xref: /freebsd/contrib/llvm-project/libcxx/include/unordered_map (revision 5f4c09dd85bff675e0ca63c55ea3c517e0fddfcc)
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_UNORDERED_MAP
11#define _LIBCPP_UNORDERED_MAP
12
13/*
14
15    unordered_map synopsis
16
17#include <initializer_list>
18
19namespace std
20{
21
22template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
23          class Alloc = allocator<pair<const Key, T>>>
24class unordered_map
25{
26public:
27    // types
28    typedef Key                                                        key_type;
29    typedef T                                                          mapped_type;
30    typedef Hash                                                       hasher;
31    typedef Pred                                                       key_equal;
32    typedef Alloc                                                      allocator_type;
33    typedef pair<const key_type, mapped_type>                          value_type;
34    typedef value_type&                                                reference;
35    typedef const value_type&                                          const_reference;
36    typedef typename allocator_traits<allocator_type>::pointer         pointer;
37    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
38    typedef typename allocator_traits<allocator_type>::size_type       size_type;
39    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
40
41    typedef /unspecified/ iterator;
42    typedef /unspecified/ const_iterator;
43    typedef /unspecified/ local_iterator;
44    typedef /unspecified/ const_local_iterator;
45
46    typedef unspecified                             node_type;            // C++17
47    typedef INSERT_RETURN_TYPE<iterator, node_type> insert_return_type;   // C++17
48
49    unordered_map()
50        noexcept(
51            is_nothrow_default_constructible<hasher>::value &&
52            is_nothrow_default_constructible<key_equal>::value &&
53            is_nothrow_default_constructible<allocator_type>::value);
54    explicit unordered_map(size_type n, const hasher& hf = hasher(),
55                           const key_equal& eql = key_equal(),
56                           const allocator_type& a = allocator_type());
57    template <class InputIterator>
58        unordered_map(InputIterator f, InputIterator l,
59                      size_type n = 0, const hasher& hf = hasher(),
60                      const key_equal& eql = key_equal(),
61                      const allocator_type& a = allocator_type());
62    explicit unordered_map(const allocator_type&);
63    unordered_map(const unordered_map&);
64    unordered_map(const unordered_map&, const Allocator&);
65    unordered_map(unordered_map&&)
66        noexcept(
67            is_nothrow_move_constructible<hasher>::value &&
68            is_nothrow_move_constructible<key_equal>::value &&
69            is_nothrow_move_constructible<allocator_type>::value);
70    unordered_map(unordered_map&&, const Allocator&);
71    unordered_map(initializer_list<value_type>, size_type n = 0,
72                  const hasher& hf = hasher(), const key_equal& eql = key_equal(),
73                  const allocator_type& a = allocator_type());
74    unordered_map(size_type n, const allocator_type& a)
75      : unordered_map(n, hasher(), key_equal(), a) {}  // C++14
76    unordered_map(size_type n, const hasher& hf, const allocator_type& a)
77      : unordered_map(n, hf, key_equal(), a) {}  // C++14
78    template <class InputIterator>
79      unordered_map(InputIterator f, InputIterator l, size_type n, const allocator_type& a)
80      : unordered_map(f, l, n, hasher(), key_equal(), a) {}  // C++14
81    template <class InputIterator>
82      unordered_map(InputIterator f, InputIterator l, size_type n, const hasher& hf,
83        const allocator_type& a)
84      : unordered_map(f, l, n, hf, key_equal(), a) {}  // C++14
85    unordered_map(initializer_list<value_type> il, size_type n, const allocator_type& a)
86      : unordered_map(il, n, hasher(), key_equal(), a) {}  // C++14
87    unordered_map(initializer_list<value_type> il, size_type n, const hasher& hf,
88      const allocator_type& a)
89      : unordered_map(il, n, hf, key_equal(), a) {}  // C++14
90    ~unordered_map();
91    unordered_map& operator=(const unordered_map&);
92    unordered_map& operator=(unordered_map&&)
93        noexcept(
94            allocator_type::propagate_on_container_move_assignment::value &&
95            is_nothrow_move_assignable<allocator_type>::value &&
96            is_nothrow_move_assignable<hasher>::value &&
97            is_nothrow_move_assignable<key_equal>::value);
98    unordered_map& operator=(initializer_list<value_type>);
99
100    allocator_type get_allocator() const noexcept;
101
102    bool      empty() const noexcept;
103    size_type size() const noexcept;
104    size_type max_size() const noexcept;
105
106    iterator       begin() noexcept;
107    iterator       end() noexcept;
108    const_iterator begin()  const noexcept;
109    const_iterator end()    const noexcept;
110    const_iterator cbegin() const noexcept;
111    const_iterator cend()   const noexcept;
112
113    template <class... Args>
114        pair<iterator, bool> emplace(Args&&... args);
115    template <class... Args>
116        iterator emplace_hint(const_iterator position, Args&&... args);
117    pair<iterator, bool> insert(const value_type& obj);
118    template <class P>
119        pair<iterator, bool> insert(P&& obj);
120    iterator insert(const_iterator hint, const value_type& obj);
121    template <class P>
122        iterator insert(const_iterator hint, P&& obj);
123    template <class InputIterator>
124        void insert(InputIterator first, InputIterator last);
125    void insert(initializer_list<value_type>);
126
127    node_type extract(const_iterator position);                                       // C++17
128    node_type extract(const key_type& x);                                             // C++17
129    insert_return_type insert(node_type&& nh);                                        // C++17
130    iterator           insert(const_iterator hint, node_type&& nh);                   // C++17
131
132    template <class... Args>
133        pair<iterator, bool> try_emplace(const key_type& k, Args&&... args);          // C++17
134    template <class... Args>
135        pair<iterator, bool> try_emplace(key_type&& k, Args&&... args);               // C++17
136    template <class... Args>
137        iterator try_emplace(const_iterator hint, const key_type& k, Args&&... args); // C++17
138    template <class... Args>
139        iterator try_emplace(const_iterator hint, key_type&& k, Args&&... args);      // C++17
140    template <class M>
141        pair<iterator, bool> insert_or_assign(const key_type& k, M&& obj);            // C++17
142    template <class M>
143        pair<iterator, bool> insert_or_assign(key_type&& k, M&& obj);                 // C++17
144    template <class M>
145        iterator insert_or_assign(const_iterator hint, const key_type& k, M&& obj);   // C++17
146    template <class M>
147        iterator insert_or_assign(const_iterator hint, key_type&& k, M&& obj);        // C++17
148
149    iterator erase(const_iterator position);
150    iterator erase(iterator position);  // C++14
151    size_type erase(const key_type& k);
152    iterator erase(const_iterator first, const_iterator last);
153    void clear() noexcept;
154
155    template<class H2, class P2>
156      void merge(unordered_map<Key, T, H2, P2, Allocator>& source);         // C++17
157    template<class H2, class P2>
158      void merge(unordered_map<Key, T, H2, P2, Allocator>&& source);        // C++17
159    template<class H2, class P2>
160      void merge(unordered_multimap<Key, T, H2, P2, Allocator>& source);    // C++17
161    template<class H2, class P2>
162      void merge(unordered_multimap<Key, T, H2, P2, Allocator>&& source);   // C++17
163
164    void swap(unordered_map&)
165        noexcept(
166            (!allocator_type::propagate_on_container_swap::value ||
167             __is_nothrow_swappable<allocator_type>::value) &&
168            __is_nothrow_swappable<hasher>::value &&
169            __is_nothrow_swappable<key_equal>::value);
170
171    hasher hash_function() const;
172    key_equal key_eq() const;
173
174    iterator       find(const key_type& k);
175    const_iterator find(const key_type& k) const;
176    template<typename K>
177        iterator find(const K& x);              // C++20
178    template<typename K>
179        const_iterator find(const K& x) const;  // C++20
180    size_type count(const key_type& k) const;
181    template<typename K>
182        size_type count(const K& k) const; // C++20
183    bool contains(const key_type& k) const; // C++20
184    template<typename K>
185        bool contains(const K& k) const; // C++20
186    pair<iterator, iterator>             equal_range(const key_type& k);
187    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
188    template<typename K>
189        pair<iterator, iterator>             equal_range(const K& k); // C++20
190    template<typename K>
191        pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
192
193    mapped_type& operator[](const key_type& k);
194    mapped_type& operator[](key_type&& k);
195
196    mapped_type&       at(const key_type& k);
197    const mapped_type& at(const key_type& k) const;
198
199    size_type bucket_count() const noexcept;
200    size_type max_bucket_count() const noexcept;
201
202    size_type bucket_size(size_type n) const;
203    size_type bucket(const key_type& k) const;
204
205    local_iterator       begin(size_type n);
206    local_iterator       end(size_type n);
207    const_local_iterator begin(size_type n) const;
208    const_local_iterator end(size_type n) const;
209    const_local_iterator cbegin(size_type n) const;
210    const_local_iterator cend(size_type n) const;
211
212    float load_factor() const noexcept;
213    float max_load_factor() const noexcept;
214    void max_load_factor(float z);
215    void rehash(size_type n);
216    void reserve(size_type n);
217};
218
219template<class InputIterator,
220    class Hash = hash<iter_key_t<InputIterator>>, class Pred = equal_to<iter_key_t<InputIterator>>,
221    class Allocator = allocator<iter_to_alloc_t<InputIterator>>>
222unordered_map(InputIterator, InputIterator, typename see below::size_type = see below,
223    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
224  -> unordered_map<iter_key_t<InputIterator>, iter_value_t<InputIterator>, Hash, Pred,
225    Allocator>; // C++17
226
227template<class Key, class T, class Hash = hash<Key>,
228    class Pred = equal_to<Key>, class Allocator = allocator<pair<const Key, T>>>
229unordered_map(initializer_list<pair<const Key, T>>, typename see below::size_type = see below,
230    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
231  -> unordered_map<Key, T, Hash, Pred, Allocator>; // C++17
232
233template<class InputIterator, class Allocator>
234unordered_map(InputIterator, InputIterator, typename see below::size_type, Allocator)
235  -> unordered_map<iter_key_t<InputIterator>, iter_val_t<InputIterator>,
236        hash<iter_key_t<InputIterator>>, equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
237
238template<class InputIterator, class Allocator>
239unordered_map(InputIterator, InputIterator, Allocator)
240  -> unordered_map<iter_key_t<InputIterator>, iter_val_t<InputIterator>,
241        hash<iter_key_t<InputIterator>>, equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
242
243template<class InputIterator, class Hash, class Allocator>
244unordered_map(InputIterator, InputIterator, typename see below::size_type, Hash, Allocator)
245  -> unordered_map<iter_key_t<InputIterator>, iter_val_t<InputIterator>, Hash,
246          equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
247
248template<class Key, class T, typename Allocator>
249unordered_map(initializer_list<pair<const Key, T>>, typename see below::size_type, Allocator)
250  -> unordered_map<Key, T, hash<Key>, equal_to<Key>, Allocator>; // C++17
251
252template<class Key, class T, typename Allocator>
253unordered_map(initializer_list<pair<const Key, T>>, Allocator)
254  -> unordered_map<Key, T, hash<Key>, equal_to<Key>, Allocator>; // C++17
255
256template<class Key, class T, class Hash, class Allocator>
257unordered_map(initializer_list<pair<const Key, T>>, typename see below::size_type, Hash, Allocator)
258  -> unordered_map<Key, T, Hash, equal_to<Key>, Allocator>; // C++17
259
260template <class Key, class T, class Hash, class Pred, class Alloc>
261    void swap(unordered_map<Key, T, Hash, Pred, Alloc>& x,
262              unordered_map<Key, T, Hash, Pred, Alloc>& y)
263              noexcept(noexcept(x.swap(y)));
264
265template <class Key, class T, class Hash, class Pred, class Alloc>
266    bool
267    operator==(const unordered_map<Key, T, Hash, Pred, Alloc>& x,
268               const unordered_map<Key, T, Hash, Pred, Alloc>& y);
269
270template <class Key, class T, class Hash, class Pred, class Alloc>
271    bool
272    operator!=(const unordered_map<Key, T, Hash, Pred, Alloc>& x,
273               const unordered_map<Key, T, Hash, Pred, Alloc>& y);
274
275template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
276          class Alloc = allocator<pair<const Key, T>>>
277class unordered_multimap
278{
279public:
280    // types
281    typedef Key                                                        key_type;
282    typedef T                                                          mapped_type;
283    typedef Hash                                                       hasher;
284    typedef Pred                                                       key_equal;
285    typedef Alloc                                                      allocator_type;
286    typedef pair<const key_type, mapped_type>                          value_type;
287    typedef value_type&                                                reference;
288    typedef const value_type&                                          const_reference;
289    typedef typename allocator_traits<allocator_type>::pointer         pointer;
290    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
291    typedef typename allocator_traits<allocator_type>::size_type       size_type;
292    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
293
294    typedef /unspecified/ iterator;
295    typedef /unspecified/ const_iterator;
296    typedef /unspecified/ local_iterator;
297    typedef /unspecified/ const_local_iterator;
298
299    typedef unspecified node_type;    // C++17
300
301    unordered_multimap()
302        noexcept(
303            is_nothrow_default_constructible<hasher>::value &&
304            is_nothrow_default_constructible<key_equal>::value &&
305            is_nothrow_default_constructible<allocator_type>::value);
306    explicit unordered_multimap(size_type n, const hasher& hf = hasher(),
307                           const key_equal& eql = key_equal(),
308                           const allocator_type& a = allocator_type());
309    template <class InputIterator>
310        unordered_multimap(InputIterator f, InputIterator l,
311                      size_type n = 0, const hasher& hf = hasher(),
312                      const key_equal& eql = key_equal(),
313                      const allocator_type& a = allocator_type());
314    explicit unordered_multimap(const allocator_type&);
315    unordered_multimap(const unordered_multimap&);
316    unordered_multimap(const unordered_multimap&, const Allocator&);
317    unordered_multimap(unordered_multimap&&)
318        noexcept(
319            is_nothrow_move_constructible<hasher>::value &&
320            is_nothrow_move_constructible<key_equal>::value &&
321            is_nothrow_move_constructible<allocator_type>::value);
322    unordered_multimap(unordered_multimap&&, const Allocator&);
323    unordered_multimap(initializer_list<value_type>, size_type n = 0,
324                  const hasher& hf = hasher(), const key_equal& eql = key_equal(),
325                  const allocator_type& a = allocator_type());
326    unordered_multimap(size_type n, const allocator_type& a)
327      : unordered_multimap(n, hasher(), key_equal(), a) {}  // C++14
328    unordered_multimap(size_type n, const hasher& hf, const allocator_type& a)
329      : unordered_multimap(n, hf, key_equal(), a) {}  // C++14
330    template <class InputIterator>
331      unordered_multimap(InputIterator f, InputIterator l, size_type n, const allocator_type& a)
332      : unordered_multimap(f, l, n, hasher(), key_equal(), a) {}  // C++14
333    template <class InputIterator>
334      unordered_multimap(InputIterator f, InputIterator l, size_type n, const hasher& hf,
335        const allocator_type& a)
336      : unordered_multimap(f, l, n, hf, key_equal(), a) {}  // C++14
337    unordered_multimap(initializer_list<value_type> il, size_type n, const allocator_type& a)
338      : unordered_multimap(il, n, hasher(), key_equal(), a) {}  // C++14
339    unordered_multimap(initializer_list<value_type> il, size_type n, const hasher& hf,
340      const allocator_type& a)
341      : unordered_multimap(il, n, hf, key_equal(), a) {}  // C++14
342    ~unordered_multimap();
343    unordered_multimap& operator=(const unordered_multimap&);
344    unordered_multimap& operator=(unordered_multimap&&)
345        noexcept(
346            allocator_type::propagate_on_container_move_assignment::value &&
347            is_nothrow_move_assignable<allocator_type>::value &&
348            is_nothrow_move_assignable<hasher>::value &&
349            is_nothrow_move_assignable<key_equal>::value);
350    unordered_multimap& operator=(initializer_list<value_type>);
351
352    allocator_type get_allocator() const noexcept;
353
354    bool      empty() const noexcept;
355    size_type size() const noexcept;
356    size_type max_size() const noexcept;
357
358    iterator       begin() noexcept;
359    iterator       end() noexcept;
360    const_iterator begin()  const noexcept;
361    const_iterator end()    const noexcept;
362    const_iterator cbegin() const noexcept;
363    const_iterator cend()   const noexcept;
364
365    template <class... Args>
366        iterator emplace(Args&&... args);
367    template <class... Args>
368        iterator emplace_hint(const_iterator position, Args&&... args);
369    iterator insert(const value_type& obj);
370    template <class P>
371        iterator insert(P&& obj);
372    iterator insert(const_iterator hint, const value_type& obj);
373    template <class P>
374        iterator insert(const_iterator hint, P&& obj);
375    template <class InputIterator>
376        void insert(InputIterator first, InputIterator last);
377    void insert(initializer_list<value_type>);
378
379    node_type extract(const_iterator position);                // C++17
380    node_type extract(const key_type& x);                      // C++17
381    iterator insert(node_type&& nh);                           // C++17
382    iterator insert(const_iterator hint, node_type&& nh);      // C++17
383
384    iterator erase(const_iterator position);
385    iterator erase(iterator position);  // C++14
386    size_type erase(const key_type& k);
387    iterator erase(const_iterator first, const_iterator last);
388    void clear() noexcept;
389
390    template<class H2, class P2>
391      void merge(unordered_multimap<Key, T, H2, P2, Allocator>& source);    // C++17
392    template<class H2, class P2>
393      void merge(unordered_multimap<Key, T, H2, P2, Allocator>&& source);   // C++17
394    template<class H2, class P2>
395      void merge(unordered_map<Key, T, H2, P2, Allocator>& source);         // C++17
396    template<class H2, class P2>
397      void merge(unordered_map<Key, T, H2, P2, Allocator>&& source);        // C++17
398
399    void swap(unordered_multimap&)
400        noexcept(
401            (!allocator_type::propagate_on_container_swap::value ||
402             __is_nothrow_swappable<allocator_type>::value) &&
403            __is_nothrow_swappable<hasher>::value &&
404            __is_nothrow_swappable<key_equal>::value);
405
406    hasher hash_function() const;
407    key_equal key_eq() const;
408
409    iterator       find(const key_type& k);
410    const_iterator find(const key_type& k) const;
411    template<typename K>
412        iterator find(const K& x);              // C++20
413    template<typename K>
414        const_iterator find(const K& x) const;  // C++20
415    size_type count(const key_type& k) const;
416    template<typename K>
417        size_type count(const K& k) const; // C++20
418    bool contains(const key_type& k) const; // C++20
419    template<typename K>
420        bool contains(const K& k) const; // C++20
421    pair<iterator, iterator>             equal_range(const key_type& k);
422    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
423    template<typename K>
424        pair<iterator, iterator>             equal_range(const K& k); // C++20
425    template<typename K>
426        pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
427
428    size_type bucket_count() const noexcept;
429    size_type max_bucket_count() const noexcept;
430
431    size_type bucket_size(size_type n) const;
432    size_type bucket(const key_type& k) const;
433
434    local_iterator       begin(size_type n);
435    local_iterator       end(size_type n);
436    const_local_iterator begin(size_type n) const;
437    const_local_iterator end(size_type n) const;
438    const_local_iterator cbegin(size_type n) const;
439    const_local_iterator cend(size_type n) const;
440
441    float load_factor() const noexcept;
442    float max_load_factor() const noexcept;
443    void max_load_factor(float z);
444    void rehash(size_type n);
445    void reserve(size_type n);
446};
447
448template<class InputIterator,
449    class Hash = hash<iter_key_t<InputIterator>>, class Pred = equal_to<iter_key_t<InputIterator>>,
450    class Allocator = allocator<iter_to_alloc_t<InputIterator>>>
451unordered_multimap(InputIterator, InputIterator, typename see below::size_type = see below,
452    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
453  -> unordered_multimap<iter_key_t<InputIterator>, iter_value_t<InputIterator>, Hash, Pred,
454    Allocator>; // C++17
455
456template<class Key, class T, class Hash = hash<Key>,
457    class Pred = equal_to<Key>, class Allocator = allocator<pair<const Key, T>>>
458unordered_multimap(initializer_list<pair<const Key, T>>, typename see below::size_type = see below,
459    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
460  -> unordered_multimap<Key, T, Hash, Pred, Allocator>; // C++17
461
462template<class InputIterator, class Allocator>
463unordered_multimap(InputIterator, InputIterator, typename see below::size_type, Allocator)
464  -> unordered_multimap<iter_key_t<InputIterator>, iter_val_t<InputIterator>,
465        hash<iter_key_t<InputIterator>>, equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
466
467template<class InputIterator, class Allocator>
468unordered_multimap(InputIterator, InputIterator, Allocator)
469  -> unordered_multimap<iter_key_t<InputIterator>, iter_val_t<InputIterator>,
470        hash<iter_key_t<InputIterator>>, equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
471
472template<class InputIterator, class Hash, class Allocator>
473unordered_multimap(InputIterator, InputIterator, typename see below::size_type, Hash, Allocator)
474  -> unordered_multimap<iter_key_t<InputIterator>, iter_val_t<InputIterator>, Hash,
475          equal_to<iter_key_t<InputIterator>>, Allocator>; // C++17
476
477template<class Key, class T, typename Allocator>
478unordered_multimap(initializer_list<pair<const Key, T>>, typename see below::size_type, Allocator)
479  -> unordered_multimap<Key, T, hash<Key>, equal_to<Key>, Allocator>; // C++17
480
481template<class Key, class T, typename Allocator>
482unordered_multimap(initializer_list<pair<const Key, T>>, Allocator)
483  -> unordered_multimap<Key, T, hash<Key>, equal_to<Key>, Allocator>; // C++17
484
485template<class Key, class T, class Hash, class Allocator>
486unordered_multimap(initializer_list<pair<const Key, T>>, typename see below::size_type, Hash,
487    Allocator)
488  -> unordered_multimap<Key, T, Hash, equal_to<Key>, Allocator>; // C++17
489
490template <class Key, class T, class Hash, class Pred, class Alloc>
491    void swap(unordered_multimap<Key, T, Hash, Pred, Alloc>& x,
492              unordered_multimap<Key, T, Hash, Pred, Alloc>& y)
493              noexcept(noexcept(x.swap(y)));
494
495template <class K, class T, class H, class P, class A, class Predicate>
496    typename unordered_map<K, T, H, P, A>::size_type
497    erase_if(unordered_map<K, T, H, P, A>& c, Predicate pred);       // C++20
498
499template <class K, class T, class H, class P, class A, class Predicate>
500    typename unordered_multimap<K, T, H, P, A>::size_type
501    erase_if(unordered_multimap<K, T, H, P, A>& c, Predicate pred);  // C++20
502
503template <class Key, class T, class Hash, class Pred, class Alloc>
504    bool
505    operator==(const unordered_multimap<Key, T, Hash, Pred, Alloc>& x,
506               const unordered_multimap<Key, T, Hash, Pred, Alloc>& y);
507
508template <class Key, class T, class Hash, class Pred, class Alloc>
509    bool
510    operator!=(const unordered_multimap<Key, T, Hash, Pred, Alloc>& x,
511               const unordered_multimap<Key, T, Hash, Pred, Alloc>& y);
512
513}  // std
514
515*/
516
517#include <__algorithm/is_permutation.h>
518#include <__assert> // all public C++ headers provide the assertion handler
519#include <__config>
520#include <__debug>
521#include <__functional/is_transparent.h>
522#include <__functional/operations.h>
523#include <__hash_table>
524#include <__iterator/distance.h>
525#include <__iterator/erase_if_container.h>
526#include <__iterator/iterator_traits.h>
527#include <__memory/addressof.h>
528#include <__memory/allocator.h>
529#include <__memory_resource/polymorphic_allocator.h>
530#include <__node_handle>
531#include <__type_traits/is_allocator.h>
532#include <__utility/forward.h>
533#include <stdexcept>
534#include <tuple>
535#include <version>
536
537// standard-mandated includes
538
539// [iterator.range]
540#include <__iterator/access.h>
541#include <__iterator/data.h>
542#include <__iterator/empty.h>
543#include <__iterator/reverse_access.h>
544#include <__iterator/size.h>
545
546// [unord.map.syn]
547#include <compare>
548#include <initializer_list>
549
550#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
551#  pragma GCC system_header
552#endif
553
554_LIBCPP_BEGIN_NAMESPACE_STD
555
556template <class _Key, class _Cp, class _Hash, class _Pred,
557          bool = is_empty<_Hash>::value && !__libcpp_is_final<_Hash>::value>
558class __unordered_map_hasher
559    : private _Hash
560{
561public:
562    _LIBCPP_INLINE_VISIBILITY
563    __unordered_map_hasher()
564        _NOEXCEPT_(is_nothrow_default_constructible<_Hash>::value)
565        : _Hash() {}
566    _LIBCPP_INLINE_VISIBILITY
567    __unordered_map_hasher(const _Hash& __h)
568        _NOEXCEPT_(is_nothrow_copy_constructible<_Hash>::value)
569        : _Hash(__h) {}
570    _LIBCPP_INLINE_VISIBILITY
571    const _Hash& hash_function() const _NOEXCEPT {return *this;}
572    _LIBCPP_INLINE_VISIBILITY
573    size_t operator()(const _Cp& __x) const
574        {return static_cast<const _Hash&>(*this)(__x.__get_value().first);}
575    _LIBCPP_INLINE_VISIBILITY
576    size_t operator()(const _Key& __x) const
577        {return static_cast<const _Hash&>(*this)(__x);}
578#if _LIBCPP_STD_VER > 17
579    template <typename _K2>
580    _LIBCPP_INLINE_VISIBILITY
581    size_t operator()(const _K2& __x) const
582        {return static_cast<const _Hash&>(*this)(__x);}
583#endif
584    _LIBCPP_INLINE_VISIBILITY
585    void swap(__unordered_map_hasher& __y)
586        _NOEXCEPT_(__is_nothrow_swappable<_Hash>::value)
587    {
588        using _VSTD::swap;
589        swap(static_cast<_Hash&>(*this), static_cast<_Hash&>(__y));
590    }
591};
592
593template <class _Key, class _Cp, class _Hash, class _Pred>
594class __unordered_map_hasher<_Key, _Cp, _Hash, _Pred, false>
595{
596    _Hash __hash_;
597public:
598    _LIBCPP_INLINE_VISIBILITY
599    __unordered_map_hasher()
600        _NOEXCEPT_(is_nothrow_default_constructible<_Hash>::value)
601        : __hash_() {}
602    _LIBCPP_INLINE_VISIBILITY
603    __unordered_map_hasher(const _Hash& __h)
604        _NOEXCEPT_(is_nothrow_copy_constructible<_Hash>::value)
605        : __hash_(__h) {}
606    _LIBCPP_INLINE_VISIBILITY
607    const _Hash& hash_function() const _NOEXCEPT {return __hash_;}
608    _LIBCPP_INLINE_VISIBILITY
609    size_t operator()(const _Cp& __x) const
610        {return __hash_(__x.__get_value().first);}
611    _LIBCPP_INLINE_VISIBILITY
612    size_t operator()(const _Key& __x) const
613        {return __hash_(__x);}
614#if _LIBCPP_STD_VER > 17
615    template <typename _K2>
616    _LIBCPP_INLINE_VISIBILITY
617    size_t operator()(const _K2& __x) const
618        {return __hash_(__x);}
619#endif
620    _LIBCPP_INLINE_VISIBILITY
621    void swap(__unordered_map_hasher& __y)
622        _NOEXCEPT_(__is_nothrow_swappable<_Hash>::value)
623    {
624        using _VSTD::swap;
625        swap(__hash_, __y.__hash_);
626    }
627};
628
629template <class _Key, class _Cp, class _Hash, class _Pred, bool __b>
630inline _LIBCPP_INLINE_VISIBILITY
631void
632swap(__unordered_map_hasher<_Key, _Cp, _Hash, _Pred, __b>& __x,
633     __unordered_map_hasher<_Key, _Cp, _Hash, _Pred, __b>& __y)
634    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
635{
636    __x.swap(__y);
637}
638
639template <class _Key, class _Cp, class _Pred, class _Hash,
640          bool = is_empty<_Pred>::value && !__libcpp_is_final<_Pred>::value>
641class __unordered_map_equal
642    : private _Pred
643{
644public:
645    _LIBCPP_INLINE_VISIBILITY
646    __unordered_map_equal()
647        _NOEXCEPT_(is_nothrow_default_constructible<_Pred>::value)
648        : _Pred() {}
649    _LIBCPP_INLINE_VISIBILITY
650    __unordered_map_equal(const _Pred& __p)
651        _NOEXCEPT_(is_nothrow_copy_constructible<_Pred>::value)
652        : _Pred(__p) {}
653    _LIBCPP_INLINE_VISIBILITY
654    const _Pred& key_eq() const _NOEXCEPT {return *this;}
655    _LIBCPP_INLINE_VISIBILITY
656    bool operator()(const _Cp& __x, const _Cp& __y) const
657        {return static_cast<const _Pred&>(*this)(__x.__get_value().first, __y.__get_value().first);}
658    _LIBCPP_INLINE_VISIBILITY
659    bool operator()(const _Cp& __x, const _Key& __y) const
660        {return static_cast<const _Pred&>(*this)(__x.__get_value().first, __y);}
661    _LIBCPP_INLINE_VISIBILITY
662    bool operator()(const _Key& __x, const _Cp& __y) const
663        {return static_cast<const _Pred&>(*this)(__x, __y.__get_value().first);}
664#if _LIBCPP_STD_VER > 17
665    template <typename _K2>
666    _LIBCPP_INLINE_VISIBILITY
667    bool operator()(const _Cp& __x, const _K2& __y) const
668        {return static_cast<const _Pred&>(*this)(__x.__get_value().first, __y);}
669    template <typename _K2>
670    _LIBCPP_INLINE_VISIBILITY
671    bool operator()(const _K2& __x, const _Cp& __y) const
672        {return static_cast<const _Pred&>(*this)(__x, __y.__get_value().first);}
673    template <typename _K2>
674    _LIBCPP_INLINE_VISIBILITY
675    bool operator()(const _Key& __x, const _K2& __y) const
676        {return static_cast<const _Pred&>(*this)(__x, __y);}
677    template <typename _K2>
678    _LIBCPP_INLINE_VISIBILITY
679    bool operator()(const _K2& __x, const _Key& __y) const
680        {return static_cast<const _Pred&>(*this)(__x, __y);}
681#endif
682    _LIBCPP_INLINE_VISIBILITY
683    void swap(__unordered_map_equal& __y)
684        _NOEXCEPT_(__is_nothrow_swappable<_Pred>::value)
685    {
686        using _VSTD::swap;
687        swap(static_cast<_Pred&>(*this), static_cast<_Pred&>(__y));
688    }
689};
690
691template <class _Key, class _Cp, class _Pred, class _Hash>
692class __unordered_map_equal<_Key, _Cp, _Pred, _Hash, false>
693{
694    _Pred __pred_;
695public:
696    _LIBCPP_INLINE_VISIBILITY
697    __unordered_map_equal()
698        _NOEXCEPT_(is_nothrow_default_constructible<_Pred>::value)
699        : __pred_() {}
700    _LIBCPP_INLINE_VISIBILITY
701    __unordered_map_equal(const _Pred& __p)
702        _NOEXCEPT_(is_nothrow_copy_constructible<_Pred>::value)
703        : __pred_(__p) {}
704    _LIBCPP_INLINE_VISIBILITY
705    const _Pred& key_eq() const _NOEXCEPT {return __pred_;}
706    _LIBCPP_INLINE_VISIBILITY
707    bool operator()(const _Cp& __x, const _Cp& __y) const
708        {return __pred_(__x.__get_value().first, __y.__get_value().first);}
709    _LIBCPP_INLINE_VISIBILITY
710    bool operator()(const _Cp& __x, const _Key& __y) const
711        {return __pred_(__x.__get_value().first, __y);}
712    _LIBCPP_INLINE_VISIBILITY
713    bool operator()(const _Key& __x, const _Cp& __y) const
714        {return __pred_(__x, __y.__get_value().first);}
715#if _LIBCPP_STD_VER > 17
716    template <typename _K2>
717    _LIBCPP_INLINE_VISIBILITY
718    bool operator()(const _Cp& __x, const _K2& __y) const
719        {return __pred_(__x.__get_value().first, __y);}
720    template <typename _K2>
721    _LIBCPP_INLINE_VISIBILITY
722    bool operator()(const _K2& __x, const _Cp& __y) const
723        {return __pred_(__x, __y.__get_value().first);}
724    template <typename _K2>
725    _LIBCPP_INLINE_VISIBILITY
726    bool operator()(const _Key& __x, const _K2& __y) const
727        {return __pred_(__x, __y);}
728    template <typename _K2>
729    _LIBCPP_INLINE_VISIBILITY
730    bool operator()(const _K2& __x, const _Key& __y) const
731        {return __pred_(__x, __y);}
732#endif
733    _LIBCPP_INLINE_VISIBILITY
734    void swap(__unordered_map_equal& __y)
735        _NOEXCEPT_(__is_nothrow_swappable<_Pred>::value)
736    {
737        using _VSTD::swap;
738        swap(__pred_, __y.__pred_);
739    }
740};
741
742template <class _Key, class _Cp, class _Pred, class _Hash, bool __b>
743inline _LIBCPP_INLINE_VISIBILITY
744void
745swap(__unordered_map_equal<_Key, _Cp, _Pred, _Hash, __b>& __x,
746     __unordered_map_equal<_Key, _Cp, _Pred, _Hash, __b>& __y)
747    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
748{
749    __x.swap(__y);
750}
751
752template <class _Alloc>
753class __hash_map_node_destructor
754{
755    typedef _Alloc                              allocator_type;
756    typedef allocator_traits<allocator_type>    __alloc_traits;
757
758public:
759
760    typedef typename __alloc_traits::pointer       pointer;
761private:
762
763    allocator_type& __na_;
764
765    __hash_map_node_destructor& operator=(const __hash_map_node_destructor&);
766
767public:
768    bool __first_constructed;
769    bool __second_constructed;
770
771    _LIBCPP_INLINE_VISIBILITY
772    explicit __hash_map_node_destructor(allocator_type& __na) _NOEXCEPT
773        : __na_(__na),
774          __first_constructed(false),
775          __second_constructed(false)
776        {}
777
778#ifndef _LIBCPP_CXX03_LANG
779    _LIBCPP_INLINE_VISIBILITY
780    __hash_map_node_destructor(__hash_node_destructor<allocator_type>&& __x)
781        _NOEXCEPT
782        : __na_(__x.__na_),
783          __first_constructed(__x.__value_constructed),
784          __second_constructed(__x.__value_constructed)
785        {
786            __x.__value_constructed = false;
787        }
788#else  // _LIBCPP_CXX03_LANG
789    _LIBCPP_INLINE_VISIBILITY
790    __hash_map_node_destructor(const __hash_node_destructor<allocator_type>& __x)
791        : __na_(__x.__na_),
792          __first_constructed(__x.__value_constructed),
793          __second_constructed(__x.__value_constructed)
794        {
795            const_cast<bool&>(__x.__value_constructed) = false;
796        }
797#endif // _LIBCPP_CXX03_LANG
798
799    _LIBCPP_INLINE_VISIBILITY
800    void operator()(pointer __p) _NOEXCEPT
801    {
802        if (__second_constructed)
803            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.__get_value().second));
804        if (__first_constructed)
805            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.__get_value().first));
806        if (__p)
807            __alloc_traits::deallocate(__na_, __p, 1);
808    }
809};
810
811#ifndef _LIBCPP_CXX03_LANG
812template <class _Key, class _Tp>
813struct _LIBCPP_STANDALONE_DEBUG __hash_value_type
814{
815    typedef _Key                                     key_type;
816    typedef _Tp                                      mapped_type;
817    typedef pair<const key_type, mapped_type>        value_type;
818    typedef pair<key_type&, mapped_type&>            __nc_ref_pair_type;
819    typedef pair<key_type&&, mapped_type&&>          __nc_rref_pair_type;
820
821private:
822    value_type __cc_;
823
824public:
825    _LIBCPP_INLINE_VISIBILITY
826    value_type& __get_value()
827    {
828#if _LIBCPP_STD_VER > 14
829        return *_VSTD::launder(_VSTD::addressof(__cc_));
830#else
831        return __cc_;
832#endif
833    }
834
835    _LIBCPP_INLINE_VISIBILITY
836    const value_type& __get_value() const
837    {
838#if _LIBCPP_STD_VER > 14
839        return *_VSTD::launder(_VSTD::addressof(__cc_));
840#else
841        return __cc_;
842#endif
843    }
844
845    _LIBCPP_INLINE_VISIBILITY
846    __nc_ref_pair_type __ref()
847    {
848        value_type& __v = __get_value();
849        return __nc_ref_pair_type(const_cast<key_type&>(__v.first), __v.second);
850    }
851
852    _LIBCPP_INLINE_VISIBILITY
853    __nc_rref_pair_type __move()
854    {
855        value_type& __v = __get_value();
856        return __nc_rref_pair_type(
857            _VSTD::move(const_cast<key_type&>(__v.first)),
858            _VSTD::move(__v.second));
859    }
860
861    _LIBCPP_INLINE_VISIBILITY
862    __hash_value_type& operator=(const __hash_value_type& __v)
863    {
864        __ref() = __v.__get_value();
865        return *this;
866    }
867
868    _LIBCPP_INLINE_VISIBILITY
869    __hash_value_type& operator=(__hash_value_type&& __v)
870    {
871        __ref() = __v.__move();
872        return *this;
873    }
874
875    template <class _ValueTp,
876              class = __enable_if_t<__is_same_uncvref<_ValueTp, value_type>::value>
877             >
878    _LIBCPP_INLINE_VISIBILITY
879    __hash_value_type& operator=(_ValueTp&& __v)
880    {
881        __ref() = _VSTD::forward<_ValueTp>(__v);
882        return *this;
883    }
884
885private:
886    __hash_value_type(const __hash_value_type& __v) = delete;
887    __hash_value_type(__hash_value_type&& __v) = delete;
888    template <class ..._Args>
889    explicit __hash_value_type(_Args&& ...__args) = delete;
890
891    ~__hash_value_type() = delete;
892};
893
894#else
895
896template <class _Key, class _Tp>
897struct __hash_value_type
898{
899    typedef _Key                                     key_type;
900    typedef _Tp                                      mapped_type;
901    typedef pair<const key_type, mapped_type>        value_type;
902
903private:
904    value_type __cc_;
905
906public:
907    _LIBCPP_INLINE_VISIBILITY
908    value_type& __get_value() { return __cc_; }
909    _LIBCPP_INLINE_VISIBILITY
910    const value_type& __get_value() const { return __cc_; }
911
912private:
913   ~__hash_value_type();
914};
915
916#endif
917
918template <class _HashIterator>
919class _LIBCPP_TEMPLATE_VIS __hash_map_iterator
920{
921    _HashIterator __i_;
922
923    typedef  __hash_node_types_from_iterator<_HashIterator> _NodeTypes;
924
925public:
926    typedef forward_iterator_tag                                 iterator_category;
927    typedef typename _NodeTypes::__map_value_type                value_type;
928    typedef typename _NodeTypes::difference_type                 difference_type;
929    typedef value_type&                                          reference;
930    typedef typename _NodeTypes::__map_value_type_pointer       pointer;
931
932    _LIBCPP_INLINE_VISIBILITY
933    __hash_map_iterator() _NOEXCEPT {}
934
935    _LIBCPP_INLINE_VISIBILITY
936    __hash_map_iterator(_HashIterator __i) _NOEXCEPT : __i_(__i) {}
937
938    _LIBCPP_INLINE_VISIBILITY
939    reference operator*() const {return __i_->__get_value();}
940    _LIBCPP_INLINE_VISIBILITY
941    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__i_->__get_value());}
942
943    _LIBCPP_INLINE_VISIBILITY
944    __hash_map_iterator& operator++() {++__i_; return *this;}
945    _LIBCPP_INLINE_VISIBILITY
946    __hash_map_iterator operator++(int)
947    {
948        __hash_map_iterator __t(*this);
949        ++(*this);
950        return __t;
951    }
952
953    friend _LIBCPP_INLINE_VISIBILITY
954        bool operator==(const __hash_map_iterator& __x, const __hash_map_iterator& __y)
955        {return __x.__i_ == __y.__i_;}
956    friend _LIBCPP_INLINE_VISIBILITY
957        bool operator!=(const __hash_map_iterator& __x, const __hash_map_iterator& __y)
958        {return __x.__i_ != __y.__i_;}
959
960    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_map;
961    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
962    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
963    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
964    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
965};
966
967template <class _HashIterator>
968class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator
969{
970    _HashIterator __i_;
971
972    typedef  __hash_node_types_from_iterator<_HashIterator> _NodeTypes;
973
974public:
975    typedef forward_iterator_tag                                 iterator_category;
976    typedef typename _NodeTypes::__map_value_type                value_type;
977    typedef typename _NodeTypes::difference_type                 difference_type;
978    typedef const value_type&                                    reference;
979    typedef typename _NodeTypes::__const_map_value_type_pointer  pointer;
980
981    _LIBCPP_INLINE_VISIBILITY
982    __hash_map_const_iterator() _NOEXCEPT {}
983
984    _LIBCPP_INLINE_VISIBILITY
985    __hash_map_const_iterator(_HashIterator __i) _NOEXCEPT : __i_(__i) {}
986    _LIBCPP_INLINE_VISIBILITY
987    __hash_map_const_iterator(
988            __hash_map_iterator<typename _HashIterator::__non_const_iterator> __i)
989                 _NOEXCEPT
990                : __i_(__i.__i_) {}
991
992    _LIBCPP_INLINE_VISIBILITY
993    reference operator*() const {return __i_->__get_value();}
994    _LIBCPP_INLINE_VISIBILITY
995    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__i_->__get_value());}
996
997    _LIBCPP_INLINE_VISIBILITY
998    __hash_map_const_iterator& operator++() {++__i_; return *this;}
999    _LIBCPP_INLINE_VISIBILITY
1000    __hash_map_const_iterator operator++(int)
1001    {
1002        __hash_map_const_iterator __t(*this);
1003        ++(*this);
1004        return __t;
1005    }
1006
1007    friend _LIBCPP_INLINE_VISIBILITY
1008        bool operator==(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y)
1009        {return __x.__i_ == __y.__i_;}
1010    friend _LIBCPP_INLINE_VISIBILITY
1011        bool operator!=(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y)
1012        {return __x.__i_ != __y.__i_;}
1013
1014    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_map;
1015    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
1016    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
1017    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
1018};
1019
1020template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1021class unordered_multimap;
1022
1023template <class _Key, class _Tp, class _Hash = hash<_Key>, class _Pred = equal_to<_Key>,
1024          class _Alloc = allocator<pair<const _Key, _Tp> > >
1025class _LIBCPP_TEMPLATE_VIS unordered_map
1026{
1027public:
1028    // types
1029    typedef _Key                                           key_type;
1030    typedef _Tp                                            mapped_type;
1031    typedef __type_identity_t<_Hash>                       hasher;
1032    typedef __type_identity_t<_Pred>                       key_equal;
1033    typedef __type_identity_t<_Alloc>                      allocator_type;
1034    typedef pair<const key_type, mapped_type>              value_type;
1035    typedef value_type&                                    reference;
1036    typedef const value_type&                              const_reference;
1037    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
1038                  "Invalid allocator::value_type");
1039
1040private:
1041    typedef __hash_value_type<key_type, mapped_type>                          __value_type;
1042    typedef __unordered_map_hasher<key_type, __value_type, hasher, key_equal> __hasher;
1043    typedef __unordered_map_equal<key_type, __value_type, key_equal, hasher>  __key_equal;
1044    typedef __rebind_alloc<allocator_traits<allocator_type>, __value_type>    __allocator_type;
1045
1046    typedef __hash_table<__value_type, __hasher,
1047                         __key_equal,  __allocator_type>   __table;
1048
1049    __table __table_;
1050
1051    typedef typename __table::_NodeTypes                   _NodeTypes;
1052    typedef typename __table::__node_pointer               __node_pointer;
1053    typedef typename __table::__node_const_pointer         __node_const_pointer;
1054    typedef typename __table::__node_traits                __node_traits;
1055    typedef typename __table::__node_allocator             __node_allocator;
1056    typedef typename __table::__node                       __node;
1057    typedef __hash_map_node_destructor<__node_allocator>   _Dp;
1058    typedef unique_ptr<__node, _Dp>                         __node_holder;
1059    typedef allocator_traits<allocator_type>               __alloc_traits;
1060
1061    static_assert(is_same<allocator_type, __rebind_alloc<__alloc_traits, value_type> >::value,
1062                  "[allocator.requirements] states that rebinding an allocator to the same type should result in the "
1063                  "original allocator");
1064
1065    static_assert((is_same<typename __table::__container_value_type, value_type>::value), "");
1066    static_assert((is_same<typename __table::__node_value_type, __value_type>::value), "");
1067public:
1068    typedef typename __alloc_traits::pointer         pointer;
1069    typedef typename __alloc_traits::const_pointer   const_pointer;
1070    typedef typename __table::size_type              size_type;
1071    typedef typename __table::difference_type        difference_type;
1072
1073    typedef __hash_map_iterator<typename __table::iterator>       iterator;
1074    typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
1075    typedef __hash_map_iterator<typename __table::local_iterator> local_iterator;
1076    typedef __hash_map_const_iterator<typename __table::const_local_iterator> const_local_iterator;
1077
1078#if _LIBCPP_STD_VER > 14
1079    typedef __map_node_handle<__node, allocator_type> node_type;
1080    typedef __insert_return_type<iterator, node_type> insert_return_type;
1081#endif
1082
1083    template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
1084        friend class _LIBCPP_TEMPLATE_VIS unordered_map;
1085    template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
1086        friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
1087
1088    _LIBCPP_INLINE_VISIBILITY
1089    unordered_map()
1090        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
1091    {
1092        _VSTD::__debug_db_insert_c(this);
1093    }
1094    explicit unordered_map(size_type __n, const hasher& __hf = hasher(),
1095                           const key_equal& __eql = key_equal());
1096    unordered_map(size_type __n, const hasher& __hf,
1097                  const key_equal& __eql,
1098                  const allocator_type& __a);
1099    template <class _InputIterator>
1100        unordered_map(_InputIterator __first, _InputIterator __last);
1101    template <class _InputIterator>
1102        unordered_map(_InputIterator __first, _InputIterator __last,
1103                      size_type __n, const hasher& __hf = hasher(),
1104                      const key_equal& __eql = key_equal());
1105    template <class _InputIterator>
1106        unordered_map(_InputIterator __first, _InputIterator __last,
1107                      size_type __n, const hasher& __hf,
1108                      const key_equal& __eql,
1109                      const allocator_type& __a);
1110    _LIBCPP_INLINE_VISIBILITY
1111    explicit unordered_map(const allocator_type& __a);
1112    unordered_map(const unordered_map& __u);
1113    unordered_map(const unordered_map& __u, const allocator_type& __a);
1114#ifndef _LIBCPP_CXX03_LANG
1115    _LIBCPP_INLINE_VISIBILITY
1116    unordered_map(unordered_map&& __u)
1117        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
1118    unordered_map(unordered_map&& __u, const allocator_type& __a);
1119    unordered_map(initializer_list<value_type> __il);
1120    unordered_map(initializer_list<value_type> __il, size_type __n,
1121                  const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
1122    unordered_map(initializer_list<value_type> __il, size_type __n,
1123                  const hasher& __hf, const key_equal& __eql,
1124                  const allocator_type& __a);
1125#endif // _LIBCPP_CXX03_LANG
1126#if _LIBCPP_STD_VER > 11
1127    _LIBCPP_INLINE_VISIBILITY
1128    unordered_map(size_type __n, const allocator_type& __a)
1129      : unordered_map(__n, hasher(), key_equal(), __a) {}
1130    _LIBCPP_INLINE_VISIBILITY
1131    unordered_map(size_type __n, const hasher& __hf, const allocator_type& __a)
1132      : unordered_map(__n, __hf, key_equal(), __a) {}
1133    template <class _InputIterator>
1134    _LIBCPP_INLINE_VISIBILITY
1135      unordered_map(_InputIterator __first, _InputIterator __last, size_type __n, const allocator_type& __a)
1136      : unordered_map(__first, __last, __n, hasher(), key_equal(), __a) {}
1137    template <class _InputIterator>
1138    _LIBCPP_INLINE_VISIBILITY
1139      unordered_map(_InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf,
1140        const allocator_type& __a)
1141      : unordered_map(__first, __last, __n, __hf, key_equal(), __a) {}
1142    _LIBCPP_INLINE_VISIBILITY
1143    unordered_map(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
1144      : unordered_map(__il, __n, hasher(), key_equal(), __a) {}
1145    _LIBCPP_INLINE_VISIBILITY
1146    unordered_map(initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1147      const allocator_type& __a)
1148      : unordered_map(__il, __n, __hf, key_equal(), __a) {}
1149#endif
1150    _LIBCPP_INLINE_VISIBILITY
1151    ~unordered_map() {
1152        static_assert(sizeof(std::__diagnose_unordered_container_requirements<_Key, _Hash, _Pred>(0)), "");
1153    }
1154
1155    _LIBCPP_INLINE_VISIBILITY
1156    unordered_map& operator=(const unordered_map& __u)
1157    {
1158#ifndef _LIBCPP_CXX03_LANG
1159        __table_ = __u.__table_;
1160#else
1161        if (this != _VSTD::addressof(__u)) {
1162            __table_.clear();
1163            __table_.hash_function() = __u.__table_.hash_function();
1164            __table_.key_eq() = __u.__table_.key_eq();
1165            __table_.max_load_factor() = __u.__table_.max_load_factor();
1166            __table_.__copy_assign_alloc(__u.__table_);
1167            insert(__u.begin(), __u.end());
1168        }
1169#endif
1170        return *this;
1171    }
1172#ifndef _LIBCPP_CXX03_LANG
1173    _LIBCPP_INLINE_VISIBILITY
1174    unordered_map& operator=(unordered_map&& __u)
1175        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
1176    _LIBCPP_INLINE_VISIBILITY
1177    unordered_map& operator=(initializer_list<value_type> __il);
1178#endif // _LIBCPP_CXX03_LANG
1179
1180    _LIBCPP_INLINE_VISIBILITY
1181    allocator_type get_allocator() const _NOEXCEPT
1182        {return allocator_type(__table_.__node_alloc());}
1183
1184    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1185    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
1186    _LIBCPP_INLINE_VISIBILITY
1187    size_type size() const _NOEXCEPT  {return __table_.size();}
1188    _LIBCPP_INLINE_VISIBILITY
1189    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
1190
1191    _LIBCPP_INLINE_VISIBILITY
1192    iterator       begin() _NOEXCEPT        {return __table_.begin();}
1193    _LIBCPP_INLINE_VISIBILITY
1194    iterator       end() _NOEXCEPT          {return __table_.end();}
1195    _LIBCPP_INLINE_VISIBILITY
1196    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
1197    _LIBCPP_INLINE_VISIBILITY
1198    const_iterator end()    const _NOEXCEPT {return __table_.end();}
1199    _LIBCPP_INLINE_VISIBILITY
1200    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
1201    _LIBCPP_INLINE_VISIBILITY
1202    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
1203
1204    _LIBCPP_INLINE_VISIBILITY
1205    pair<iterator, bool> insert(const value_type& __x)
1206        {return __table_.__insert_unique(__x);}
1207
1208    iterator insert(const_iterator __p, const value_type& __x) {
1209        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
1210                             "unordered_map::insert(const_iterator, const value_type&) called with an iterator not "
1211                             "referring to this unordered_map");
1212        ((void)__p);
1213        return insert(__x).first;
1214    }
1215
1216    template <class _InputIterator>
1217        _LIBCPP_INLINE_VISIBILITY
1218        void insert(_InputIterator __first, _InputIterator __last);
1219
1220#ifndef _LIBCPP_CXX03_LANG
1221    _LIBCPP_INLINE_VISIBILITY
1222    void insert(initializer_list<value_type> __il)
1223        {insert(__il.begin(), __il.end());}
1224
1225    _LIBCPP_INLINE_VISIBILITY
1226    pair<iterator, bool> insert(value_type&& __x)
1227        {return __table_.__insert_unique(_VSTD::move(__x));}
1228
1229    iterator insert(const_iterator __p, value_type&& __x) {
1230        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
1231                             "unordered_map::insert(const_iterator, const value_type&) called with an iterator not"
1232                             " referring to this unordered_map");
1233        ((void)__p);
1234        return __table_.__insert_unique(_VSTD::move(__x)).first;
1235    }
1236
1237    template <class _Pp,
1238              class = __enable_if_t<is_constructible<value_type, _Pp>::value> >
1239        _LIBCPP_INLINE_VISIBILITY
1240        pair<iterator, bool> insert(_Pp&& __x)
1241            {return __table_.__insert_unique(_VSTD::forward<_Pp>(__x));}
1242
1243    template <class _Pp,
1244              class = __enable_if_t<is_constructible<value_type, _Pp>::value> >
1245        _LIBCPP_INLINE_VISIBILITY
1246        iterator insert(const_iterator __p, _Pp&& __x)
1247        {
1248            _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
1249                                 "unordered_map::insert(const_iterator, value_type&&) called with an iterator not"
1250                                 " referring to this unordered_map");
1251          ((void)__p);
1252            return insert(_VSTD::forward<_Pp>(__x)).first;
1253        }
1254
1255    template <class... _Args>
1256    _LIBCPP_INLINE_VISIBILITY
1257    pair<iterator, bool> emplace(_Args&&... __args) {
1258        return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...);
1259    }
1260
1261    template <class... _Args>
1262    _LIBCPP_INLINE_VISIBILITY
1263    iterator emplace_hint(const_iterator __p, _Args&&... __args) {
1264        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
1265                             "unordered_map::emplace_hint(const_iterator, args...) called with an iterator not"
1266                             " referring to this unordered_map");
1267          ((void)__p);
1268        return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...).first;
1269    }
1270
1271#endif // _LIBCPP_CXX03_LANG
1272
1273#if _LIBCPP_STD_VER > 14
1274    template <class... _Args>
1275        _LIBCPP_INLINE_VISIBILITY
1276        pair<iterator, bool> try_emplace(const key_type& __k, _Args&&... __args)
1277    {
1278        return __table_.__emplace_unique_key_args(__k, piecewise_construct,
1279            _VSTD::forward_as_tuple(__k),
1280            _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
1281    }
1282
1283    template <class... _Args>
1284        _LIBCPP_INLINE_VISIBILITY
1285        pair<iterator, bool> try_emplace(key_type&& __k, _Args&&... __args)
1286    {
1287        return __table_.__emplace_unique_key_args(__k, piecewise_construct,
1288            _VSTD::forward_as_tuple(_VSTD::move(__k)),
1289            _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
1290    }
1291
1292    template <class... _Args>
1293        _LIBCPP_INLINE_VISIBILITY
1294        iterator try_emplace(const_iterator __h, const key_type& __k, _Args&&... __args)
1295    {
1296        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__h)) == this,
1297                             "unordered_map::try_emplace(const_iterator, key, args...) called with an iterator not"
1298                             " referring to this unordered_map");
1299        ((void)__h);
1300        return try_emplace(__k, _VSTD::forward<_Args>(__args)...).first;
1301    }
1302
1303    template <class... _Args>
1304        _LIBCPP_INLINE_VISIBILITY
1305        iterator try_emplace(const_iterator __h, key_type&& __k, _Args&&... __args)
1306    {
1307        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__h)) == this,
1308                             "unordered_map::try_emplace(const_iterator, key, args...) called with an iterator not"
1309                             " referring to this unordered_map");
1310        ((void)__h);
1311        return try_emplace(_VSTD::move(__k), _VSTD::forward<_Args>(__args)...).first;
1312    }
1313
1314    template <class _Vp>
1315        _LIBCPP_INLINE_VISIBILITY
1316        pair<iterator, bool> insert_or_assign(const key_type& __k, _Vp&& __v)
1317    {
1318        pair<iterator, bool> __res = __table_.__emplace_unique_key_args(__k,
1319            __k, _VSTD::forward<_Vp>(__v));
1320        if (!__res.second) {
1321            __res.first->second = _VSTD::forward<_Vp>(__v);
1322        }
1323        return __res;
1324    }
1325
1326    template <class _Vp>
1327        _LIBCPP_INLINE_VISIBILITY
1328        pair<iterator, bool> insert_or_assign(key_type&& __k, _Vp&& __v)
1329    {
1330        pair<iterator, bool> __res = __table_.__emplace_unique_key_args(__k,
1331            _VSTD::move(__k), _VSTD::forward<_Vp>(__v));
1332        if (!__res.second) {
1333            __res.first->second = _VSTD::forward<_Vp>(__v);
1334        }
1335        return __res;
1336    }
1337
1338    template <class _Vp>
1339        _LIBCPP_INLINE_VISIBILITY
1340        iterator insert_or_assign(const_iterator, const key_type& __k, _Vp&& __v)
1341     {
1342          // FIXME: Add debug mode checking for the iterator input
1343          return insert_or_assign(__k, _VSTD::forward<_Vp>(__v)).first;
1344     }
1345
1346    template <class _Vp>
1347        _LIBCPP_INLINE_VISIBILITY
1348        iterator insert_or_assign(const_iterator, key_type&& __k, _Vp&& __v)
1349     {
1350        // FIXME: Add debug mode checking for the iterator input
1351        return insert_or_assign(_VSTD::move(__k), _VSTD::forward<_Vp>(__v)).first;
1352     }
1353#endif // _LIBCPP_STD_VER > 14
1354
1355    _LIBCPP_INLINE_VISIBILITY
1356    iterator erase(const_iterator __p) {return __table_.erase(__p.__i_);}
1357    _LIBCPP_INLINE_VISIBILITY
1358    iterator erase(iterator __p)       {return __table_.erase(__p.__i_);}
1359    _LIBCPP_INLINE_VISIBILITY
1360    size_type erase(const key_type& __k) {return __table_.__erase_unique(__k);}
1361    _LIBCPP_INLINE_VISIBILITY
1362    iterator erase(const_iterator __first, const_iterator __last)
1363        {return __table_.erase(__first.__i_, __last.__i_);}
1364    _LIBCPP_INLINE_VISIBILITY
1365        void clear() _NOEXCEPT {__table_.clear();}
1366
1367#if _LIBCPP_STD_VER > 14
1368    _LIBCPP_INLINE_VISIBILITY
1369    insert_return_type insert(node_type&& __nh)
1370    {
1371        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1372            "node_type with incompatible allocator passed to unordered_map::insert()");
1373        return __table_.template __node_handle_insert_unique<
1374            node_type, insert_return_type>(_VSTD::move(__nh));
1375    }
1376    _LIBCPP_INLINE_VISIBILITY
1377    iterator insert(const_iterator __hint, node_type&& __nh)
1378    {
1379        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1380            "node_type with incompatible allocator passed to unordered_map::insert()");
1381        return __table_.template __node_handle_insert_unique<node_type>(
1382            __hint.__i_, _VSTD::move(__nh));
1383    }
1384    _LIBCPP_INLINE_VISIBILITY
1385    node_type extract(key_type const& __key)
1386    {
1387        return __table_.template __node_handle_extract<node_type>(__key);
1388    }
1389    _LIBCPP_INLINE_VISIBILITY
1390    node_type extract(const_iterator __it)
1391    {
1392        return __table_.template __node_handle_extract<node_type>(
1393            __it.__i_);
1394    }
1395
1396    template <class _H2, class _P2>
1397    _LIBCPP_INLINE_VISIBILITY
1398    void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>& __source)
1399    {
1400        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1401                       "merging container with incompatible allocator");
1402        return __table_.__node_handle_merge_unique(__source.__table_);
1403    }
1404    template <class _H2, class _P2>
1405    _LIBCPP_INLINE_VISIBILITY
1406    void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>&& __source)
1407    {
1408        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1409                       "merging container with incompatible allocator");
1410        return __table_.__node_handle_merge_unique(__source.__table_);
1411    }
1412    template <class _H2, class _P2>
1413    _LIBCPP_INLINE_VISIBILITY
1414    void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>& __source)
1415    {
1416        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1417                       "merging container with incompatible allocator");
1418        return __table_.__node_handle_merge_unique(__source.__table_);
1419    }
1420    template <class _H2, class _P2>
1421    _LIBCPP_INLINE_VISIBILITY
1422    void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>&& __source)
1423    {
1424        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1425                       "merging container with incompatible allocator");
1426        return __table_.__node_handle_merge_unique(__source.__table_);
1427    }
1428#endif
1429
1430    _LIBCPP_INLINE_VISIBILITY
1431    void swap(unordered_map& __u)
1432        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
1433        { __table_.swap(__u.__table_);}
1434
1435    _LIBCPP_INLINE_VISIBILITY
1436    hasher hash_function() const
1437        {return __table_.hash_function().hash_function();}
1438    _LIBCPP_INLINE_VISIBILITY
1439    key_equal key_eq() const
1440        {return __table_.key_eq().key_eq();}
1441
1442    _LIBCPP_INLINE_VISIBILITY
1443    iterator       find(const key_type& __k)       {return __table_.find(__k);}
1444    _LIBCPP_INLINE_VISIBILITY
1445    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
1446#if _LIBCPP_STD_VER > 17
1447    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1448    _LIBCPP_INLINE_VISIBILITY
1449    iterator       find(const _K2& __k)            {return __table_.find(__k);}
1450    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1451    _LIBCPP_INLINE_VISIBILITY
1452    const_iterator find(const _K2& __k) const      {return __table_.find(__k);}
1453#endif // _LIBCPP_STD_VER > 17
1454
1455    _LIBCPP_INLINE_VISIBILITY
1456    size_type count(const key_type& __k) const {return __table_.__count_unique(__k);}
1457#if _LIBCPP_STD_VER > 17
1458    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1459    _LIBCPP_INLINE_VISIBILITY
1460    size_type count(const _K2& __k) const      {return __table_.__count_unique(__k);}
1461#endif // _LIBCPP_STD_VER > 17
1462
1463#if _LIBCPP_STD_VER > 17
1464    _LIBCPP_INLINE_VISIBILITY
1465    bool contains(const key_type& __k) const {return find(__k) != end();}
1466
1467    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1468    _LIBCPP_INLINE_VISIBILITY
1469    bool contains(const _K2& __k) const      {return find(__k) != end();}
1470#endif // _LIBCPP_STD_VER > 17
1471
1472    _LIBCPP_INLINE_VISIBILITY
1473    pair<iterator, iterator>             equal_range(const key_type& __k)
1474        {return __table_.__equal_range_unique(__k);}
1475    _LIBCPP_INLINE_VISIBILITY
1476    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
1477        {return __table_.__equal_range_unique(__k);}
1478#if _LIBCPP_STD_VER > 17
1479    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1480    _LIBCPP_INLINE_VISIBILITY
1481    pair<iterator, iterator>             equal_range(const _K2& __k)
1482        {return __table_.__equal_range_unique(__k);}
1483    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1484    _LIBCPP_INLINE_VISIBILITY
1485    pair<const_iterator, const_iterator> equal_range(const _K2& __k) const
1486        {return __table_.__equal_range_unique(__k);}
1487#endif // _LIBCPP_STD_VER > 17
1488
1489    mapped_type& operator[](const key_type& __k);
1490#ifndef _LIBCPP_CXX03_LANG
1491    mapped_type& operator[](key_type&& __k);
1492#endif
1493
1494    mapped_type&       at(const key_type& __k);
1495    const mapped_type& at(const key_type& __k) const;
1496
1497    _LIBCPP_INLINE_VISIBILITY
1498    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
1499    _LIBCPP_INLINE_VISIBILITY
1500    size_type max_bucket_count() const _NOEXCEPT {return __table_.max_bucket_count();}
1501
1502    _LIBCPP_INLINE_VISIBILITY
1503    size_type bucket_size(size_type __n) const
1504        {return __table_.bucket_size(__n);}
1505    _LIBCPP_INLINE_VISIBILITY
1506    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
1507
1508    _LIBCPP_INLINE_VISIBILITY
1509    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
1510    _LIBCPP_INLINE_VISIBILITY
1511    local_iterator       end(size_type __n)          {return __table_.end(__n);}
1512    _LIBCPP_INLINE_VISIBILITY
1513    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
1514    _LIBCPP_INLINE_VISIBILITY
1515    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
1516    _LIBCPP_INLINE_VISIBILITY
1517    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
1518    _LIBCPP_INLINE_VISIBILITY
1519    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
1520
1521    _LIBCPP_INLINE_VISIBILITY
1522    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
1523    _LIBCPP_INLINE_VISIBILITY
1524    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
1525    _LIBCPP_INLINE_VISIBILITY
1526    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
1527    _LIBCPP_INLINE_VISIBILITY
1528    void rehash(size_type __n) {__table_.__rehash_unique(__n);}
1529    _LIBCPP_INLINE_VISIBILITY
1530    void reserve(size_type __n) {__table_.__reserve_unique(__n);}
1531
1532#ifdef _LIBCPP_ENABLE_DEBUG_MODE
1533
1534    bool __dereferenceable(const const_iterator* __i) const
1535        {return __table_.__dereferenceable(_VSTD::addressof(__i->__i_));}
1536    bool __decrementable(const const_iterator* __i) const
1537        {return __table_.__decrementable(_VSTD::addressof(__i->__i_));}
1538    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
1539        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
1540    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
1541        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
1542
1543#endif // _LIBCPP_ENABLE_DEBUG_MODE
1544
1545private:
1546
1547#ifdef _LIBCPP_CXX03_LANG
1548    __node_holder __construct_node_with_key(const key_type& __k);
1549#endif
1550};
1551
1552#if _LIBCPP_STD_VER >= 17
1553template<class _InputIterator,
1554         class _Hash = hash<__iter_key_type<_InputIterator>>,
1555         class _Pred = equal_to<__iter_key_type<_InputIterator>>,
1556         class _Allocator = allocator<__iter_to_alloc_type<_InputIterator>>,
1557         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1558         class = enable_if_t<!__is_allocator<_Hash>::value>,
1559         class = enable_if_t<!is_integral<_Hash>::value>,
1560         class = enable_if_t<!__is_allocator<_Pred>::value>,
1561         class = enable_if_t<__is_allocator<_Allocator>::value>>
1562unordered_map(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
1563              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1564  -> unordered_map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>, _Hash, _Pred, _Allocator>;
1565
1566template<class _Key, class _Tp, class _Hash = hash<remove_const_t<_Key>>,
1567         class _Pred = equal_to<remove_const_t<_Key>>,
1568         class _Allocator = allocator<pair<const _Key, _Tp>>,
1569         class = enable_if_t<!__is_allocator<_Hash>::value>,
1570         class = enable_if_t<!is_integral<_Hash>::value>,
1571         class = enable_if_t<!__is_allocator<_Pred>::value>,
1572         class = enable_if_t<__is_allocator<_Allocator>::value>>
1573unordered_map(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type = 0,
1574              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1575  -> unordered_map<remove_const_t<_Key>, _Tp, _Hash, _Pred, _Allocator>;
1576
1577template<class _InputIterator, class _Allocator,
1578         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1579         class = enable_if_t<__is_allocator<_Allocator>::value>>
1580unordered_map(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
1581  -> unordered_map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
1582                   hash<__iter_key_type<_InputIterator>>, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
1583
1584template<class _InputIterator, class _Allocator,
1585         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1586         class = enable_if_t<__is_allocator<_Allocator>::value>>
1587unordered_map(_InputIterator, _InputIterator, _Allocator)
1588  -> unordered_map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
1589                   hash<__iter_key_type<_InputIterator>>, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
1590
1591template<class _InputIterator, class _Hash, class _Allocator,
1592         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1593         class = enable_if_t<!__is_allocator<_Hash>::value>,
1594         class = enable_if_t<!is_integral<_Hash>::value>,
1595         class = enable_if_t<__is_allocator<_Allocator>::value>>
1596unordered_map(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
1597  -> unordered_map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
1598                   _Hash, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
1599
1600template<class _Key, class _Tp, class _Allocator,
1601         class = enable_if_t<__is_allocator<_Allocator>::value>>
1602unordered_map(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Allocator)
1603  -> unordered_map<remove_const_t<_Key>, _Tp,
1604                   hash<remove_const_t<_Key>>,
1605                   equal_to<remove_const_t<_Key>>, _Allocator>;
1606
1607template<class _Key, class _Tp, class _Allocator,
1608         class = enable_if_t<__is_allocator<_Allocator>::value>>
1609unordered_map(initializer_list<pair<_Key, _Tp>>, _Allocator)
1610  -> unordered_map<remove_const_t<_Key>, _Tp,
1611                   hash<remove_const_t<_Key>>,
1612                   equal_to<remove_const_t<_Key>>, _Allocator>;
1613
1614template<class _Key, class _Tp, class _Hash, class _Allocator,
1615         class = enable_if_t<!__is_allocator<_Hash>::value>,
1616         class = enable_if_t<!is_integral<_Hash>::value>,
1617         class = enable_if_t<__is_allocator<_Allocator>::value>>
1618unordered_map(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
1619  -> unordered_map<remove_const_t<_Key>, _Tp, _Hash,
1620                   equal_to<remove_const_t<_Key>>, _Allocator>;
1621#endif
1622
1623template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1624unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1625        size_type __n, const hasher& __hf, const key_equal& __eql)
1626    : __table_(__hf, __eql)
1627{
1628    _VSTD::__debug_db_insert_c(this);
1629    __table_.__rehash_unique(__n);
1630}
1631
1632template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1633unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1634        size_type __n, const hasher& __hf, const key_equal& __eql,
1635        const allocator_type& __a)
1636    : __table_(__hf, __eql, typename __table::allocator_type(__a))
1637{
1638    _VSTD::__debug_db_insert_c(this);
1639    __table_.__rehash_unique(__n);
1640}
1641
1642template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1643inline
1644unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1645        const allocator_type& __a)
1646    : __table_(typename __table::allocator_type(__a))
1647{
1648    _VSTD::__debug_db_insert_c(this);
1649}
1650
1651template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1652template <class _InputIterator>
1653unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1654        _InputIterator __first, _InputIterator __last)
1655{
1656    _VSTD::__debug_db_insert_c(this);
1657    insert(__first, __last);
1658}
1659
1660template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1661template <class _InputIterator>
1662unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1663        _InputIterator __first, _InputIterator __last, size_type __n,
1664        const hasher& __hf, const key_equal& __eql)
1665    : __table_(__hf, __eql)
1666{
1667    _VSTD::__debug_db_insert_c(this);
1668    __table_.__rehash_unique(__n);
1669    insert(__first, __last);
1670}
1671
1672template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1673template <class _InputIterator>
1674unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1675        _InputIterator __first, _InputIterator __last, size_type __n,
1676        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
1677    : __table_(__hf, __eql, typename __table::allocator_type(__a))
1678{
1679    _VSTD::__debug_db_insert_c(this);
1680    __table_.__rehash_unique(__n);
1681    insert(__first, __last);
1682}
1683
1684template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1685unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1686        const unordered_map& __u)
1687    : __table_(__u.__table_)
1688{
1689    _VSTD::__debug_db_insert_c(this);
1690    __table_.__rehash_unique(__u.bucket_count());
1691    insert(__u.begin(), __u.end());
1692}
1693
1694template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1695unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1696        const unordered_map& __u, const allocator_type& __a)
1697    : __table_(__u.__table_, typename __table::allocator_type(__a))
1698{
1699    _VSTD::__debug_db_insert_c(this);
1700    __table_.__rehash_unique(__u.bucket_count());
1701    insert(__u.begin(), __u.end());
1702}
1703
1704#ifndef _LIBCPP_CXX03_LANG
1705
1706template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1707inline
1708unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1709        unordered_map&& __u)
1710    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
1711    : __table_(_VSTD::move(__u.__table_))
1712{
1713    _VSTD::__debug_db_insert_c(this);
1714    std::__debug_db_swap(this, std::addressof(__u));
1715}
1716
1717template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1718unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1719        unordered_map&& __u, const allocator_type& __a)
1720    : __table_(_VSTD::move(__u.__table_), typename __table::allocator_type(__a))
1721{
1722    _VSTD::__debug_db_insert_c(this);
1723    if (__a != __u.get_allocator())
1724    {
1725        iterator __i = __u.begin();
1726        while (__u.size() != 0) {
1727            __table_.__emplace_unique(
1728                __u.__table_.remove((__i++).__i_)->__value_.__move());
1729        }
1730    }
1731    else
1732        std::__debug_db_swap(this, std::addressof(__u));
1733}
1734
1735template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1736unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1737        initializer_list<value_type> __il)
1738{
1739    _VSTD::__debug_db_insert_c(this);
1740    insert(__il.begin(), __il.end());
1741}
1742
1743template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1744unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1745        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1746        const key_equal& __eql)
1747    : __table_(__hf, __eql)
1748{
1749    _VSTD::__debug_db_insert_c(this);
1750    __table_.__rehash_unique(__n);
1751    insert(__il.begin(), __il.end());
1752}
1753
1754template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1755unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1756        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1757        const key_equal& __eql, const allocator_type& __a)
1758    : __table_(__hf, __eql, typename __table::allocator_type(__a))
1759{
1760    _VSTD::__debug_db_insert_c(this);
1761    __table_.__rehash_unique(__n);
1762    insert(__il.begin(), __il.end());
1763}
1764
1765template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1766inline
1767unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>&
1768unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(unordered_map&& __u)
1769    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
1770{
1771    __table_ = _VSTD::move(__u.__table_);
1772    return *this;
1773}
1774
1775template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1776inline
1777unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>&
1778unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(
1779        initializer_list<value_type> __il)
1780{
1781    __table_.__assign_unique(__il.begin(), __il.end());
1782    return *this;
1783}
1784
1785#endif // _LIBCPP_CXX03_LANG
1786
1787template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1788template <class _InputIterator>
1789inline
1790void
1791unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
1792                                                       _InputIterator __last)
1793{
1794    for (; __first != __last; ++__first)
1795        __table_.__insert_unique(*__first);
1796}
1797
1798#ifndef _LIBCPP_CXX03_LANG
1799
1800template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1801_Tp&
1802unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](const key_type& __k)
1803{
1804    return __table_.__emplace_unique_key_args(__k,
1805        piecewise_construct, _VSTD::forward_as_tuple(__k),
1806                             _VSTD::forward_as_tuple()).first->__get_value().second;
1807}
1808
1809template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1810_Tp&
1811unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](key_type&& __k)
1812{
1813    return __table_.__emplace_unique_key_args(__k,
1814        piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__k)),
1815                             _VSTD::forward_as_tuple()).first->__get_value().second;
1816}
1817#else // _LIBCPP_CXX03_LANG
1818
1819template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1820typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
1821unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node_with_key(const key_type& __k)
1822{
1823    __node_allocator& __na = __table_.__node_alloc();
1824    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
1825    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__get_value().first), __k);
1826    __h.get_deleter().__first_constructed = true;
1827    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__get_value().second));
1828    __h.get_deleter().__second_constructed = true;
1829    return __h;
1830}
1831
1832template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1833_Tp&
1834unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](const key_type& __k)
1835{
1836    iterator __i = find(__k);
1837    if (__i != end())
1838        return __i->second;
1839    __node_holder __h = __construct_node_with_key(__k);
1840    pair<iterator, bool> __r = __table_.__node_insert_unique(__h.get());
1841    __h.release();
1842    return __r.first->second;
1843}
1844
1845#endif // _LIBCPP_CXX03_LANG
1846
1847template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1848_Tp&
1849unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::at(const key_type& __k)
1850{
1851    iterator __i = find(__k);
1852    if (__i == end())
1853        __throw_out_of_range("unordered_map::at: key not found");
1854    return __i->second;
1855}
1856
1857template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1858const _Tp&
1859unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::at(const key_type& __k) const
1860{
1861    const_iterator __i = find(__k);
1862    if (__i == end())
1863        __throw_out_of_range("unordered_map::at: key not found");
1864    return __i->second;
1865}
1866
1867template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1868inline _LIBCPP_INLINE_VISIBILITY
1869void
1870swap(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
1871     unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
1872    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1873{
1874    __x.swap(__y);
1875}
1876
1877#if _LIBCPP_STD_VER > 17
1878template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc,
1879          class _Predicate>
1880inline _LIBCPP_INLINE_VISIBILITY
1881    typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::size_type
1882    erase_if(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __c,
1883             _Predicate __pred) {
1884  return _VSTD::__libcpp_erase_if_container(__c, __pred);
1885}
1886#endif
1887
1888template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1889_LIBCPP_HIDE_FROM_ABI bool
1890operator==(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
1891           const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
1892{
1893    if (__x.size() != __y.size())
1894        return false;
1895    typedef typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator
1896                                                                 const_iterator;
1897    for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end();
1898            __i != __ex; ++__i)
1899    {
1900        const_iterator __j = __y.find(__i->first);
1901        if (__j == __ey || !(*__i == *__j))
1902            return false;
1903    }
1904    return true;
1905}
1906
1907template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1908inline _LIBCPP_INLINE_VISIBILITY
1909bool
1910operator!=(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
1911           const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
1912{
1913    return !(__x == __y);
1914}
1915
1916template <class _Key, class _Tp, class _Hash = hash<_Key>, class _Pred = equal_to<_Key>,
1917          class _Alloc = allocator<pair<const _Key, _Tp> > >
1918class _LIBCPP_TEMPLATE_VIS unordered_multimap
1919{
1920public:
1921    // types
1922    typedef _Key                                           key_type;
1923    typedef _Tp                                            mapped_type;
1924    typedef __type_identity_t<_Hash>                       hasher;
1925    typedef __type_identity_t<_Pred>                       key_equal;
1926    typedef __type_identity_t<_Alloc>                      allocator_type;
1927    typedef pair<const key_type, mapped_type>              value_type;
1928    typedef value_type&                                    reference;
1929    typedef const value_type&                              const_reference;
1930    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
1931                  "Invalid allocator::value_type");
1932
1933private:
1934    typedef __hash_value_type<key_type, mapped_type>                          __value_type;
1935    typedef __unordered_map_hasher<key_type, __value_type, hasher, key_equal> __hasher;
1936    typedef __unordered_map_equal<key_type, __value_type, key_equal, hasher>  __key_equal;
1937    typedef __rebind_alloc<allocator_traits<allocator_type>, __value_type>    __allocator_type;
1938
1939    typedef __hash_table<__value_type, __hasher,
1940                         __key_equal,  __allocator_type>   __table;
1941
1942    __table __table_;
1943
1944    typedef typename __table::_NodeTypes                   _NodeTypes;
1945    typedef typename __table::__node_traits                __node_traits;
1946    typedef typename __table::__node_allocator             __node_allocator;
1947    typedef typename __table::__node                       __node;
1948    typedef __hash_map_node_destructor<__node_allocator>   _Dp;
1949    typedef unique_ptr<__node, _Dp>                         __node_holder;
1950    typedef allocator_traits<allocator_type>               __alloc_traits;
1951    static_assert((is_same<typename __node_traits::size_type,
1952                          typename __alloc_traits::size_type>::value),
1953                 "Allocator uses different size_type for different types");
1954
1955    static_assert(is_same<allocator_type, __rebind_alloc<__alloc_traits, value_type> >::value,
1956                  "[allocator.requirements] states that rebinding an allocator to the same type should result in the "
1957                  "original allocator");
1958
1959  public:
1960    typedef typename __alloc_traits::pointer         pointer;
1961    typedef typename __alloc_traits::const_pointer   const_pointer;
1962    typedef typename __table::size_type              size_type;
1963    typedef typename __table::difference_type        difference_type;
1964
1965    typedef __hash_map_iterator<typename __table::iterator>       iterator;
1966    typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
1967    typedef __hash_map_iterator<typename __table::local_iterator> local_iterator;
1968    typedef __hash_map_const_iterator<typename __table::const_local_iterator> const_local_iterator;
1969
1970#if _LIBCPP_STD_VER > 14
1971    typedef __map_node_handle<__node, allocator_type> node_type;
1972#endif
1973
1974    template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
1975        friend class _LIBCPP_TEMPLATE_VIS unordered_map;
1976    template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
1977        friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
1978
1979    _LIBCPP_INLINE_VISIBILITY
1980    unordered_multimap()
1981        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
1982    {
1983        _VSTD::__debug_db_insert_c(this);
1984    }
1985    explicit unordered_multimap(size_type __n, const hasher& __hf = hasher(),
1986                                const key_equal& __eql = key_equal());
1987    unordered_multimap(size_type __n, const hasher& __hf,
1988                                const key_equal& __eql,
1989                                const allocator_type& __a);
1990    template <class _InputIterator>
1991        unordered_multimap(_InputIterator __first, _InputIterator __last);
1992    template <class _InputIterator>
1993        unordered_multimap(_InputIterator __first, _InputIterator __last,
1994                      size_type __n, const hasher& __hf = hasher(),
1995                      const key_equal& __eql = key_equal());
1996    template <class _InputIterator>
1997        unordered_multimap(_InputIterator __first, _InputIterator __last,
1998                      size_type __n, const hasher& __hf,
1999                      const key_equal& __eql,
2000                      const allocator_type& __a);
2001    _LIBCPP_INLINE_VISIBILITY
2002    explicit unordered_multimap(const allocator_type& __a);
2003    unordered_multimap(const unordered_multimap& __u);
2004    unordered_multimap(const unordered_multimap& __u, const allocator_type& __a);
2005#ifndef _LIBCPP_CXX03_LANG
2006    _LIBCPP_INLINE_VISIBILITY
2007    unordered_multimap(unordered_multimap&& __u)
2008        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
2009    unordered_multimap(unordered_multimap&& __u, const allocator_type& __a);
2010    unordered_multimap(initializer_list<value_type> __il);
2011    unordered_multimap(initializer_list<value_type> __il, size_type __n,
2012                       const hasher& __hf = hasher(),
2013                       const key_equal& __eql = key_equal());
2014    unordered_multimap(initializer_list<value_type> __il, size_type __n,
2015                       const hasher& __hf, const key_equal& __eql,
2016                       const allocator_type& __a);
2017#endif // _LIBCPP_CXX03_LANG
2018#if _LIBCPP_STD_VER > 11
2019    _LIBCPP_INLINE_VISIBILITY
2020    unordered_multimap(size_type __n, const allocator_type& __a)
2021      : unordered_multimap(__n, hasher(), key_equal(), __a) {}
2022    _LIBCPP_INLINE_VISIBILITY
2023    unordered_multimap(size_type __n, const hasher& __hf, const allocator_type& __a)
2024      : unordered_multimap(__n, __hf, key_equal(), __a) {}
2025    template <class _InputIterator>
2026    _LIBCPP_INLINE_VISIBILITY
2027      unordered_multimap(_InputIterator __first, _InputIterator __last, size_type __n, const allocator_type& __a)
2028      : unordered_multimap(__first, __last, __n, hasher(), key_equal(), __a) {}
2029    template <class _InputIterator>
2030    _LIBCPP_INLINE_VISIBILITY
2031      unordered_multimap(_InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf,
2032        const allocator_type& __a)
2033      : unordered_multimap(__first, __last, __n, __hf, key_equal(), __a) {}
2034    _LIBCPP_INLINE_VISIBILITY
2035    unordered_multimap(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
2036      : unordered_multimap(__il, __n, hasher(), key_equal(), __a) {}
2037    _LIBCPP_INLINE_VISIBILITY
2038    unordered_multimap(initializer_list<value_type> __il, size_type __n, const hasher& __hf,
2039      const allocator_type& __a)
2040      : unordered_multimap(__il, __n, __hf, key_equal(), __a) {}
2041#endif
2042    _LIBCPP_INLINE_VISIBILITY
2043    ~unordered_multimap() {
2044        static_assert(sizeof(std::__diagnose_unordered_container_requirements<_Key, _Hash, _Pred>(0)), "");
2045    }
2046
2047    _LIBCPP_INLINE_VISIBILITY
2048    unordered_multimap& operator=(const unordered_multimap& __u)
2049    {
2050#ifndef _LIBCPP_CXX03_LANG
2051        __table_ = __u.__table_;
2052#else
2053        if (this != _VSTD::addressof(__u)) {
2054            __table_.clear();
2055            __table_.hash_function() = __u.__table_.hash_function();
2056            __table_.key_eq() = __u.__table_.key_eq();
2057            __table_.max_load_factor() = __u.__table_.max_load_factor();
2058            __table_.__copy_assign_alloc(__u.__table_);
2059            insert(__u.begin(), __u.end());
2060        }
2061#endif
2062        return *this;
2063    }
2064#ifndef _LIBCPP_CXX03_LANG
2065    _LIBCPP_INLINE_VISIBILITY
2066    unordered_multimap& operator=(unordered_multimap&& __u)
2067        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
2068    _LIBCPP_INLINE_VISIBILITY
2069    unordered_multimap& operator=(initializer_list<value_type> __il);
2070#endif // _LIBCPP_CXX03_LANG
2071
2072    _LIBCPP_INLINE_VISIBILITY
2073    allocator_type get_allocator() const _NOEXCEPT
2074        {return allocator_type(__table_.__node_alloc());}
2075
2076    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
2077    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
2078    _LIBCPP_INLINE_VISIBILITY
2079    size_type size() const _NOEXCEPT  {return __table_.size();}
2080    _LIBCPP_INLINE_VISIBILITY
2081    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
2082
2083    _LIBCPP_INLINE_VISIBILITY
2084    iterator       begin() _NOEXCEPT        {return __table_.begin();}
2085    _LIBCPP_INLINE_VISIBILITY
2086    iterator       end() _NOEXCEPT          {return __table_.end();}
2087    _LIBCPP_INLINE_VISIBILITY
2088    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
2089    _LIBCPP_INLINE_VISIBILITY
2090    const_iterator end()    const _NOEXCEPT {return __table_.end();}
2091    _LIBCPP_INLINE_VISIBILITY
2092    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
2093    _LIBCPP_INLINE_VISIBILITY
2094    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
2095
2096    _LIBCPP_INLINE_VISIBILITY
2097    iterator insert(const value_type& __x) {return __table_.__insert_multi(__x);}
2098
2099    _LIBCPP_INLINE_VISIBILITY
2100    iterator insert(const_iterator __p, const value_type& __x)
2101        {return __table_.__insert_multi(__p.__i_, __x);}
2102
2103    template <class _InputIterator>
2104    _LIBCPP_INLINE_VISIBILITY
2105    void insert(_InputIterator __first, _InputIterator __last);
2106
2107#ifndef _LIBCPP_CXX03_LANG
2108    _LIBCPP_INLINE_VISIBILITY
2109    void insert(initializer_list<value_type> __il)
2110        {insert(__il.begin(), __il.end());}
2111    _LIBCPP_INLINE_VISIBILITY
2112    iterator insert(value_type&& __x) {return __table_.__insert_multi(_VSTD::move(__x));}
2113
2114    _LIBCPP_INLINE_VISIBILITY
2115    iterator insert(const_iterator __p, value_type&& __x)
2116        {return __table_.__insert_multi(__p.__i_, _VSTD::move(__x));}
2117
2118    template <class _Pp,
2119              class = __enable_if_t<is_constructible<value_type, _Pp>::value> >
2120    _LIBCPP_INLINE_VISIBILITY
2121    iterator insert(_Pp&& __x)
2122        {return __table_.__insert_multi(_VSTD::forward<_Pp>(__x));}
2123
2124    template <class _Pp,
2125              class = __enable_if_t<is_constructible<value_type, _Pp>::value> >
2126    _LIBCPP_INLINE_VISIBILITY
2127    iterator insert(const_iterator __p, _Pp&& __x)
2128        {return __table_.__insert_multi(__p.__i_, _VSTD::forward<_Pp>(__x));}
2129
2130    template <class... _Args>
2131    iterator emplace(_Args&&... __args) {
2132        return __table_.__emplace_multi(_VSTD::forward<_Args>(__args)...);
2133    }
2134
2135    template <class... _Args>
2136    iterator emplace_hint(const_iterator __p, _Args&&... __args) {
2137        return __table_.__emplace_hint_multi(__p.__i_, _VSTD::forward<_Args>(__args)...);
2138    }
2139#endif // _LIBCPP_CXX03_LANG
2140
2141
2142    _LIBCPP_INLINE_VISIBILITY
2143    iterator erase(const_iterator __p) {return __table_.erase(__p.__i_);}
2144    _LIBCPP_INLINE_VISIBILITY
2145    iterator erase(iterator __p)       {return __table_.erase(__p.__i_);}
2146    _LIBCPP_INLINE_VISIBILITY
2147    size_type erase(const key_type& __k) {return __table_.__erase_multi(__k);}
2148    _LIBCPP_INLINE_VISIBILITY
2149    iterator erase(const_iterator __first, const_iterator __last)
2150        {return __table_.erase(__first.__i_, __last.__i_);}
2151    _LIBCPP_INLINE_VISIBILITY
2152    void clear() _NOEXCEPT {__table_.clear();}
2153
2154#if _LIBCPP_STD_VER > 14
2155    _LIBCPP_INLINE_VISIBILITY
2156    iterator insert(node_type&& __nh)
2157    {
2158        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
2159            "node_type with incompatible allocator passed to unordered_multimap::insert()");
2160        return __table_.template __node_handle_insert_multi<node_type>(
2161            _VSTD::move(__nh));
2162    }
2163    _LIBCPP_INLINE_VISIBILITY
2164    iterator insert(const_iterator __hint, node_type&& __nh)
2165    {
2166        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
2167            "node_type with incompatible allocator passed to unordered_multimap::insert()");
2168        return __table_.template __node_handle_insert_multi<node_type>(
2169            __hint.__i_, _VSTD::move(__nh));
2170    }
2171    _LIBCPP_INLINE_VISIBILITY
2172    node_type extract(key_type const& __key)
2173    {
2174        return __table_.template __node_handle_extract<node_type>(__key);
2175    }
2176    _LIBCPP_INLINE_VISIBILITY
2177    node_type extract(const_iterator __it)
2178    {
2179        return __table_.template __node_handle_extract<node_type>(
2180            __it.__i_);
2181    }
2182
2183    template <class _H2, class _P2>
2184    _LIBCPP_INLINE_VISIBILITY
2185    void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>& __source)
2186    {
2187        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
2188                       "merging container with incompatible allocator");
2189        return __table_.__node_handle_merge_multi(__source.__table_);
2190    }
2191    template <class _H2, class _P2>
2192    _LIBCPP_INLINE_VISIBILITY
2193    void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>&& __source)
2194    {
2195        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
2196                       "merging container with incompatible allocator");
2197        return __table_.__node_handle_merge_multi(__source.__table_);
2198    }
2199    template <class _H2, class _P2>
2200    _LIBCPP_INLINE_VISIBILITY
2201    void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>& __source)
2202    {
2203        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
2204                       "merging container with incompatible allocator");
2205        return __table_.__node_handle_merge_multi(__source.__table_);
2206    }
2207    template <class _H2, class _P2>
2208    _LIBCPP_INLINE_VISIBILITY
2209    void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>&& __source)
2210    {
2211        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
2212                       "merging container with incompatible allocator");
2213        return __table_.__node_handle_merge_multi(__source.__table_);
2214    }
2215#endif
2216
2217    _LIBCPP_INLINE_VISIBILITY
2218    void swap(unordered_multimap& __u)
2219        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
2220        {__table_.swap(__u.__table_);}
2221
2222    _LIBCPP_INLINE_VISIBILITY
2223    hasher hash_function() const
2224        {return __table_.hash_function().hash_function();}
2225    _LIBCPP_INLINE_VISIBILITY
2226    key_equal key_eq() const
2227        {return __table_.key_eq().key_eq();}
2228
2229    _LIBCPP_INLINE_VISIBILITY
2230    iterator       find(const key_type& __k)       {return __table_.find(__k);}
2231    _LIBCPP_INLINE_VISIBILITY
2232    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
2233#if _LIBCPP_STD_VER > 17
2234    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2235    _LIBCPP_INLINE_VISIBILITY
2236    iterator       find(const _K2& __k)            {return __table_.find(__k);}
2237    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2238    _LIBCPP_INLINE_VISIBILITY
2239    const_iterator find(const _K2& __k) const      {return __table_.find(__k);}
2240#endif // _LIBCPP_STD_VER > 17
2241
2242    _LIBCPP_INLINE_VISIBILITY
2243    size_type count(const key_type& __k) const {return __table_.__count_multi(__k);}
2244#if _LIBCPP_STD_VER > 17
2245    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2246    _LIBCPP_INLINE_VISIBILITY
2247    size_type count(const _K2& __k) const      {return __table_.__count_multi(__k);}
2248#endif // _LIBCPP_STD_VER > 17
2249
2250#if _LIBCPP_STD_VER > 17
2251    _LIBCPP_INLINE_VISIBILITY
2252    bool contains(const key_type& __k) const {return find(__k) != end();}
2253
2254    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2255    _LIBCPP_INLINE_VISIBILITY
2256    bool contains(const _K2& __k) const      {return find(__k) != end();}
2257#endif // _LIBCPP_STD_VER > 17
2258
2259    _LIBCPP_INLINE_VISIBILITY
2260    pair<iterator, iterator>             equal_range(const key_type& __k)
2261        {return __table_.__equal_range_multi(__k);}
2262    _LIBCPP_INLINE_VISIBILITY
2263    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
2264        {return __table_.__equal_range_multi(__k);}
2265#if _LIBCPP_STD_VER > 17
2266    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2267    _LIBCPP_INLINE_VISIBILITY
2268    pair<iterator, iterator>             equal_range(const _K2& __k)
2269        {return __table_.__equal_range_multi(__k);}
2270    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2271    _LIBCPP_INLINE_VISIBILITY
2272    pair<const_iterator, const_iterator> equal_range(const _K2& __k) const
2273        {return __table_.__equal_range_multi(__k);}
2274#endif // _LIBCPP_STD_VER > 17
2275
2276    _LIBCPP_INLINE_VISIBILITY
2277    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
2278    _LIBCPP_INLINE_VISIBILITY
2279    size_type max_bucket_count() const _NOEXCEPT
2280        {return __table_.max_bucket_count();}
2281
2282    _LIBCPP_INLINE_VISIBILITY
2283    size_type bucket_size(size_type __n) const
2284        {return __table_.bucket_size(__n);}
2285    _LIBCPP_INLINE_VISIBILITY
2286    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
2287
2288    _LIBCPP_INLINE_VISIBILITY
2289    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
2290    _LIBCPP_INLINE_VISIBILITY
2291    local_iterator       end(size_type __n)          {return __table_.end(__n);}
2292    _LIBCPP_INLINE_VISIBILITY
2293    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
2294    _LIBCPP_INLINE_VISIBILITY
2295    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
2296    _LIBCPP_INLINE_VISIBILITY
2297    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
2298    _LIBCPP_INLINE_VISIBILITY
2299    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
2300
2301    _LIBCPP_INLINE_VISIBILITY
2302    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
2303    _LIBCPP_INLINE_VISIBILITY
2304    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
2305    _LIBCPP_INLINE_VISIBILITY
2306    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
2307    _LIBCPP_INLINE_VISIBILITY
2308    void rehash(size_type __n) {__table_.__rehash_multi(__n);}
2309    _LIBCPP_INLINE_VISIBILITY
2310    void reserve(size_type __n) {__table_.__reserve_multi(__n);}
2311
2312#ifdef _LIBCPP_ENABLE_DEBUG_MODE
2313
2314    bool __dereferenceable(const const_iterator* __i) const
2315        {return __table_.__dereferenceable(_VSTD::addressof(__i->__i_));}
2316    bool __decrementable(const const_iterator* __i) const
2317        {return __table_.__decrementable(_VSTD::addressof(__i->__i_));}
2318    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
2319        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
2320    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
2321        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
2322
2323#endif // _LIBCPP_ENABLE_DEBUG_MODE
2324
2325
2326};
2327
2328#if _LIBCPP_STD_VER >= 17
2329template<class _InputIterator,
2330         class _Hash = hash<__iter_key_type<_InputIterator>>,
2331         class _Pred = equal_to<__iter_key_type<_InputIterator>>,
2332         class _Allocator = allocator<__iter_to_alloc_type<_InputIterator>>,
2333         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
2334         class = enable_if_t<!__is_allocator<_Hash>::value>,
2335         class = enable_if_t<!is_integral<_Hash>::value>,
2336         class = enable_if_t<!__is_allocator<_Pred>::value>,
2337         class = enable_if_t<__is_allocator<_Allocator>::value>>
2338unordered_multimap(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
2339                   _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
2340  -> unordered_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>, _Hash, _Pred, _Allocator>;
2341
2342template<class _Key, class _Tp, class _Hash = hash<remove_const_t<_Key>>,
2343         class _Pred = equal_to<remove_const_t<_Key>>,
2344         class _Allocator = allocator<pair<const _Key, _Tp>>,
2345         class = enable_if_t<!__is_allocator<_Hash>::value>,
2346         class = enable_if_t<!is_integral<_Hash>::value>,
2347         class = enable_if_t<!__is_allocator<_Pred>::value>,
2348         class = enable_if_t<__is_allocator<_Allocator>::value>>
2349unordered_multimap(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type = 0,
2350                   _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
2351  -> unordered_multimap<remove_const_t<_Key>, _Tp, _Hash, _Pred, _Allocator>;
2352
2353template<class _InputIterator, class _Allocator,
2354         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
2355         class = enable_if_t<__is_allocator<_Allocator>::value>>
2356unordered_multimap(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
2357  -> unordered_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
2358                        hash<__iter_key_type<_InputIterator>>, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
2359
2360template<class _InputIterator, class _Allocator,
2361         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
2362         class = enable_if_t<__is_allocator<_Allocator>::value>>
2363unordered_multimap(_InputIterator, _InputIterator, _Allocator)
2364  -> unordered_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
2365                        hash<__iter_key_type<_InputIterator>>, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
2366
2367template<class _InputIterator, class _Hash, class _Allocator,
2368         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
2369         class = enable_if_t<!__is_allocator<_Hash>::value>,
2370         class = enable_if_t<!is_integral<_Hash>::value>,
2371         class = enable_if_t<__is_allocator<_Allocator>::value>>
2372unordered_multimap(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
2373  -> unordered_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
2374                        _Hash, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
2375
2376template<class _Key, class _Tp, class _Allocator,
2377         class = enable_if_t<__is_allocator<_Allocator>::value>>
2378unordered_multimap(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Allocator)
2379  -> unordered_multimap<remove_const_t<_Key>, _Tp,
2380                        hash<remove_const_t<_Key>>,
2381                        equal_to<remove_const_t<_Key>>, _Allocator>;
2382
2383template<class _Key, class _Tp, class _Allocator,
2384         class = enable_if_t<__is_allocator<_Allocator>::value>>
2385unordered_multimap(initializer_list<pair<_Key, _Tp>>, _Allocator)
2386  -> unordered_multimap<remove_const_t<_Key>, _Tp,
2387                        hash<remove_const_t<_Key>>,
2388                        equal_to<remove_const_t<_Key>>, _Allocator>;
2389
2390template<class _Key, class _Tp, class _Hash, class _Allocator,
2391         class = enable_if_t<!__is_allocator<_Hash>::value>,
2392         class = enable_if_t<!is_integral<_Hash>::value>,
2393         class = enable_if_t<__is_allocator<_Allocator>::value>>
2394unordered_multimap(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
2395  -> unordered_multimap<remove_const_t<_Key>, _Tp, _Hash,
2396                        equal_to<remove_const_t<_Key>>, _Allocator>;
2397#endif
2398
2399template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2400unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2401        size_type __n, const hasher& __hf, const key_equal& __eql)
2402    : __table_(__hf, __eql)
2403{
2404    _VSTD::__debug_db_insert_c(this);
2405    __table_.__rehash_multi(__n);
2406}
2407
2408template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2409unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2410        size_type __n, const hasher& __hf, const key_equal& __eql,
2411        const allocator_type& __a)
2412    : __table_(__hf, __eql, typename __table::allocator_type(__a))
2413{
2414    _VSTD::__debug_db_insert_c(this);
2415    __table_.__rehash_multi(__n);
2416}
2417
2418template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2419template <class _InputIterator>
2420unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2421        _InputIterator __first, _InputIterator __last)
2422{
2423    _VSTD::__debug_db_insert_c(this);
2424    insert(__first, __last);
2425}
2426
2427template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2428template <class _InputIterator>
2429unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2430        _InputIterator __first, _InputIterator __last, size_type __n,
2431        const hasher& __hf, const key_equal& __eql)
2432    : __table_(__hf, __eql)
2433{
2434    _VSTD::__debug_db_insert_c(this);
2435    __table_.__rehash_multi(__n);
2436    insert(__first, __last);
2437}
2438
2439template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2440template <class _InputIterator>
2441unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2442        _InputIterator __first, _InputIterator __last, size_type __n,
2443        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
2444    : __table_(__hf, __eql, typename __table::allocator_type(__a))
2445{
2446    _VSTD::__debug_db_insert_c(this);
2447    __table_.__rehash_multi(__n);
2448    insert(__first, __last);
2449}
2450
2451template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2452inline
2453unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2454        const allocator_type& __a)
2455    : __table_(typename __table::allocator_type(__a))
2456{
2457    _VSTD::__debug_db_insert_c(this);
2458}
2459
2460template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2461unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2462        const unordered_multimap& __u)
2463    : __table_(__u.__table_)
2464{
2465    _VSTD::__debug_db_insert_c(this);
2466    __table_.__rehash_multi(__u.bucket_count());
2467    insert(__u.begin(), __u.end());
2468}
2469
2470template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2471unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2472        const unordered_multimap& __u, const allocator_type& __a)
2473    : __table_(__u.__table_, typename __table::allocator_type(__a))
2474{
2475    _VSTD::__debug_db_insert_c(this);
2476    __table_.__rehash_multi(__u.bucket_count());
2477    insert(__u.begin(), __u.end());
2478}
2479
2480#ifndef _LIBCPP_CXX03_LANG
2481
2482template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2483inline
2484unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2485        unordered_multimap&& __u)
2486    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
2487    : __table_(_VSTD::move(__u.__table_))
2488{
2489    _VSTD::__debug_db_insert_c(this);
2490    std::__debug_db_swap(this, std::addressof(__u));
2491}
2492
2493template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2494unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2495        unordered_multimap&& __u, const allocator_type& __a)
2496    : __table_(_VSTD::move(__u.__table_), typename __table::allocator_type(__a))
2497{
2498    _VSTD::__debug_db_insert_c(this);
2499    if (__a != __u.get_allocator())
2500    {
2501        iterator __i = __u.begin();
2502        while (__u.size() != 0)
2503        {
2504            __table_.__insert_multi(
2505                __u.__table_.remove((__i++).__i_)->__value_.__move());
2506        }
2507    }
2508    else
2509        std::__debug_db_swap(this, std::addressof(__u));
2510}
2511
2512template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2513unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2514        initializer_list<value_type> __il)
2515{
2516    _VSTD::__debug_db_insert_c(this);
2517    insert(__il.begin(), __il.end());
2518}
2519
2520template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2521unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2522        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
2523        const key_equal& __eql)
2524    : __table_(__hf, __eql)
2525{
2526    _VSTD::__debug_db_insert_c(this);
2527    __table_.__rehash_multi(__n);
2528    insert(__il.begin(), __il.end());
2529}
2530
2531template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2532unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2533        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
2534        const key_equal& __eql, const allocator_type& __a)
2535    : __table_(__hf, __eql, typename __table::allocator_type(__a))
2536{
2537    _VSTD::__debug_db_insert_c(this);
2538    __table_.__rehash_multi(__n);
2539    insert(__il.begin(), __il.end());
2540}
2541
2542template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2543inline
2544unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>&
2545unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(unordered_multimap&& __u)
2546    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
2547{
2548    __table_ = _VSTD::move(__u.__table_);
2549    return *this;
2550}
2551
2552template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2553inline
2554unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>&
2555unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(
2556        initializer_list<value_type> __il)
2557{
2558    __table_.__assign_multi(__il.begin(), __il.end());
2559    return *this;
2560}
2561
2562#endif // _LIBCPP_CXX03_LANG
2563
2564
2565
2566template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2567template <class _InputIterator>
2568inline
2569void
2570unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
2571                                                            _InputIterator __last)
2572{
2573    for (; __first != __last; ++__first)
2574        __table_.__insert_multi(*__first);
2575}
2576
2577template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2578inline _LIBCPP_INLINE_VISIBILITY
2579void
2580swap(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
2581     unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
2582    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
2583{
2584    __x.swap(__y);
2585}
2586
2587#if _LIBCPP_STD_VER > 17
2588template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc,
2589          class _Predicate>
2590inline _LIBCPP_INLINE_VISIBILITY
2591    typename unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::size_type
2592    erase_if(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __c,
2593             _Predicate __pred) {
2594  return _VSTD::__libcpp_erase_if_container(__c, __pred);
2595}
2596#endif
2597
2598template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2599_LIBCPP_HIDE_FROM_ABI bool
2600operator==(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
2601           const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
2602{
2603    if (__x.size() != __y.size())
2604        return false;
2605    typedef typename unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator
2606                                                                 const_iterator;
2607    typedef pair<const_iterator, const_iterator> _EqRng;
2608    for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;)
2609    {
2610        _EqRng __xeq = __x.equal_range(__i->first);
2611        _EqRng __yeq = __y.equal_range(__i->first);
2612        if (_VSTD::distance(__xeq.first, __xeq.second) !=
2613            _VSTD::distance(__yeq.first, __yeq.second) ||
2614                  !_VSTD::is_permutation(__xeq.first, __xeq.second, __yeq.first))
2615            return false;
2616        __i = __xeq.second;
2617    }
2618    return true;
2619}
2620
2621template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2622inline _LIBCPP_INLINE_VISIBILITY
2623bool
2624operator!=(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
2625           const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
2626{
2627    return !(__x == __y);
2628}
2629
2630_LIBCPP_END_NAMESPACE_STD
2631
2632#if _LIBCPP_STD_VER > 14
2633_LIBCPP_BEGIN_NAMESPACE_STD
2634namespace pmr {
2635template <class _KeyT, class _ValueT, class _HashT = std::hash<_KeyT>, class _PredT = std::equal_to<_KeyT>>
2636using unordered_map =
2637    std::unordered_map<_KeyT, _ValueT, _HashT, _PredT, polymorphic_allocator<std::pair<const _KeyT, _ValueT>>>;
2638
2639template <class _KeyT, class _ValueT, class _HashT = std::hash<_KeyT>, class _PredT = std::equal_to<_KeyT>>
2640using unordered_multimap =
2641    std::unordered_multimap<_KeyT, _ValueT, _HashT, _PredT, polymorphic_allocator<std::pair<const _KeyT, _ValueT>>>;
2642} // namespace pmr
2643_LIBCPP_END_NAMESPACE_STD
2644#endif
2645
2646#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
2647#  include <algorithm>
2648#  include <bit>
2649#  include <concepts>
2650#  include <iterator>
2651#endif
2652
2653#endif // _LIBCPP_UNORDERED_MAP
2654