type& __x) const |
929 | { return _M_h.find(__x) != _M_h.end(); } |
930 | |
931 | template<typename _Kt> |
932 | auto |
933 | contains(const _Kt& __x) const |
934 | -> decltype(_M_h._M_find_tr(__x), void(), true) |
935 | { return _M_h._M_find_tr(__x) != _M_h.end(); } |
936 | ///@} |
937 | #endif |
938 | |
939 | ///@{ |
940 | /** |
941 | * @brief Finds a subsequence matching given key. |
942 | * @param __x Key to be located. |
943 | * @return Pair of iterators that possibly points to the subsequence |
944 | * matching given key. |
945 | * |
946 | * This function probably only makes sense for %unordered_multimap. |
947 | */ |
948 | std::pair<iterator, iterator> |
949 | equal_range(const key_type& __x) |
950 | { return _M_h.equal_range(__x); } |
951 | |
952 | #if __cplusplus > 201703L |
953 | template<typename _Kt> |
954 | auto |
955 | equal_range(const _Kt& __x) |
956 | -> decltype(_M_h._M_equal_range_tr(__x)) |
957 | { return _M_h._M_equal_range_tr(__x); } |
958 | #endif |
959 | |
960 | std::pair<const_iterator, const_iterator> |
961 | equal_range(const key_type& __x) const |
962 | { return _M_h.equal_range(__x); } |
963 | |
964 | #if __cplusplus > 201703L |
965 | template<typename _Kt> |
966 | auto |
967 | equal_range(const _Kt& __x) const |
968 | -> decltype(_M_h._M_equal_range_tr(__x)) |
969 | { return _M_h._M_equal_range_tr(__x); } |
970 | #endif |
971 | ///@} |
972 | |
973 | ///@{ |
974 | /** |
975 | * @brief Subscript ( @c [] ) access to %unordered_map data. |
976 | * @param __k The key for which data should be retrieved. |
977 | * @return A reference to the data of the (key,data) %pair. |
978 | * |
979 | * Allows for easy lookup with the subscript ( @c [] )operator. Returns |
980 | * data associated with the key specified in subscript. If the key does |
981 | * not exist, a pair with that key is created using default values, which |
982 | * is then returned. |
983 | * |
984 | * Lookup requires constant time. |
985 | */ |
986 | mapped_type& |
987 | operator[](const key_type& __k) |
988 | { return _M_h[__k]; } |
989 | |
990 | mapped_type& |
991 | operator[](key_type&& __k) |
992 | { return _M_h[std::move(__k)]; } |
993 | ///@} |
994 | |
995 | ///@{ |
996 | /** |
997 | * @brief Access to %unordered_map data. |
998 | * @param __k The key for which data should be retrieved. |
999 | * @return A reference to the data whose key is equal to @a __k, if |
1000 | * such a data is present in the %unordered_map. |
1001 | * @throw std::out_of_range If no such data is present. |
1002 | */ |
1003 | mapped_type& |
1004 | at(const key_type& __k) |
1005 | { return _M_h.at(__k); } |
1006 | |
1007 | const mapped_type& |
1008 | at(const key_type& __k) const |
1009 | { return _M_h.at(__k); } |
1010 | ///@} |
1011 | |
1012 | // bucket interface. |
1013 | |
1014 | /// Returns the number of buckets of the %unordered_map. |
1015 | size_type |
1016 | bucket_count() const noexcept |
1017 | { return _M_h.bucket_count(); } |
1018 | |
1019 | /// Returns the maximum number of buckets of the %unordered_map. |
1020 | size_type |
1021 | max_bucket_count() const noexcept |
1022 | { return _M_h.max_bucket_count(); } |
1023 | |
1024 | /* |
1025 | * @brief Returns the number of elements in a given bucket. |
1026 | * @param __n A bucket index. |
1027 | * @return The number of elements in the bucket. |
1028 | */ |
1029 | size_type |
1030 | bucket_size(size_type __n) const |
1031 | { return _M_h.bucket_size(__n); } |
1032 | |
1033 | /* |
1034 | * @brief Returns the bucket index of a given element. |
1035 | * @param __key A key instance. |
1036 | * @return The key bucket index. |
1037 | */ |
1038 | size_type |
1039 | bucket(const key_type& __key) const |
1040 | { return _M_h.bucket(__key); } |
1041 | |
1042 | /** |
1043 | * @brief Returns a read/write iterator pointing to the first bucket |
1044 | * element. |
1045 | * @param __n The bucket index. |
1046 | * @return A read/write local iterator. |
1047 | */ |
1048 | local_iterator |
1049 | begin(size_type __n) |
1050 | { return _M_h.begin(__n); } |
1051 | |
1052 | ///@{ |
1053 | /** |
1054 | * @brief Returns a read-only (constant) iterator pointing to the first |
1055 | * bucket element. |
1056 | * @param __n The bucket index. |
1057 | * @return A read-only local iterator. |
1058 | */ |
1059 | const_local_iterator |
1060 | begin(size_type __n) const |
1061 | { return _M_h.begin(__n); } |
1062 | |
1063 | const_local_iterator |
1064 | cbegin(size_type __n) const |
1065 | { return _M_h.cbegin(__n); } |
1066 | ///@} |
1067 | |
1068 | /** |
1069 | * @brief Returns a read/write iterator pointing to one past the last |
1070 | * bucket elements. |
1071 | * @param __n The bucket index. |
1072 | * @return A read/write local iterator. |
1073 | */ |
1074 | local_iterator |
1075 | end(size_type __n) |
1076 | { return _M_h.end(__n); } |
1077 | |
1078 | ///@{ |
1079 | /** |
1080 | * @brief Returns a read-only (constant) iterator pointing to one past |
1081 | * the last bucket elements. |
1082 | * @param __n The bucket index. |
1083 | * @return A read-only local iterator. |
1084 | */ |
1085 | const_local_iterator |
1086 | end(size_type __n) const |
1087 | { return _M_h.end(__n); } |
1088 | |
1089 | const_local_iterator |
1090 | cend(size_type __n) const |
1091 | { return _M_h.cend(__n); } |
1092 | ///@} |
1093 | |
1094 | // hash policy. |
1095 | |
1096 | /// Returns the average number of elements per bucket. |
1097 | float |
1098 | load_factor() const noexcept |
1099 | { return _M_h.load_factor(); } |
1100 | |
1101 | /// Returns a positive number that the %unordered_map tries to keep the |
1102 | /// load factor less than or equal to. |
1103 | float |
1104 | max_load_factor() const noexcept |
1105 | { return _M_h.max_load_factor(); } |
1106 | |
1107 | /** |
1108 | * @brief Change the %unordered_map maximum load factor. |
1109 | * @param __z The new maximum load factor. |
1110 | */ |
1111 | void |
1112 | max_load_factor(float __z) |
1113 | { _M_h.max_load_factor(__z); } |
1114 | |
1115 | /** |
1116 | * @brief May rehash the %unordered_map. |
1117 | * @param __n The new number of buckets. |
1118 | * |
1119 | * Rehash will occur only if the new number of buckets respect the |
1120 | * %unordered_map maximum load factor. |
1121 | */ |
1122 | void |
1123 | rehash(size_type __n) |
1124 | { _M_h.rehash(__n); } |
1125 | |
1126 | /** |
1127 | * @brief Prepare the %unordered_map for a specified number of |
1128 | * elements. |
1129 | * @param __n Number of elements required. |
1130 | * |
1131 | * Same as rehash(ceil(n / max_load_factor())). |
1132 | */ |
1133 | void |
1134 | reserve(size_type __n) |
1135 | { _M_h.reserve(__n); } |
1136 | |
1137 | template<typename _Key1, typename _Tp1, typename _Hash1, typename _Pred1, |
1138 | typename _Alloc1> |
1139 | friend bool |
1140 | operator==(const unordered_map<_Key1, _Tp1, _Hash1, _Pred1, _Alloc1>&, |
1141 | const unordered_map<_Key1, _Tp1, _Hash1, _Pred1, _Alloc1>&); |
1142 | }; |
1143 | |
1144 | #if __cpp_deduction_guides >= 201606 |
1145 | |
1146 | template<typename _InputIterator, |
1147 | typename _Hash = hash<__iter_key_t<_InputIterator>>, |
1148 | typename _Pred = equal_to<__iter_key_t<_InputIterator>>, |
1149 | typename _Allocator = allocator<__iter_to_alloc_t<_InputIterator>>, |
1150 | typename = _RequireInputIter<_InputIterator>, |
1151 | typename = _RequireNotAllocatorOrIntegral<_Hash>, |
1152 | typename = _RequireNotAllocator<_Pred>, |
1153 | typename = _RequireAllocator<_Allocator>> |
1154 | unordered_map(_InputIterator, _InputIterator, |
1155 | typename unordered_map<int, int>::size_type = {}, |
1156 | _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator()) |
1157 | -> unordered_map<__iter_key_t<_InputIterator>, |
1158 | __iter_val_t<_InputIterator>, |
1159 | _Hash, _Pred, _Allocator>; |
1160 | |
1161 | template<typename _Key, typename _Tp, typename _Hash = hash<_Key>, |
1162 | typename _Pred = equal_to<_Key>, |
1163 | typename _Allocator = allocator<pair<const _Key, _Tp>>, |
1164 | typename = _RequireNotAllocatorOrIntegral<_Hash>, |
1165 | typename = _RequireNotAllocator<_Pred>, |
1166 | typename = _RequireAllocator<_Allocator>> |
1167 | unordered_map(initializer_list<pair<_Key, _Tp>>, |
1168 | typename unordered_map<int, int>::size_type = {}, |
1169 | _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator()) |
1170 | -> unordered_map<_Key, _Tp, _Hash, _Pred, _Allocator>; |
1171 | |
1172 | template<typename _InputIterator, typename _Allocator, |
1173 | typename = _RequireInputIter<_InputIterator>, |
1174 | typename = _RequireAllocator<_Allocator>> |
1175 | unordered_map(_InputIterator, _InputIterator, |
1176 | typename unordered_map<int, int>::size_type, _Allocator) |
1177 | -> unordered_map<__iter_key_t<_InputIterator>, |
1178 | __iter_val_t<_InputIterator>, |
1179 | hash<__iter_key_t<_InputIterator>>, |
1180 | equal_to<__iter_key_t<_InputIterator>>, |
1181 | _Allocator>; |
1182 | |
1183 | template<typename _InputIterator, typename _Allocator, |
1184 | typename = _RequireInputIter<_InputIterator>, |
1185 | typename = _RequireAllocator<_Allocator>> |
1186 | unordered_map(_InputIterator, _InputIterator, _Allocator) |
1187 | -> unordered_map<__iter_key_t<_InputIterator>, |
1188 | __iter_val_t<_InputIterator>, |
1189 | hash<__iter_key_t<_InputIterator>>, |
1190 | equal_to<__iter_key_t<_InputIterator>>, |
1191 | _Allocator>; |
1192 | |
1193 | template<typename _InputIterator, typename _Hash, typename _Allocator, |
1194 | typename = _RequireInputIter<_InputIterator>, |
1195 | typename = _RequireNotAllocatorOrIntegral<_Hash>, |
1196 | typename = _RequireAllocator<_Allocator>> |
1197 | unordered_map(_InputIterator, _InputIterator, |
1198 | typename unordered_map<int, int>::size_type, |
1199 | _Hash, _Allocator) |
1200 | -> unordered_map<__iter_key_t<_InputIterator>, |
1201 | __iter_val_t<_InputIterator>, _Hash, |
1202 | equal_to<__iter_key_t<_InputIterator>>, _Allocator>; |
1203 | |
1204 | template<typename _Key, typename _Tp, typename _Allocator, |
1205 | typename = _RequireAllocator<_Allocator>> |
1206 | unordered_map(initializer_list<pair<_Key, _Tp>>, |
1207 | typename unordered_map<int, int>::size_type, |
1208 | _Allocator) |
1209 | -> unordered_map<_Key, _Tp, hash<_Key>, equal_to<_Key>, _Allocator>; |
1210 | |
1211 | template<typename _Key, typename _Tp, typename _Allocator, |
1212 | typename = _RequireAllocator<_Allocator>> |
1213 | unordered_map(initializer_list<pair<_Key, _Tp>>, _Allocator) |
1214 | -> unordered_map<_Key, _Tp, hash<_Key>, equal_to<_Key>, _Allocator>; |
1215 | |
1216 | template<typename _Key, typename _Tp, typename _Hash, typename _Allocator, |
1217 | typename = _RequireNotAllocatorOrIntegral<_Hash>, |
1218 | typename = _RequireAllocator<_Allocator>> |
1219 | unordered_map(initializer_list<pair<_Key, _Tp>>, |
1220 | typename unordered_map<int, int>::size_type, |
1221 | _Hash, _Allocator) |
1222 | -> unordered_map<_Key, _Tp, _Hash, equal_to<_Key>, _Allocator>; |
1223 | |
1224 | #endif |
1225 | |
1226 | /** |
1227 | * @brief A standard container composed of equivalent keys |
1228 | * (possibly containing multiple of each key value) that associates |
1229 | * values of another type with the keys. |
1230 | * |
1231 | * @ingroup unordered_associative_containers |
1232 | * @headerfile unordered_map |
1233 | * @since C++11 |
1234 | * |
1235 | * @tparam _Key Type of key objects. |
1236 | * @tparam _Tp Type of mapped objects. |
1237 | * @tparam _Hash Hashing function object type, defaults to hash<_Value>. |
1238 | * @tparam _Pred Predicate function object type, defaults |
1239 | * to equal_to<_Value>. |
1240 | * @tparam _Alloc Allocator type, defaults to |
1241 | * std::allocator<std::pair<const _Key, _Tp>>. |
1242 | * |
1243 | * Meets the requirements of a <a href="tables.html#65">container</a>, and |
1244 | * <a href="tables.html#xx">unordered associative container</a> |
1245 | * |
1246 | * The resulting value type of the container is std::pair<const _Key, _Tp>. |
1247 | * |
1248 | * Base is _Hashtable, dispatched at compile time via template |
1249 | * alias __ummap_hashtable. |
1250 | */ |
1251 | template<typename _Key, typename _Tp, |
1252 | typename _Hash = hash<_Key>, |
1253 | typename _Pred = equal_to<_Key>, |
1254 | typename _Alloc = allocator<std::pair<const _Key, _Tp>>> |
1255 | class unordered_multimap |
1256 | { |
1257 | typedef __ummap_hashtable<_Key, _Tp, _Hash, _Pred, _Alloc> _Hashtable; |
1258 | _Hashtable _M_h; |
1259 | |
1260 | public: |
1261 | // typedefs: |
1262 | ///@{ |
1263 | /// Public typedefs. |
1264 | typedef typename _Hashtable::key_type key_type; |
1265 | typedef typename _Hashtable::value_type value_type; |
1266 | typedef typename _Hashtable::mapped_type mapped_type; |
1267 | typedef typename _Hashtable::hasher hasher; |
1268 | typedef typename _Hashtable::key_equal key_equal; |
1269 | typedef typename _Hashtable::allocator_type allocator_type; |
1270 | ///@} |
1271 | |
1272 | ///@{ |
1273 | /// Iterator-related typedefs. |
1274 | typedef typename _Hashtable::pointer pointer; |
1275 | typedef typename _Hashtable::const_pointer const_pointer; |
1276 | typedef typename _Hashtable::reference reference; |
1277 | typedef typename _Hashtable::const_reference const_reference; |
1278 | typedef typename _Hashtable::iterator iterator; |
1279 | typedef typename _Hashtable::const_iterator const_iterator; |
1280 | typedef typename _Hashtable::local_iterator local_iterator; |
1281 | typedef typename _Hashtable::const_local_iterator const_local_iterator; |
1282 | typedef typename _Hashtable::size_type size_type; |
1283 | typedef typename _Hashtable::difference_type difference_type; |
1284 | ///@} |
1285 | |
1286 | #if __cplusplus > 201402L |
1287 | using node_type = typename _Hashtable::node_type; |
1288 | #endif |
1289 | |
1290 | //construct/destroy/copy |
1291 | |
1292 | /// Default constructor. |
1293 | unordered_multimap() = default; |
1294 | |
1295 | /** |
1296 | * @brief Default constructor creates no elements. |
1297 | * @param __n Mnimal initial number of buckets. |
1298 | * @param __hf A hash functor. |
1299 | * @param __eql A key equality functor. |
1300 | * @param __a An allocator object. |
1301 | */ |
1302 | explicit |
1303 | unordered_multimap(size_type __n, |
1304 | const hasher& __hf = hasher(), |
1305 | const key_equal& __eql = key_equal(), |
1306 | const allocator_type& __a = allocator_type()) |
1307 | : _M_h(__n, __hf, __eql, __a) |
1308 | { } |
1309 | |
1310 | /** |
1311 | * @brief Builds an %unordered_multimap from a range. |
1312 | * @param __first An input iterator. |
1313 | * @param __last An input iterator. |
1314 | * @param __n Minimal initial number of buckets. |
1315 | * @param __hf A hash functor. |
1316 | * @param __eql A key equality functor. |
1317 | * @param __a An allocator object. |
1318 | * |
1319 | * Create an %unordered_multimap consisting of copies of the elements |
1320 | * from [__first,__last). This is linear in N (where N is |
1321 | * distance(__first,__last)). |
1322 | */ |
1323 | template<typename _InputIterator> |
1324 | unordered_multimap(_InputIterator __first, _InputIterator __last, |
1325 | size_type __n = 0, |
1326 | const hasher& __hf = hasher(), |
1327 | const key_equal& __eql = key_equal(), |
1328 | const allocator_type& __a = allocator_type()) |
1329 | : _M_h(__first, __last, __n, __hf, __eql, __a) |
1330 | { } |
1331 | |
1332 | /// Copy constructor. |
1333 | unordered_multimap(const unordered_multimap&) = default; |
1334 | |
1335 | /// Move constructor. |
1336 | unordered_multimap(unordered_multimap&&) = default; |
1337 | |
1338 | /** |
1339 | * @brief Creates an %unordered_multimap with no elements. |
1340 | * @param __a An allocator object. |
1341 | */ |
1342 | explicit |
1343 | unordered_multimap(const allocator_type& __a) |
1344 | : _M_h(__a) |
1345 | { } |
1346 | |
1347 | /* |
1348 | * @brief Copy constructor with allocator argument. |
1349 | * @param __uset Input %unordered_multimap to copy. |
1350 | * @param __a An allocator object. |
1351 | */ |
1352 | unordered_multimap(const unordered_multimap& __ummap, |
1353 | const allocator_type& __a) |
1354 | : _M_h(__ummap._M_h, __a) |
1355 | { } |
1356 | |
1357 | /* |
1358 | * @brief Move constructor with allocator argument. |
1359 | * @param __uset Input %unordered_multimap to move. |
1360 | * @param __a An allocator object. |
1361 | */ |
1362 | unordered_multimap(unordered_multimap&& __ummap, |
1363 | const allocator_type& __a) |
1364 | noexcept( noexcept(_Hashtable(std::move(__ummap._M_h), __a)) ) |
1365 | : _M_h(std::move(__ummap._M_h), __a) |
1366 | { } |
1367 | |
1368 | /** |
1369 | * @brief Builds an %unordered_multimap from an initializer_list. |
1370 | * @param __l An initializer_list. |
1371 | * @param __n Minimal initial number of buckets. |
1372 | * @param __hf A hash functor. |
1373 | * @param __eql A key equality functor. |
1374 | * @param __a An allocator object. |
1375 | * |
1376 | * Create an %unordered_multimap consisting of copies of the elements in |
1377 | * the list. This is linear in N (where N is @a __l.size()). |
1378 | */ |
1379 | unordered_multimap(initializer_list<value_type> __l, |
1380 | size_type __n = 0, |
1381 | const hasher& __hf = hasher(), |
1382 | const key_equal& __eql = key_equal(), |
1383 | const allocator_type& __a = allocator_type()) |
1384 | : _M_h(__l, __n, __hf, __eql, __a) |
1385 | { } |
1386 | |
1387 | unordered_multimap(size_type __n, const allocator_type& __a) |
1388 | : unordered_multimap(__n, hasher(), key_equal(), __a) |
1389 | { } |
1390 | |
1391 | unordered_multimap(size_type __n, const hasher& __hf, |
1392 | const allocator_type& __a) |
1393 | : unordered_multimap(__n, __hf, key_equal(), __a) |
1394 | { } |
1395 | |
1396 | template<typename _InputIterator> |
1397 | unordered_multimap(_InputIterator __first, _InputIterator __last, |
1398 | size_type __n, |
1399 | const allocator_type& __a) |
1400 | : unordered_multimap(__first, __last, __n, hasher(), key_equal(), __a) |
1401 | { } |
1402 | |
1403 | template<typename _InputIterator> |
1404 | unordered_multimap(_InputIterator __first, _InputIterator __last, |
1405 | size_type __n, const hasher& __hf, |
1406 | const allocator_type& __a) |
1407 | : unordered_multimap(__first, __last, __n, __hf, key_equal(), __a) |
1408 | { } |
1409 | |
1410 | unordered_multimap(initializer_list<value_type> __l, |
1411 | size_type __n, |
1412 | const allocator_type& __a) |
1413 | : unordered_multimap(__l, __n, hasher(), key_equal(), __a) |
1414 | { } |
1415 | |
1416 | unordered_multimap(initializer_list<value_type> __l, |
1417 | size_type __n, const hasher& __hf, |
1418 | const allocator_type& __a) |
1419 | : unordered_multimap(__l, __n, __hf, key_equal(), __a) |
1420 | { } |
1421 | |
1422 | /// Copy assignment operator. |
1423 | unordered_multimap& |
1424 | operator=(const unordered_multimap&) = default; |
1425 | |
1426 | /// Move assignment operator. |
1427 | unordered_multimap& |
1428 | operator=(unordered_multimap&&) = default; |
1429 | |
1430 | /** |
1431 | * @brief %Unordered_multimap list assignment operator. |
1432 | * @param __l An initializer_list. |
1433 | * |
1434 | * This function fills an %unordered_multimap with copies of the |
1435 | * elements in the initializer list @a __l. |
1436 | * |
1437 | * Note that the assignment completely changes the %unordered_multimap |
1438 | * and that the resulting %unordered_multimap's size is the same as the |
1439 | * number of elements assigned. |
1440 | */ |
1441 | unordered_multimap& |
1442 | operator=(initializer_list<value_type> __l) |
1443 | { |
1444 | _M_h = __l; |
1445 | return *this; |
1446 | } |
1447 | |
1448 | /// Returns the allocator object used by the %unordered_multimap. |
1449 | allocator_type |
1450 | get_allocator() const noexcept |
1451 | { return _M_h.get_allocator(); } |
1452 | |
1453 | // size and capacity: |
1454 | |
1455 | /// Returns true if the %unordered_multimap is empty. |
1456 | _GLIBCXX_NODISCARD bool |
1457 | empty() const noexcept |
1458 | { return _M_h.empty(); } |
1459 | |
1460 | /// Returns the size of the %unordered_multimap. |
1461 | size_type |
1462 | size() const noexcept |
1463 | { return _M_h.size(); } |
1464 | |
1465 | /// Returns the maximum size of the %unordered_multimap. |
1466 | size_type |
1467 | max_size() const noexcept |
1468 | { return _M_h.max_size(); } |
1469 | |
1470 | // iterators. |
1471 | |
1472 | /** |
1473 | * Returns a read/write iterator that points to the first element in the |
1474 | * %unordered_multimap. |
1475 | */ |
1476 | iterator |
1477 | begin() noexcept |
1478 | { return _M_h.begin(); } |
1479 | |
1480 | ///@{ |
1481 | /** |
1482 | * Returns a read-only (constant) iterator that points to the first |
1483 | * element in the %unordered_multimap. |
1484 | */ |
1485 | const_iterator |
1486 | begin() const noexcept |
1487 | { return _M_h.begin(); } |
1488 | |
1489 | const_iterator |
1490 | cbegin() const noexcept |
1491 | { return _M_h.begin(); } |
1492 | ///@} |
1493 | |
1494 | /** |
1495 | * Returns a read/write iterator that points one past the last element in |
1496 | * the %unordered_multimap. |
1497 | */ |
1498 | iterator |
1499 | end() noexcept |
1500 | { return _M_h.end(); } |
1501 | |
1502 | ///@{ |
1503 | /** |
1504 | * Returns a read-only (constant) iterator that points one past the last |
1505 | * element in the %unordered_multimap. |
1506 | */ |
1507 | const_iterator |
1508 | end() const noexcept |
1509 | { return _M_h.end(); } |
1510 | |
1511 | const_iterator |
1512 | cend() const noexcept |
1513 | { return _M_h.end(); } |
1514 | ///@} |
1515 | |
1516 | // modifiers. |
1517 | |
1518 | /** |
1519 | * @brief Attempts to build and insert a std::pair into the |
1520 | * %unordered_multimap. |
1521 | * |
1522 | * @param __args Arguments used to generate a new pair instance (see |
1523 | * std::piecewise_contruct for passing arguments to each |
1524 | * part of the pair constructor). |
1525 | * |
1526 | * @return An iterator that points to the inserted pair. |
1527 | * |
1528 | * This function attempts to build and insert a (key, value) %pair into |
1529 | * the %unordered_multimap. |
1530 | * |
1531 | * Insertion requires amortized constant time. |
1532 | */ |
1533 | template<typename... _Args> |
1534 | iterator |
1535 | emplace(_Args&&... __args) |
1536 | { return _M_h.emplace(std::forward<_Args>(__args)...); } |
1537 | |
1538 | /** |
1539 | * @brief Attempts to build and insert a std::pair into the |
1540 | * %unordered_multimap. |
1541 | * |
1542 | * @param __pos An iterator that serves as a hint as to where the pair |
1543 | * should be inserted. |
1544 | * @param __args Arguments used to generate a new pair instance (see |
1545 | * std::piecewise_contruct for passing arguments to each |
1546 | * part of the pair constructor). |
1547 | * @return An iterator that points to the element with key of the |
1548 | * std::pair built from @a __args. |
1549 | * |
1550 | * Note that the first parameter is only a hint and can potentially |
1551 | * improve the performance of the insertion process. A bad hint would |
1552 | * cause no gains in efficiency. |
1553 | * |
1554 | * See |
1555 | * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints |
1556 | * for more on @a hinting. |
1557 | * |
1558 | * Insertion requires amortized constant time. |
1559 | */ |
1560 | template<typename... _Args> |
1561 | iterator |
1562 | emplace_hint(const_iterator __pos, _Args&&... __args) |
1563 | { return _M_h.emplace_hint(__pos, std::forward<_Args>(__args)...); } |
1564 | |
1565 | ///@{ |
1566 | /** |
1567 | * @brief Inserts a std::pair into the %unordered_multimap. |
1568 | * @param __x Pair to be inserted (see std::make_pair for easy |
1569 | * creation of pairs). |
1570 | * |
1571 | * @return An iterator that points to the inserted pair. |
1572 | * |
1573 | * Insertion requires amortized constant time. |
1574 | */ |
1575 | iterator |
1576 | insert(const value_type& __x) |
1577 | { return _M_h.insert(__x); } |
1578 | |
1579 | iterator |
1580 | insert(value_type&& __x) |
1581 | { return _M_h.insert(std::move(__x)); } |
1582 | |
1583 | template<typename _Pair> |
1584 | __enable_if_t<is_constructible<value_type, _Pair&&>::value, iterator> |
1585 | insert(_Pair&& __x) |
1586 | { return _M_h.emplace(std::forward<_Pair>(__x)); } |
1587 | ///@} |
1588 | |
1589 | ///@{ |
1590 | /** |
1591 | * @brief Inserts a std::pair into the %unordered_multimap. |
1592 | * @param __hint An iterator that serves as a hint as to where the |
1593 | * pair should be inserted. |
1594 | * @param __x Pair to be inserted (see std::make_pair for easy creation |
1595 | * of pairs). |
1596 | * @return An iterator that points to the element with key of |
1597 | * @a __x (may or may not be the %pair passed in). |
1598 | * |
1599 | * Note that the first parameter is only a hint and can potentially |
1600 | * improve the performance of the insertion process. A bad hint would |
1601 | * cause no gains in efficiency. |
1602 | * |
1603 | * See |
1604 | * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints |
1605 | * for more on @a hinting. |
1606 | * |
1607 | * Insertion requires amortized constant time. |
1608 | */ |
1609 | iterator |
1610 | insert(const_iterator __hint, const value_type& __x) |
1611 | { return _M_h.insert(__hint, __x); } |
1612 | |
1613 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
1614 | // 2354. Unnecessary copying when inserting into maps with braced-init |
1615 | iterator |
1616 | insert(const_iterator __hint, value_type&& __x) |
1617 | { return _M_h.insert(__hint, std::move(__x)); } |
1618 | |
1619 | template<typename _Pair> |
1620 | __enable_if_t<is_constructible<value_type, _Pair&&>::value, iterator> |
1621 | insert(const_iterator __hint, _Pair&& __x) |
1622 | { return _M_h.emplace_hint(__hint, std::forward<_Pair>(__x)); } |
1623 | ///@} |
1624 | |
1625 | /** |
1626 | * @brief A template function that attempts to insert a range of |
1627 | * elements. |
1628 | * @param __first Iterator pointing to the start of the range to be |
1629 | * inserted. |
1630 | * @param __last Iterator pointing to the end of the range. |
1631 | * |
1632 | * Complexity similar to that of the range constructor. |
1633 | */ |
1634 | template<typename _InputIterator> |
1635 | void |
1636 | insert(_InputIterator __first, _InputIterator __last) |
1637 | { _M_h.insert(__first, __last); } |
1638 | |
1639 | /** |
1640 | * @brief Attempts to insert a list of elements into the |
1641 | * %unordered_multimap. |
1642 | * @param __l A std::initializer_list<value_type> of elements |
1643 | * to be inserted. |
1644 | * |
1645 | * Complexity similar to that of the range constructor. |
1646 | */ |
1647 | void |
1648 | insert(initializer_list<value_type> __l) |
1649 | { _M_h.insert(__l); } |
1650 | |
1651 | #if __cplusplus > 201402L |
1652 | /// Extract a node. |
1653 | node_type |
1654 | (const_iterator __pos) |
1655 | { |
1656 | __glibcxx_assert(__pos != end()); |
1657 | return _M_h.extract(__pos); |
1658 | } |
1659 | |
1660 | /// Extract a node. |
1661 | node_type |
1662 | (const key_type& __key) |
1663 | { return _M_h.extract(__key); } |
1664 | |
1665 | /// Re-insert an extracted node. |
1666 | iterator |
1667 | insert(node_type&& __nh) |
1668 | { return _M_h._M_reinsert_node_multi(cend(), std::move(__nh)); } |
1669 | |
1670 | /// Re-insert an extracted node. |
1671 | iterator |
1672 | insert(const_iterator __hint, node_type&& __nh) |
1673 | { return _M_h._M_reinsert_node_multi(__hint, std::move(__nh)); } |
1674 | #endif // C++17 |
1675 | |
1676 | ///@{ |
1677 | /** |
1678 | * @brief Erases an element from an %unordered_multimap. |
1679 | * @param __position An iterator pointing to the element to be erased. |
1680 | * @return An iterator pointing to the element immediately following |
1681 | * @a __position prior to the element being erased. If no such |
1682 | * element exists, end() is returned. |
1683 | * |
1684 | * This function erases an element, pointed to by the given iterator, |
1685 | * from an %unordered_multimap. |
1686 | * Note that this function only erases the element, and that if the |
1687 | * element is itself a pointer, the pointed-to memory is not touched in |
1688 | * any way. Managing the pointer is the user's responsibility. |
1689 | */ |
1690 | iterator |
1691 | erase(const_iterator __position) |
1692 | { return _M_h.erase(__position); } |
1693 | |
1694 | // LWG 2059. |
1695 | iterator |
1696 | erase(iterator __position) |
1697 | { return _M_h.erase(__position); } |
1698 | ///@} |
1699 | |
1700 | /** |
1701 | * @brief Erases elements according to the provided key. |
1702 | * @param __x Key of elements to be erased. |
1703 | * @return The number of elements erased. |
1704 | * |
1705 | * This function erases all the elements located by the given key from |
1706 | * an %unordered_multimap. |
1707 | * Note that this function only erases the element, and that if the |
1708 | * element is itself a pointer, the pointed-to memory is not touched in |
1709 | * any way. Managing the pointer is the user's responsibility. |
1710 | */ |
1711 | size_type |
1712 | erase(const key_type& __x) |
1713 | { return _M_h.erase(__x); } |
1714 | |
1715 | /** |
1716 | * @brief Erases a [__first,__last) range of elements from an |
1717 | * %unordered_multimap. |
1718 | * @param __first Iterator pointing to the start of the range to be |
1719 | * erased. |
1720 | * @param __last Iterator pointing to the end of the range to |
1721 | * be erased. |
1722 | * @return The iterator @a __last. |
1723 | * |
1724 | * This function erases a sequence of elements from an |
1725 | * %unordered_multimap. |
1726 | * Note that this function only erases the elements, and that if |
1727 | * the element is itself a pointer, the pointed-to memory is not touched |
1728 | * in any way. Managing the pointer is the user's responsibility. |
1729 | */ |
1730 | iterator |
1731 | erase(const_iterator __first, const_iterator __last) |
1732 | { return _M_h.erase(__first, __last); } |
1733 | |
1734 | /** |
1735 | * Erases all elements in an %unordered_multimap. |
1736 | * Note that this function only erases the elements, and that if the |
1737 | * elements themselves are pointers, the pointed-to memory is not touched |
1738 | * in any way. Managing the pointer is the user's responsibility. |
1739 | */ |
1740 | void |
1741 | clear() noexcept |
1742 | { _M_h.clear(); } |
1743 | |
1744 | /** |
1745 | * @brief Swaps data with another %unordered_multimap. |
1746 | * @param __x An %unordered_multimap of the same element and allocator |
1747 | * types. |
1748 | * |
1749 | * This exchanges the elements between two %unordered_multimap in |
1750 | * constant time. |
1751 | * Note that the global std::swap() function is specialized such that |
1752 | * std::swap(m1,m2) will feed to this function. |
1753 | */ |
1754 | void |
1755 | swap(unordered_multimap& __x) |
1756 | noexcept( noexcept(_M_h.swap(__x._M_h)) ) |
1757 | { _M_h.swap(__x._M_h); } |
1758 | |
1759 | #if __cplusplus > 201402L |
1760 | template<typename, typename, typename> |
1761 | friend class std::_Hash_merge_helper; |
1762 | |
1763 | template<typename _H2, typename _P2> |
1764 | void |
1765 | merge(unordered_multimap<_Key, _Tp, _H2, _P2, _Alloc>& __source) |
1766 | { |
1767 | using _Merge_helper |
1768 | = _Hash_merge_helper<unordered_multimap, _H2, _P2>; |
1769 | _M_h._M_merge_multi(_Merge_helper::_S_get_table(__source)); |
1770 | } |
1771 | |
1772 | template<typename _H2, typename _P2> |
1773 | void |
1774 | merge(unordered_multimap<_Key, _Tp, _H2, _P2, _Alloc>&& __source) |
1775 | { merge(__source); } |
1776 | |
1777 | template<typename _H2, typename _P2> |
1778 | void |
1779 | merge(unordered_map<_Key, _Tp, _H2, _P2, _Alloc>& __source) |
1780 | { |
1781 | using _Merge_helper |
1782 | = _Hash_merge_helper<unordered_multimap, _H2, _P2>; |
1783 | _M_h._M_merge_multi(_Merge_helper::_S_get_table(__source)); |
1784 | } |
1785 | |
1786 | template<typename _H2, typename _P2> |
1787 | void |
1788 | merge(unordered_map<_Key, _Tp, _H2, _P2, _Alloc>&& __source) |
1789 | { merge(__source); } |
1790 | #endif // C++17 |
1791 | |
1792 | // observers. |
1793 | |
1794 | /// Returns the hash functor object with which the %unordered_multimap |
1795 | /// was constructed. |
1796 | hasher |
1797 | hash_function() const |
1798 | { return _M_h.hash_function(); } |
1799 | |
1800 | /// Returns the key comparison object with which the %unordered_multimap |
1801 | /// was constructed. |
1802 | key_equal |
1803 | key_eq() const |
1804 | { return _M_h.key_eq(); } |
1805 | |
1806 | // lookup. |
1807 | |
1808 | ///@{ |
1809 | /** |
1810 | * @brief Tries to locate an element in an %unordered_multimap. |
1811 | * @param __x Key to be located. |
1812 | * @return Iterator pointing to sought-after element, or end() if not |
1813 | * found. |
1814 | * |
1815 | * This function takes a key and tries to locate the element with which |
1816 | * the key matches. If successful the function returns an iterator |
1817 | * pointing to the sought after element. If unsuccessful it returns the |
1818 | * past-the-end ( @c end() ) iterator. |
1819 | */ |
1820 | iterator |
1821 | find(const key_type& __x) |
1822 | { return _M_h.find(__x); } |
1823 | |
1824 | #if __cplusplus > 201703L |
1825 | template<typename _Kt> |
1826 | auto |
1827 | find(const _Kt& __x) -> decltype(_M_h._M_find_tr(__x)) |
1828 | { return _M_h._M_find_tr(__x); } |
1829 | #endif |
1830 | |
1831 | const_iterator |
1832 | find(const key_type& __x) const |
1833 | { return _M_h.find(__x); } |
1834 | |
1835 | #if __cplusplus > 201703L |
1836 | template<typename _Kt> |
1837 | auto |
1838 | find(const _Kt& __x) const -> decltype(_M_h._M_find_tr(__x)) |
1839 | { return _M_h._M_find_tr(__x); } |
1840 | #endif |
1841 | ///@} |
1842 | |
1843 | ///@{ |
1844 | /** |
1845 | * @brief Finds the number of elements. |
1846 | * @param __x Key to count. |
1847 | * @return Number of elements with specified key. |
1848 | */ |
1849 | size_type |
1850 | count(const key_type& __x) const |
1851 | { return _M_h.count(__x); } |
1852 | |
1853 | #if __cplusplus > 201703L |
1854 | template<typename _Kt> |
1855 | auto |
1856 | count(const _Kt& __x) const -> decltype(_M_h._M_count_tr(__x)) |
1857 | { return _M_h._M_count_tr(__x); } |
1858 | #endif |
1859 | ///@} |
1860 | |
1861 | #if __cplusplus > 201703L |
1862 | ///@{ |
1863 | /** |
1864 | * @brief Finds whether an element with the given key exists. |
1865 | * @param __x Key of elements to be located. |
1866 | * @return True if there is any element with the specified key. |
1867 | */ |
1868 | bool |
1869 | contains(const key_type& __x) const |
1870 | { return _M_h.find(__x) != _M_h.end(); } |
1871 | |
1872 | template<typename _Kt> |
1873 | auto |
1874 | contains(const _Kt& __x) const |
1875 | -> decltype(_M_h._M_find_tr(__x), void(), true) |
1876 | { return _M_h._M_find_tr(__x) != _M_h.end(); } |
1877 | ///@} |
1878 | #endif |
1879 | |
1880 | ///@{ |
1881 | /** |
1882 | * @brief Finds a subsequence matching given key. |
1883 | * @param __x Key to be located. |
1884 | * @return Pair of iterators that possibly points to the subsequence |
1885 | * matching given key. |
1886 | */ |
1887 | std::pair<iterator, iterator> |
1888 | equal_range(const key_type& __x) |
1889 | { return _M_h.equal_range(__x); } |
1890 | |
1891 | #if __cplusplus > 201703L |
1892 | template<typename _Kt> |
1893 | auto |
1894 | equal_range(const _Kt& __x) |
1895 | -> decltype(_M_h._M_equal_range_tr(__x)) |
1896 | { return _M_h._M_equal_range_tr(__x); } |
1897 | #endif |
1898 | |
1899 | std::pair<const_iterator, const_iterator> |
1900 | equal_range(const key_type& __x) const |
1901 | { return _M_h.equal_range(__x); } |
1902 | |
1903 | #if __cplusplus > 201703L |
1904 | template<typename _Kt> |
1905 | auto |
1906 | equal_range(const _Kt& __x) const |
1907 | -> decltype(_M_h._M_equal_range_tr(__x)) |
1908 | { return _M_h._M_equal_range_tr(__x); } |
1909 | #endif |
1910 | ///@} |
1911 | |
1912 | // bucket interface. |
1913 | |
1914 | /// Returns the number of buckets of the %unordered_multimap. |
1915 | size_type |
1916 | bucket_count() const noexcept |
1917 | { return _M_h.bucket_count(); } |
1918 | |
1919 | /// Returns the maximum number of buckets of the %unordered_multimap. |
1920 | size_type |
1921 | max_bucket_count() const noexcept |
1922 | { return _M_h.max_bucket_count(); } |
1923 | |
1924 | /* |
1925 | * @brief Returns the number of elements in a given bucket. |
1926 | * @param __n A bucket index. |
1927 | * @return The number of elements in the bucket. |
1928 | */ |
1929 | size_type |
1930 | bucket_size(size_type __n) const |
1931 | { return _M_h.bucket_size(__n); } |
1932 | |
1933 | /* |
1934 | * @brief Returns the bucket index of a given element. |
1935 | * @param __key A key instance. |
1936 | * @return The key bucket index. |
1937 | */ |
1938 | size_type |
1939 | bucket(const key_type& __key) const |
1940 | { return _M_h.bucket(__key); } |
1941 | |
1942 | /** |
1943 | * @brief Returns a read/write iterator pointing to the first bucket |
1944 | * element. |
1945 | * @param __n The bucket index. |
1946 | * @return A read/write local iterator. |
1947 | */ |
1948 | local_iterator |
1949 | begin(size_type __n) |
1950 | { return _M_h.begin(__n); } |
1951 | |
1952 | ///@{ |
1953 | /** |
1954 | * @brief Returns a read-only (constant) iterator pointing to the first |
1955 | * bucket element. |
1956 | * @param __n The bucket index. |
1957 | * @return A read-only local iterator. |
1958 | */ |
1959 | const_local_iterator |
1960 | begin(size_type __n) const |
1961 | { return _M_h.begin(__n); } |
1962 | |
1963 | const_local_iterator |
1964 | cbegin(size_type __n) const |
1965 | { return _M_h.cbegin(__n); } |
1966 | ///@} |
1967 | |
1968 | /** |
1969 | * @brief Returns a read/write iterator pointing to one past the last |
1970 | * bucket elements. |
1971 | * @param __n The bucket index. |
1972 | * @return A read/write local iterator. |
1973 | */ |
1974 | local_iterator |
1975 | end(size_type __n) |
1976 | { return _M_h.end(__n); } |
1977 | |
1978 | ///@{ |
1979 | /** |
1980 | * @brief Returns a read-only (constant) iterator pointing to one past |
1981 | * the last bucket elements. |
1982 | * @param __n The bucket index. |
1983 | * @return A read-only local iterator. |
1984 | */ |
1985 | const_local_iterator |
1986 | end(size_type __n) const |
1987 | { return _M_h.end(__n); } |
1988 | |
1989 | const_local_iterator |
1990 | cend(size_type __n) const |
1991 | { return _M_h.cend(__n); } |
1992 | ///@} |
1993 | |
1994 | // hash policy. |
1995 | |
1996 | /// Returns the average number of elements per bucket. |
1997 | float |
1998 | load_factor() const noexcept |
1999 | { return _M_h.load_factor(); } |
2000 | |
2001 | /// Returns a positive number that the %unordered_multimap tries to keep |
2002 | /// the load factor less than or equal to. |
2003 | float |
2004 | max_load_factor() const noexcept |
2005 | { return _M_h.max_load_factor(); } |
2006 | |
2007 | /** |
2008 | * @brief Change the %unordered_multimap maximum load factor. |
2009 | * @param __z The new maximum load factor. |
2010 | */ |
2011 | void |
2012 | max_load_factor(float __z) |
2013 | { _M_h.max_load_factor(__z); } |
2014 | |
2015 | /** |
2016 | * @brief May rehash the %unordered_multimap. |
2017 | * @param __n The new number of buckets. |
2018 | * |
2019 | * Rehash will occur only if the new number of buckets respect the |
2020 | * %unordered_multimap maximum load factor. |
2021 | */ |
2022 | void |
2023 | rehash(size_type __n) |
2024 | { _M_h.rehash(__n); } |
2025 | |
2026 | /** |
2027 | * @brief Prepare the %unordered_multimap for a specified number of |
2028 | * elements. |
2029 | * @param __n Number of elements required. |
2030 | * |
2031 | * Same as rehash(ceil(n / max_load_factor())). |
2032 | */ |
2033 | void |
2034 | reserve(size_type __n) |
2035 | { _M_h.reserve(__n); } |
2036 | |
2037 | template<typename _Key1, typename _Tp1, typename _Hash1, typename _Pred1, |
2038 | typename _Alloc1> |
2039 | friend bool |
2040 | operator==(const unordered_multimap<_Key1, _Tp1, |
2041 | _Hash1, _Pred1, _Alloc1>&, |
2042 | const unordered_multimap<_Key1, _Tp1, |
2043 | _Hash1, _Pred1, _Alloc1>&); |
2044 | }; |
2045 | |
2046 | #if __cpp_deduction_guides >= 201606 |
2047 | |
2048 | template<typename _InputIterator, |
2049 | typename _Hash = hash<__iter_key_t<_InputIterator>>, |
2050 | typename _Pred = equal_to<__iter_key_t<_InputIterator>>, |
2051 | typename _Allocator = allocator<__iter_to_alloc_t<_InputIterator>>, |
2052 | typename = _RequireInputIter<_InputIterator>, |
2053 | typename = _RequireNotAllocatorOrIntegral<_Hash>, |
2054 | typename = _RequireNotAllocator<_Pred>, |
2055 | typename = _RequireAllocator<_Allocator>> |
2056 | unordered_multimap(_InputIterator, _InputIterator, |
2057 | unordered_multimap<int, int>::size_type = {}, |
2058 | _Hash = _Hash(), _Pred = _Pred(), |
2059 | _Allocator = _Allocator()) |
2060 | -> unordered_multimap<__iter_key_t<_InputIterator>, |
2061 | __iter_val_t<_InputIterator>, _Hash, _Pred, |
2062 | _Allocator>; |
2063 | |
2064 | template<typename _Key, typename _Tp, typename _Hash = hash<_Key>, |
2065 | typename _Pred = equal_to<_Key>, |
2066 | typename _Allocator = allocator<pair<const _Key, _Tp>>, |
2067 | typename = _RequireNotAllocatorOrIntegral<_Hash>, |
2068 | typename = _RequireNotAllocator<_Pred>, |
2069 | typename = _RequireAllocator<_Allocator>> |
2070 | unordered_multimap(initializer_list<pair<_Key, _Tp>>, |
2071 | unordered_multimap<int, int>::size_type = {}, |
2072 | _Hash = _Hash(), _Pred = _Pred(), |
2073 | _Allocator = _Allocator()) |
2074 | -> unordered_multimap<_Key, _Tp, _Hash, _Pred, _Allocator>; |
2075 | |
2076 | template<typename _InputIterator, typename _Allocator, |
2077 | typename = _RequireInputIter<_InputIterator>, |
2078 | typename = _RequireAllocator<_Allocator>> |
2079 | unordered_multimap(_InputIterator, _InputIterator, |
2080 | unordered_multimap<int, int>::size_type, _Allocator) |
2081 | -> unordered_multimap<__iter_key_t<_InputIterator>, |
2082 | __iter_val_t<_InputIterator>, |
2083 | hash<__iter_key_t<_InputIterator>>, |
2084 | equal_to<__iter_key_t<_InputIterator>>, _Allocator>; |
2085 | |
2086 | template<typename _InputIterator, typename _Allocator, |
2087 | typename = _RequireInputIter<_InputIterator>, |
2088 | typename = _RequireAllocator<_Allocator>> |
2089 | unordered_multimap(_InputIterator, _InputIterator, _Allocator) |
2090 | -> unordered_multimap<__iter_key_t<_InputIterator>, |
2091 | __iter_val_t<_InputIterator>, |
2092 | hash<__iter_key_t<_InputIterator>>, |
2093 | equal_to<__iter_key_t<_InputIterator>>, _Allocator>; |
2094 | |
2095 | template<typename _InputIterator, typename _Hash, typename _Allocator, |
2096 | typename = _RequireInputIter<_InputIterator>, |
2097 | typename = _RequireNotAllocatorOrIntegral<_Hash>, |
2098 | typename = _RequireAllocator<_Allocator>> |
2099 | unordered_multimap(_InputIterator, _InputIterator, |
2100 | unordered_multimap<int, int>::size_type, _Hash, |
2101 | _Allocator) |
2102 | -> unordered_multimap<__iter_key_t<_InputIterator>, |
2103 | __iter_val_t<_InputIterator>, _Hash, |
2104 | equal_to<__iter_key_t<_InputIterator>>, _Allocator>; |
2105 | |
2106 | template<typename _Key, typename _Tp, typename _Allocator, |
2107 | typename = _RequireAllocator<_Allocator>> |
2108 | unordered_multimap(initializer_list<pair<_Key, _Tp>>, |
2109 | unordered_multimap<int, int>::size_type, |
2110 | _Allocator) |
2111 | -> unordered_multimap<_Key, _Tp, hash<_Key>, equal_to<_Key>, _Allocator>; |
2112 | |
2113 | template<typename _Key, typename _Tp, typename _Allocator, |
2114 | typename = _RequireAllocator<_Allocator>> |
2115 | unordered_multimap(initializer_list<pair<_Key, _Tp>>, _Allocator) |
2116 | -> unordered_multimap<_Key, _Tp, hash<_Key>, equal_to<_Key>, _Allocator>; |
2117 | |
2118 | template<typename _Key, typename _Tp, typename _Hash, typename _Allocator, |
2119 | typename = _RequireNotAllocatorOrIntegral<_Hash>, |
2120 | typename = _RequireAllocator<_Allocator>> |
2121 | unordered_multimap(initializer_list<pair<_Key, _Tp>>, |
2122 | unordered_multimap<int, int>::size_type, |
2123 | _Hash, _Allocator) |
2124 | -> unordered_multimap<_Key, _Tp, _Hash, equal_to<_Key>, _Allocator>; |
2125 | |
2126 | #endif |
2127 | |
2128 | template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc> |
2129 | inline void |
2130 | swap(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, |
2131 | unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) |
2132 | noexcept(noexcept(__x.swap(__y))) |
2133 | { __x.swap(__y); } |
2134 | |
2135 | template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc> |
2136 | inline void |
2137 | swap(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, |
2138 | unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) |
2139 | noexcept(noexcept(__x.swap(__y))) |
2140 | { __x.swap(__y); } |
2141 | |
2142 | template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc> |
2143 | inline bool |
2144 | operator==(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, |
2145 | const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) |
2146 | { return __x._M_h._M_equal(__y._M_h); } |
2147 | |
2148 | #if __cpp_impl_three_way_comparison < 201907L |
2149 | template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc> |
2150 | inline bool |
2151 | operator!=(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, |
2152 | const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) |
2153 | { return !(__x == __y); } |
2154 | #endif |
2155 | |
2156 | template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc> |
2157 | inline bool |
2158 | operator==(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, |
2159 | const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) |
2160 | { return __x._M_h._M_equal(__y._M_h); } |
2161 | |
2162 | #if __cpp_impl_three_way_comparison < 201907L |
2163 | template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc> |
2164 | inline bool |
2165 | operator!=(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x, |
2166 | const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y) |
2167 | { return !(__x == __y); } |
2168 | #endif |
2169 | |
2170 | _GLIBCXX_END_NAMESPACE_CONTAINER |
2171 | |
2172 | #if __cplusplus > 201402L |
2173 | // Allow std::unordered_map access to internals of compatible maps. |
2174 | template<typename _Key, typename _Val, typename _Hash1, typename _Eq1, |
2175 | typename _Alloc, typename _Hash2, typename _Eq2> |
2176 | struct _Hash_merge_helper< |
2177 | _GLIBCXX_STD_C::unordered_map<_Key, _Val, _Hash1, _Eq1, _Alloc>, |
2178 | _Hash2, _Eq2> |
2179 | { |
2180 | private: |
2181 | template<typename... _Tp> |
2182 | using unordered_map = _GLIBCXX_STD_C::unordered_map<_Tp...>; |
2183 | template<typename... _Tp> |
2184 | using unordered_multimap = _GLIBCXX_STD_C::unordered_multimap<_Tp...>; |
2185 | |
2186 | friend unordered_map<_Key, _Val, _Hash1, _Eq1, _Alloc>; |
2187 | |
2188 | static auto& |
2189 | _S_get_table(unordered_map<_Key, _Val, _Hash2, _Eq2, _Alloc>& __map) |
2190 | { return __map._M_h; } |
2191 | |
2192 | static auto& |
2193 | _S_get_table(unordered_multimap<_Key, _Val, _Hash2, _Eq2, _Alloc>& __map) |
2194 | { return __map._M_h; } |
2195 | }; |
2196 | |
2197 | // Allow std::unordered_multimap access to internals of compatible maps. |
2198 | template<typename _Key, typename _Val, typename _Hash1, typename _Eq1, |
2199 | typename _Alloc, typename _Hash2, typename _Eq2> |
2200 | struct _Hash_merge_helper< |
2201 | _GLIBCXX_STD_C::unordered_multimap<_Key, _Val, _Hash1, _Eq1, _Alloc>, |
2202 | _Hash2, _Eq2> |
2203 | { |
2204 | private: |
2205 | template<typename... _Tp> |
2206 | using unordered_map = _GLIBCXX_STD_C::unordered_map<_Tp...>; |
2207 | template<typename... _Tp> |
2208 | using unordered_multimap = _GLIBCXX_STD_C::unordered_multimap<_Tp...>; |
2209 | |
2210 | friend unordered_multimap<_Key, _Val, _Hash1, _Eq1, _Alloc>; |
2211 | |
2212 | static auto& |
2213 | _S_get_table(unordered_map<_Key, _Val, _Hash2, _Eq2, _Alloc>& __map) |
2214 | { return __map._M_h; } |
2215 | |
2216 | static auto& |
2217 | _S_get_table(unordered_multimap<_Key, _Val, _Hash2, _Eq2, _Alloc>& __map) |
2218 | { return __map._M_h; } |
2219 | }; |
2220 | #endif // C++17 |
2221 | |
2222 | _GLIBCXX_END_NAMESPACE_VERSION |
2223 | } // namespace std |
2224 | |
2225 | #endif /* _UNORDERED_MAP_H */ |
2226 | |