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 <__config>
518#include <__debug>
519#include <__functional/is_transparent.h>
520#include <__hash_table>
521#include <__iterator/iterator_traits.h>
522#include <__node_handle>
523#include <__utility/forward.h>
524#include <compare>
525#include <functional>
526#include <iterator> // __libcpp_erase_if_container
527#include <stdexcept>
528#include <tuple>
529#include <version>
530
531#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
532#pragma GCC system_header
533#endif
534
535_LIBCPP_BEGIN_NAMESPACE_STD
536
537template <class _Key, class _Cp, class _Hash, class _Pred,
538          bool = is_empty<_Hash>::value && !__libcpp_is_final<_Hash>::value>
539class __unordered_map_hasher
540    : private _Hash
541{
542public:
543    _LIBCPP_INLINE_VISIBILITY
544    __unordered_map_hasher()
545        _NOEXCEPT_(is_nothrow_default_constructible<_Hash>::value)
546        : _Hash() {}
547    _LIBCPP_INLINE_VISIBILITY
548    __unordered_map_hasher(const _Hash& __h)
549        _NOEXCEPT_(is_nothrow_copy_constructible<_Hash>::value)
550        : _Hash(__h) {}
551    _LIBCPP_INLINE_VISIBILITY
552    const _Hash& hash_function() const _NOEXCEPT {return *this;}
553    _LIBCPP_INLINE_VISIBILITY
554    size_t operator()(const _Cp& __x) const
555        {return static_cast<const _Hash&>(*this)(__x.__get_value().first);}
556    _LIBCPP_INLINE_VISIBILITY
557    size_t operator()(const _Key& __x) const
558        {return static_cast<const _Hash&>(*this)(__x);}
559#if _LIBCPP_STD_VER > 17
560    template <typename _K2>
561    _LIBCPP_INLINE_VISIBILITY
562    size_t operator()(const _K2& __x) const
563        {return static_cast<const _Hash&>(*this)(__x);}
564#endif
565    _LIBCPP_INLINE_VISIBILITY
566    void swap(__unordered_map_hasher& __y)
567        _NOEXCEPT_(__is_nothrow_swappable<_Hash>::value)
568    {
569        using _VSTD::swap;
570        swap(static_cast<_Hash&>(*this), static_cast<_Hash&>(__y));
571    }
572};
573
574template <class _Key, class _Cp, class _Hash, class _Pred>
575class __unordered_map_hasher<_Key, _Cp, _Hash, _Pred, false>
576{
577    _Hash __hash_;
578public:
579    _LIBCPP_INLINE_VISIBILITY
580    __unordered_map_hasher()
581        _NOEXCEPT_(is_nothrow_default_constructible<_Hash>::value)
582        : __hash_() {}
583    _LIBCPP_INLINE_VISIBILITY
584    __unordered_map_hasher(const _Hash& __h)
585        _NOEXCEPT_(is_nothrow_copy_constructible<_Hash>::value)
586        : __hash_(__h) {}
587    _LIBCPP_INLINE_VISIBILITY
588    const _Hash& hash_function() const _NOEXCEPT {return __hash_;}
589    _LIBCPP_INLINE_VISIBILITY
590    size_t operator()(const _Cp& __x) const
591        {return __hash_(__x.__get_value().first);}
592    _LIBCPP_INLINE_VISIBILITY
593    size_t operator()(const _Key& __x) const
594        {return __hash_(__x);}
595#if _LIBCPP_STD_VER > 17
596    template <typename _K2>
597    _LIBCPP_INLINE_VISIBILITY
598    size_t operator()(const _K2& __x) const
599        {return __hash_(__x);}
600#endif
601    _LIBCPP_INLINE_VISIBILITY
602    void swap(__unordered_map_hasher& __y)
603        _NOEXCEPT_(__is_nothrow_swappable<_Hash>::value)
604    {
605        using _VSTD::swap;
606        swap(__hash_, __y.__hash_);
607    }
608};
609
610template <class _Key, class _Cp, class _Hash, class _Pred, bool __b>
611inline _LIBCPP_INLINE_VISIBILITY
612void
613swap(__unordered_map_hasher<_Key, _Cp, _Hash, _Pred, __b>& __x,
614     __unordered_map_hasher<_Key, _Cp, _Hash, _Pred, __b>& __y)
615    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
616{
617    __x.swap(__y);
618}
619
620template <class _Key, class _Cp, class _Pred, class _Hash,
621          bool = is_empty<_Pred>::value && !__libcpp_is_final<_Pred>::value>
622class __unordered_map_equal
623    : private _Pred
624{
625public:
626    _LIBCPP_INLINE_VISIBILITY
627    __unordered_map_equal()
628        _NOEXCEPT_(is_nothrow_default_constructible<_Pred>::value)
629        : _Pred() {}
630    _LIBCPP_INLINE_VISIBILITY
631    __unordered_map_equal(const _Pred& __p)
632        _NOEXCEPT_(is_nothrow_copy_constructible<_Pred>::value)
633        : _Pred(__p) {}
634    _LIBCPP_INLINE_VISIBILITY
635    const _Pred& key_eq() const _NOEXCEPT {return *this;}
636    _LIBCPP_INLINE_VISIBILITY
637    bool operator()(const _Cp& __x, const _Cp& __y) const
638        {return static_cast<const _Pred&>(*this)(__x.__get_value().first, __y.__get_value().first);}
639    _LIBCPP_INLINE_VISIBILITY
640    bool operator()(const _Cp& __x, const _Key& __y) const
641        {return static_cast<const _Pred&>(*this)(__x.__get_value().first, __y);}
642    _LIBCPP_INLINE_VISIBILITY
643    bool operator()(const _Key& __x, const _Cp& __y) const
644        {return static_cast<const _Pred&>(*this)(__x, __y.__get_value().first);}
645#if _LIBCPP_STD_VER > 17
646    template <typename _K2>
647    _LIBCPP_INLINE_VISIBILITY
648    bool operator()(const _Cp& __x, const _K2& __y) const
649        {return static_cast<const _Pred&>(*this)(__x.__get_value().first, __y);}
650    template <typename _K2>
651    _LIBCPP_INLINE_VISIBILITY
652    bool operator()(const _K2& __x, const _Cp& __y) const
653        {return static_cast<const _Pred&>(*this)(__x, __y.__get_value().first);}
654    template <typename _K2>
655    _LIBCPP_INLINE_VISIBILITY
656    bool operator()(const _Key& __x, const _K2& __y) const
657        {return static_cast<const _Pred&>(*this)(__x, __y);}
658    template <typename _K2>
659    _LIBCPP_INLINE_VISIBILITY
660    bool operator()(const _K2& __x, const _Key& __y) const
661        {return static_cast<const _Pred&>(*this)(__x, __y);}
662#endif
663    _LIBCPP_INLINE_VISIBILITY
664    void swap(__unordered_map_equal& __y)
665        _NOEXCEPT_(__is_nothrow_swappable<_Pred>::value)
666    {
667        using _VSTD::swap;
668        swap(static_cast<_Pred&>(*this), static_cast<_Pred&>(__y));
669    }
670};
671
672template <class _Key, class _Cp, class _Pred, class _Hash>
673class __unordered_map_equal<_Key, _Cp, _Pred, _Hash, false>
674{
675    _Pred __pred_;
676public:
677    _LIBCPP_INLINE_VISIBILITY
678    __unordered_map_equal()
679        _NOEXCEPT_(is_nothrow_default_constructible<_Pred>::value)
680        : __pred_() {}
681    _LIBCPP_INLINE_VISIBILITY
682    __unordered_map_equal(const _Pred& __p)
683        _NOEXCEPT_(is_nothrow_copy_constructible<_Pred>::value)
684        : __pred_(__p) {}
685    _LIBCPP_INLINE_VISIBILITY
686    const _Pred& key_eq() const _NOEXCEPT {return __pred_;}
687    _LIBCPP_INLINE_VISIBILITY
688    bool operator()(const _Cp& __x, const _Cp& __y) const
689        {return __pred_(__x.__get_value().first, __y.__get_value().first);}
690    _LIBCPP_INLINE_VISIBILITY
691    bool operator()(const _Cp& __x, const _Key& __y) const
692        {return __pred_(__x.__get_value().first, __y);}
693    _LIBCPP_INLINE_VISIBILITY
694    bool operator()(const _Key& __x, const _Cp& __y) const
695        {return __pred_(__x, __y.__get_value().first);}
696#if _LIBCPP_STD_VER > 17
697    template <typename _K2>
698    _LIBCPP_INLINE_VISIBILITY
699    bool operator()(const _Cp& __x, const _K2& __y) const
700        {return __pred_(__x.__get_value().first, __y);}
701    template <typename _K2>
702    _LIBCPP_INLINE_VISIBILITY
703    bool operator()(const _K2& __x, const _Cp& __y) const
704        {return __pred_(__x, __y.__get_value().first);}
705    template <typename _K2>
706    _LIBCPP_INLINE_VISIBILITY
707    bool operator()(const _Key& __x, const _K2& __y) const
708        {return __pred_(__x, __y);}
709    template <typename _K2>
710    _LIBCPP_INLINE_VISIBILITY
711    bool operator()(const _K2& __x, const _Key& __y) const
712        {return __pred_(__x, __y);}
713#endif
714    _LIBCPP_INLINE_VISIBILITY
715    void swap(__unordered_map_equal& __y)
716        _NOEXCEPT_(__is_nothrow_swappable<_Pred>::value)
717    {
718        using _VSTD::swap;
719        swap(__pred_, __y.__pred_);
720    }
721};
722
723template <class _Key, class _Cp, class _Pred, class _Hash, bool __b>
724inline _LIBCPP_INLINE_VISIBILITY
725void
726swap(__unordered_map_equal<_Key, _Cp, _Pred, _Hash, __b>& __x,
727     __unordered_map_equal<_Key, _Cp, _Pred, _Hash, __b>& __y)
728    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
729{
730    __x.swap(__y);
731}
732
733template <class _Alloc>
734class __hash_map_node_destructor
735{
736    typedef _Alloc                              allocator_type;
737    typedef allocator_traits<allocator_type>    __alloc_traits;
738
739public:
740
741    typedef typename __alloc_traits::pointer       pointer;
742private:
743
744    allocator_type& __na_;
745
746    __hash_map_node_destructor& operator=(const __hash_map_node_destructor&);
747
748public:
749    bool __first_constructed;
750    bool __second_constructed;
751
752    _LIBCPP_INLINE_VISIBILITY
753    explicit __hash_map_node_destructor(allocator_type& __na) _NOEXCEPT
754        : __na_(__na),
755          __first_constructed(false),
756          __second_constructed(false)
757        {}
758
759#ifndef _LIBCPP_CXX03_LANG
760    _LIBCPP_INLINE_VISIBILITY
761    __hash_map_node_destructor(__hash_node_destructor<allocator_type>&& __x)
762        _NOEXCEPT
763        : __na_(__x.__na_),
764          __first_constructed(__x.__value_constructed),
765          __second_constructed(__x.__value_constructed)
766        {
767            __x.__value_constructed = false;
768        }
769#else  // _LIBCPP_CXX03_LANG
770    _LIBCPP_INLINE_VISIBILITY
771    __hash_map_node_destructor(const __hash_node_destructor<allocator_type>& __x)
772        : __na_(__x.__na_),
773          __first_constructed(__x.__value_constructed),
774          __second_constructed(__x.__value_constructed)
775        {
776            const_cast<bool&>(__x.__value_constructed) = false;
777        }
778#endif // _LIBCPP_CXX03_LANG
779
780    _LIBCPP_INLINE_VISIBILITY
781    void operator()(pointer __p) _NOEXCEPT
782    {
783        if (__second_constructed)
784            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.__get_value().second));
785        if (__first_constructed)
786            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.__get_value().first));
787        if (__p)
788            __alloc_traits::deallocate(__na_, __p, 1);
789    }
790};
791
792#ifndef _LIBCPP_CXX03_LANG
793template <class _Key, class _Tp>
794struct _LIBCPP_STANDALONE_DEBUG __hash_value_type
795{
796    typedef _Key                                     key_type;
797    typedef _Tp                                      mapped_type;
798    typedef pair<const key_type, mapped_type>        value_type;
799    typedef pair<key_type&, mapped_type&>            __nc_ref_pair_type;
800    typedef pair<key_type&&, mapped_type&&>          __nc_rref_pair_type;
801
802private:
803    value_type __cc;
804
805public:
806    _LIBCPP_INLINE_VISIBILITY
807    value_type& __get_value()
808    {
809#if _LIBCPP_STD_VER > 14
810        return *_VSTD::launder(_VSTD::addressof(__cc));
811#else
812        return __cc;
813#endif
814    }
815
816    _LIBCPP_INLINE_VISIBILITY
817    const value_type& __get_value() const
818    {
819#if _LIBCPP_STD_VER > 14
820        return *_VSTD::launder(_VSTD::addressof(__cc));
821#else
822        return __cc;
823#endif
824    }
825
826    _LIBCPP_INLINE_VISIBILITY
827    __nc_ref_pair_type __ref()
828    {
829        value_type& __v = __get_value();
830        return __nc_ref_pair_type(const_cast<key_type&>(__v.first), __v.second);
831    }
832
833    _LIBCPP_INLINE_VISIBILITY
834    __nc_rref_pair_type __move()
835    {
836        value_type& __v = __get_value();
837        return __nc_rref_pair_type(
838            _VSTD::move(const_cast<key_type&>(__v.first)),
839            _VSTD::move(__v.second));
840    }
841
842    _LIBCPP_INLINE_VISIBILITY
843    __hash_value_type& operator=(const __hash_value_type& __v)
844    {
845        __ref() = __v.__get_value();
846        return *this;
847    }
848
849    _LIBCPP_INLINE_VISIBILITY
850    __hash_value_type& operator=(__hash_value_type&& __v)
851    {
852        __ref() = __v.__move();
853        return *this;
854    }
855
856    template <class _ValueTp,
857              class = typename enable_if<
858                    __is_same_uncvref<_ValueTp, value_type>::value
859                 >::type
860             >
861    _LIBCPP_INLINE_VISIBILITY
862    __hash_value_type& operator=(_ValueTp&& __v)
863    {
864        __ref() = _VSTD::forward<_ValueTp>(__v);
865        return *this;
866    }
867
868private:
869    __hash_value_type(const __hash_value_type& __v) = delete;
870    __hash_value_type(__hash_value_type&& __v) = delete;
871    template <class ..._Args>
872    explicit __hash_value_type(_Args&& ...__args) = delete;
873
874    ~__hash_value_type() = delete;
875};
876
877#else
878
879template <class _Key, class _Tp>
880struct __hash_value_type
881{
882    typedef _Key                                     key_type;
883    typedef _Tp                                      mapped_type;
884    typedef pair<const key_type, mapped_type>        value_type;
885
886private:
887    value_type __cc;
888
889public:
890    _LIBCPP_INLINE_VISIBILITY
891    value_type& __get_value() { return __cc; }
892    _LIBCPP_INLINE_VISIBILITY
893    const value_type& __get_value() const { return __cc; }
894
895private:
896   ~__hash_value_type();
897};
898
899#endif
900
901template <class _HashIterator>
902class _LIBCPP_TEMPLATE_VIS __hash_map_iterator
903{
904    _HashIterator __i_;
905
906    typedef  __hash_node_types_from_iterator<_HashIterator> _NodeTypes;
907
908public:
909    typedef forward_iterator_tag                                 iterator_category;
910    typedef typename _NodeTypes::__map_value_type                value_type;
911    typedef typename _NodeTypes::difference_type                 difference_type;
912    typedef value_type&                                          reference;
913    typedef typename _NodeTypes::__map_value_type_pointer       pointer;
914
915    _LIBCPP_INLINE_VISIBILITY
916    __hash_map_iterator() _NOEXCEPT {}
917
918    _LIBCPP_INLINE_VISIBILITY
919    __hash_map_iterator(_HashIterator __i) _NOEXCEPT : __i_(__i) {}
920
921    _LIBCPP_INLINE_VISIBILITY
922    reference operator*() const {return __i_->__get_value();}
923    _LIBCPP_INLINE_VISIBILITY
924    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__i_->__get_value());}
925
926    _LIBCPP_INLINE_VISIBILITY
927    __hash_map_iterator& operator++() {++__i_; return *this;}
928    _LIBCPP_INLINE_VISIBILITY
929    __hash_map_iterator operator++(int)
930    {
931        __hash_map_iterator __t(*this);
932        ++(*this);
933        return __t;
934    }
935
936    friend _LIBCPP_INLINE_VISIBILITY
937        bool operator==(const __hash_map_iterator& __x, const __hash_map_iterator& __y)
938        {return __x.__i_ == __y.__i_;}
939    friend _LIBCPP_INLINE_VISIBILITY
940        bool operator!=(const __hash_map_iterator& __x, const __hash_map_iterator& __y)
941        {return __x.__i_ != __y.__i_;}
942
943    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_map;
944    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
945    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
946    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
947    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
948};
949
950template <class _HashIterator>
951class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator
952{
953    _HashIterator __i_;
954
955    typedef  __hash_node_types_from_iterator<_HashIterator> _NodeTypes;
956
957public:
958    typedef forward_iterator_tag                                 iterator_category;
959    typedef typename _NodeTypes::__map_value_type                value_type;
960    typedef typename _NodeTypes::difference_type                 difference_type;
961    typedef const value_type&                                    reference;
962    typedef typename _NodeTypes::__const_map_value_type_pointer  pointer;
963
964    _LIBCPP_INLINE_VISIBILITY
965    __hash_map_const_iterator() _NOEXCEPT {}
966
967    _LIBCPP_INLINE_VISIBILITY
968    __hash_map_const_iterator(_HashIterator __i) _NOEXCEPT : __i_(__i) {}
969    _LIBCPP_INLINE_VISIBILITY
970    __hash_map_const_iterator(
971            __hash_map_iterator<typename _HashIterator::__non_const_iterator> __i)
972                 _NOEXCEPT
973                : __i_(__i.__i_) {}
974
975    _LIBCPP_INLINE_VISIBILITY
976    reference operator*() const {return __i_->__get_value();}
977    _LIBCPP_INLINE_VISIBILITY
978    pointer operator->() const {return pointer_traits<pointer>::pointer_to(__i_->__get_value());}
979
980    _LIBCPP_INLINE_VISIBILITY
981    __hash_map_const_iterator& operator++() {++__i_; return *this;}
982    _LIBCPP_INLINE_VISIBILITY
983    __hash_map_const_iterator operator++(int)
984    {
985        __hash_map_const_iterator __t(*this);
986        ++(*this);
987        return __t;
988    }
989
990    friend _LIBCPP_INLINE_VISIBILITY
991        bool operator==(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y)
992        {return __x.__i_ == __y.__i_;}
993    friend _LIBCPP_INLINE_VISIBILITY
994        bool operator!=(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y)
995        {return __x.__i_ != __y.__i_;}
996
997    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_map;
998    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
999    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
1000    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
1001};
1002
1003template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1004class unordered_multimap;
1005
1006template <class _Key, class _Tp, class _Hash = hash<_Key>, class _Pred = equal_to<_Key>,
1007          class _Alloc = allocator<pair<const _Key, _Tp> > >
1008class _LIBCPP_TEMPLATE_VIS unordered_map
1009{
1010public:
1011    // types
1012    typedef _Key                                           key_type;
1013    typedef _Tp                                            mapped_type;
1014    typedef __identity_t<_Hash>                            hasher;
1015    typedef __identity_t<_Pred>                            key_equal;
1016    typedef __identity_t<_Alloc>                           allocator_type;
1017    typedef pair<const key_type, mapped_type>              value_type;
1018    typedef value_type&                                    reference;
1019    typedef const value_type&                              const_reference;
1020    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
1021                  "Invalid allocator::value_type");
1022
1023private:
1024    typedef __hash_value_type<key_type, mapped_type>                          __value_type;
1025    typedef __unordered_map_hasher<key_type, __value_type, hasher, key_equal> __hasher;
1026    typedef __unordered_map_equal<key_type, __value_type, key_equal, hasher>  __key_equal;
1027    typedef typename __rebind_alloc_helper<allocator_traits<allocator_type>,
1028                                                 __value_type>::type          __allocator_type;
1029
1030    typedef __hash_table<__value_type, __hasher,
1031                         __key_equal,  __allocator_type>   __table;
1032
1033    __table __table_;
1034
1035    typedef typename __table::_NodeTypes                   _NodeTypes;
1036    typedef typename __table::__node_pointer               __node_pointer;
1037    typedef typename __table::__node_const_pointer         __node_const_pointer;
1038    typedef typename __table::__node_traits                __node_traits;
1039    typedef typename __table::__node_allocator             __node_allocator;
1040    typedef typename __table::__node                       __node;
1041    typedef __hash_map_node_destructor<__node_allocator>   _Dp;
1042    typedef unique_ptr<__node, _Dp>                         __node_holder;
1043    typedef allocator_traits<allocator_type>               __alloc_traits;
1044
1045    static_assert((is_same<typename __table::__container_value_type, value_type>::value), "");
1046    static_assert((is_same<typename __table::__node_value_type, __value_type>::value), "");
1047public:
1048    typedef typename __alloc_traits::pointer         pointer;
1049    typedef typename __alloc_traits::const_pointer   const_pointer;
1050    typedef typename __table::size_type              size_type;
1051    typedef typename __table::difference_type        difference_type;
1052
1053    typedef __hash_map_iterator<typename __table::iterator>       iterator;
1054    typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
1055    typedef __hash_map_iterator<typename __table::local_iterator> local_iterator;
1056    typedef __hash_map_const_iterator<typename __table::const_local_iterator> const_local_iterator;
1057
1058#if _LIBCPP_STD_VER > 14
1059    typedef __map_node_handle<__node, allocator_type> node_type;
1060    typedef __insert_return_type<iterator, node_type> insert_return_type;
1061#endif
1062
1063    template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
1064        friend class _LIBCPP_TEMPLATE_VIS unordered_map;
1065    template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
1066        friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
1067
1068    _LIBCPP_INLINE_VISIBILITY
1069    unordered_map()
1070        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
1071    {
1072        _VSTD::__debug_db_insert_c(this);
1073    }
1074    explicit unordered_map(size_type __n, const hasher& __hf = hasher(),
1075                           const key_equal& __eql = key_equal());
1076    unordered_map(size_type __n, const hasher& __hf,
1077                  const key_equal& __eql,
1078                  const allocator_type& __a);
1079    template <class _InputIterator>
1080        unordered_map(_InputIterator __first, _InputIterator __last);
1081    template <class _InputIterator>
1082        unordered_map(_InputIterator __first, _InputIterator __last,
1083                      size_type __n, const hasher& __hf = hasher(),
1084                      const key_equal& __eql = key_equal());
1085    template <class _InputIterator>
1086        unordered_map(_InputIterator __first, _InputIterator __last,
1087                      size_type __n, const hasher& __hf,
1088                      const key_equal& __eql,
1089                      const allocator_type& __a);
1090    _LIBCPP_INLINE_VISIBILITY
1091    explicit unordered_map(const allocator_type& __a);
1092    unordered_map(const unordered_map& __u);
1093    unordered_map(const unordered_map& __u, const allocator_type& __a);
1094#ifndef _LIBCPP_CXX03_LANG
1095    _LIBCPP_INLINE_VISIBILITY
1096    unordered_map(unordered_map&& __u)
1097        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
1098    unordered_map(unordered_map&& __u, const allocator_type& __a);
1099    unordered_map(initializer_list<value_type> __il);
1100    unordered_map(initializer_list<value_type> __il, size_type __n,
1101                  const hasher& __hf = hasher(), const key_equal& __eql = key_equal());
1102    unordered_map(initializer_list<value_type> __il, size_type __n,
1103                  const hasher& __hf, const key_equal& __eql,
1104                  const allocator_type& __a);
1105#endif // _LIBCPP_CXX03_LANG
1106#if _LIBCPP_STD_VER > 11
1107    _LIBCPP_INLINE_VISIBILITY
1108    unordered_map(size_type __n, const allocator_type& __a)
1109      : unordered_map(__n, hasher(), key_equal(), __a) {}
1110    _LIBCPP_INLINE_VISIBILITY
1111    unordered_map(size_type __n, const hasher& __hf, const allocator_type& __a)
1112      : unordered_map(__n, __hf, key_equal(), __a) {}
1113    template <class _InputIterator>
1114    _LIBCPP_INLINE_VISIBILITY
1115      unordered_map(_InputIterator __first, _InputIterator __last, size_type __n, const allocator_type& __a)
1116      : unordered_map(__first, __last, __n, hasher(), key_equal(), __a) {}
1117    template <class _InputIterator>
1118    _LIBCPP_INLINE_VISIBILITY
1119      unordered_map(_InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf,
1120        const allocator_type& __a)
1121      : unordered_map(__first, __last, __n, __hf, key_equal(), __a) {}
1122    _LIBCPP_INLINE_VISIBILITY
1123    unordered_map(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
1124      : unordered_map(__il, __n, hasher(), key_equal(), __a) {}
1125    _LIBCPP_INLINE_VISIBILITY
1126    unordered_map(initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1127      const allocator_type& __a)
1128      : unordered_map(__il, __n, __hf, key_equal(), __a) {}
1129#endif
1130    _LIBCPP_INLINE_VISIBILITY
1131    ~unordered_map() {
1132        static_assert(sizeof(__diagnose_unordered_container_requirements<_Key, _Hash, _Pred>(0)), "");
1133    }
1134
1135    _LIBCPP_INLINE_VISIBILITY
1136    unordered_map& operator=(const unordered_map& __u)
1137    {
1138#ifndef _LIBCPP_CXX03_LANG
1139        __table_ = __u.__table_;
1140#else
1141        if (this != _VSTD::addressof(__u)) {
1142            __table_.clear();
1143            __table_.hash_function() = __u.__table_.hash_function();
1144            __table_.key_eq() = __u.__table_.key_eq();
1145            __table_.max_load_factor() = __u.__table_.max_load_factor();
1146            __table_.__copy_assign_alloc(__u.__table_);
1147            insert(__u.begin(), __u.end());
1148        }
1149#endif
1150        return *this;
1151    }
1152#ifndef _LIBCPP_CXX03_LANG
1153    _LIBCPP_INLINE_VISIBILITY
1154    unordered_map& operator=(unordered_map&& __u)
1155        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
1156    _LIBCPP_INLINE_VISIBILITY
1157    unordered_map& operator=(initializer_list<value_type> __il);
1158#endif // _LIBCPP_CXX03_LANG
1159
1160    _LIBCPP_INLINE_VISIBILITY
1161    allocator_type get_allocator() const _NOEXCEPT
1162        {return allocator_type(__table_.__node_alloc());}
1163
1164    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1165    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
1166    _LIBCPP_INLINE_VISIBILITY
1167    size_type size() const _NOEXCEPT  {return __table_.size();}
1168    _LIBCPP_INLINE_VISIBILITY
1169    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
1170
1171    _LIBCPP_INLINE_VISIBILITY
1172    iterator       begin() _NOEXCEPT        {return __table_.begin();}
1173    _LIBCPP_INLINE_VISIBILITY
1174    iterator       end() _NOEXCEPT          {return __table_.end();}
1175    _LIBCPP_INLINE_VISIBILITY
1176    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
1177    _LIBCPP_INLINE_VISIBILITY
1178    const_iterator end()    const _NOEXCEPT {return __table_.end();}
1179    _LIBCPP_INLINE_VISIBILITY
1180    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
1181    _LIBCPP_INLINE_VISIBILITY
1182    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
1183
1184    _LIBCPP_INLINE_VISIBILITY
1185    pair<iterator, bool> insert(const value_type& __x)
1186        {return __table_.__insert_unique(__x);}
1187
1188    iterator insert(const_iterator __p, const value_type& __x) {
1189        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
1190                             "unordered_map::insert(const_iterator, const value_type&) called with an iterator not "
1191                             "referring to this unordered_map");
1192        ((void)__p);
1193        return insert(__x).first;
1194    }
1195
1196    template <class _InputIterator>
1197        _LIBCPP_INLINE_VISIBILITY
1198        void insert(_InputIterator __first, _InputIterator __last);
1199
1200#ifndef _LIBCPP_CXX03_LANG
1201    _LIBCPP_INLINE_VISIBILITY
1202    void insert(initializer_list<value_type> __il)
1203        {insert(__il.begin(), __il.end());}
1204
1205    _LIBCPP_INLINE_VISIBILITY
1206    pair<iterator, bool> insert(value_type&& __x)
1207        {return __table_.__insert_unique(_VSTD::move(__x));}
1208
1209    iterator insert(const_iterator __p, value_type&& __x) {
1210        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
1211                             "unordered_map::insert(const_iterator, const value_type&) called with an iterator not"
1212                             " referring to this unordered_map");
1213        ((void)__p);
1214        return __table_.__insert_unique(_VSTD::move(__x)).first;
1215    }
1216
1217    template <class _Pp,
1218              class = typename enable_if<is_constructible<value_type, _Pp>::value>::type>
1219        _LIBCPP_INLINE_VISIBILITY
1220        pair<iterator, bool> insert(_Pp&& __x)
1221            {return __table_.__insert_unique(_VSTD::forward<_Pp>(__x));}
1222
1223    template <class _Pp,
1224              class = typename enable_if<is_constructible<value_type, _Pp>::value>::type>
1225        _LIBCPP_INLINE_VISIBILITY
1226        iterator insert(const_iterator __p, _Pp&& __x)
1227        {
1228            _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
1229                                 "unordered_map::insert(const_iterator, value_type&&) called with an iterator not"
1230                                 " referring to this unordered_map");
1231          ((void)__p);
1232            return insert(_VSTD::forward<_Pp>(__x)).first;
1233        }
1234
1235    template <class... _Args>
1236    _LIBCPP_INLINE_VISIBILITY
1237    pair<iterator, bool> emplace(_Args&&... __args) {
1238        return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...);
1239    }
1240
1241    template <class... _Args>
1242    _LIBCPP_INLINE_VISIBILITY
1243    iterator emplace_hint(const_iterator __p, _Args&&... __args) {
1244        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
1245                             "unordered_map::emplace_hint(const_iterator, args...) called with an iterator not"
1246                             " referring to this unordered_map");
1247          ((void)__p);
1248        return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...).first;
1249    }
1250
1251#endif // _LIBCPP_CXX03_LANG
1252
1253#if _LIBCPP_STD_VER > 14
1254    template <class... _Args>
1255        _LIBCPP_INLINE_VISIBILITY
1256        pair<iterator, bool> try_emplace(const key_type& __k, _Args&&... __args)
1257    {
1258        return __table_.__emplace_unique_key_args(__k, piecewise_construct,
1259            _VSTD::forward_as_tuple(__k),
1260            _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
1261    }
1262
1263    template <class... _Args>
1264        _LIBCPP_INLINE_VISIBILITY
1265        pair<iterator, bool> try_emplace(key_type&& __k, _Args&&... __args)
1266    {
1267        return __table_.__emplace_unique_key_args(__k, piecewise_construct,
1268            _VSTD::forward_as_tuple(_VSTD::move(__k)),
1269            _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
1270    }
1271
1272    template <class... _Args>
1273        _LIBCPP_INLINE_VISIBILITY
1274        iterator try_emplace(const_iterator __h, const key_type& __k, _Args&&... __args)
1275    {
1276        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__h) == this,
1277                             "unordered_map::try_emplace(const_iterator, key, args...) called with an iterator not"
1278                             " referring to this unordered_map");
1279        ((void)__h);
1280        return try_emplace(__k, _VSTD::forward<_Args>(__args)...).first;
1281    }
1282
1283    template <class... _Args>
1284        _LIBCPP_INLINE_VISIBILITY
1285        iterator try_emplace(const_iterator __h, key_type&& __k, _Args&&... __args)
1286    {
1287        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__h) == this,
1288                             "unordered_map::try_emplace(const_iterator, key, args...) called with an iterator not"
1289                             " referring to this unordered_map");
1290        ((void)__h);
1291        return try_emplace(_VSTD::move(__k), _VSTD::forward<_Args>(__args)...).first;
1292    }
1293
1294    template <class _Vp>
1295        _LIBCPP_INLINE_VISIBILITY
1296        pair<iterator, bool> insert_or_assign(const key_type& __k, _Vp&& __v)
1297    {
1298        pair<iterator, bool> __res = __table_.__emplace_unique_key_args(__k,
1299            __k, _VSTD::forward<_Vp>(__v));
1300        if (!__res.second) {
1301            __res.first->second = _VSTD::forward<_Vp>(__v);
1302        }
1303        return __res;
1304    }
1305
1306    template <class _Vp>
1307        _LIBCPP_INLINE_VISIBILITY
1308        pair<iterator, bool> insert_or_assign(key_type&& __k, _Vp&& __v)
1309    {
1310        pair<iterator, bool> __res = __table_.__emplace_unique_key_args(__k,
1311            _VSTD::move(__k), _VSTD::forward<_Vp>(__v));
1312        if (!__res.second) {
1313            __res.first->second = _VSTD::forward<_Vp>(__v);
1314        }
1315        return __res;
1316    }
1317
1318    template <class _Vp>
1319        _LIBCPP_INLINE_VISIBILITY
1320        iterator insert_or_assign(const_iterator, const key_type& __k, _Vp&& __v)
1321     {
1322          // FIXME: Add debug mode checking for the iterator input
1323          return insert_or_assign(__k, _VSTD::forward<_Vp>(__v)).first;
1324     }
1325
1326    template <class _Vp>
1327        _LIBCPP_INLINE_VISIBILITY
1328        iterator insert_or_assign(const_iterator, key_type&& __k, _Vp&& __v)
1329     {
1330        // FIXME: Add debug mode checking for the iterator input
1331        return insert_or_assign(_VSTD::move(__k), _VSTD::forward<_Vp>(__v)).first;
1332     }
1333#endif // _LIBCPP_STD_VER > 14
1334
1335    _LIBCPP_INLINE_VISIBILITY
1336    iterator erase(const_iterator __p) {return __table_.erase(__p.__i_);}
1337    _LIBCPP_INLINE_VISIBILITY
1338    iterator erase(iterator __p)       {return __table_.erase(__p.__i_);}
1339    _LIBCPP_INLINE_VISIBILITY
1340    size_type erase(const key_type& __k) {return __table_.__erase_unique(__k);}
1341    _LIBCPP_INLINE_VISIBILITY
1342    iterator erase(const_iterator __first, const_iterator __last)
1343        {return __table_.erase(__first.__i_, __last.__i_);}
1344    _LIBCPP_INLINE_VISIBILITY
1345        void clear() _NOEXCEPT {__table_.clear();}
1346
1347#if _LIBCPP_STD_VER > 14
1348    _LIBCPP_INLINE_VISIBILITY
1349    insert_return_type insert(node_type&& __nh)
1350    {
1351        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1352            "node_type with incompatible allocator passed to unordered_map::insert()");
1353        return __table_.template __node_handle_insert_unique<
1354            node_type, insert_return_type>(_VSTD::move(__nh));
1355    }
1356    _LIBCPP_INLINE_VISIBILITY
1357    iterator insert(const_iterator __hint, node_type&& __nh)
1358    {
1359        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1360            "node_type with incompatible allocator passed to unordered_map::insert()");
1361        return __table_.template __node_handle_insert_unique<node_type>(
1362            __hint.__i_, _VSTD::move(__nh));
1363    }
1364    _LIBCPP_INLINE_VISIBILITY
1365    node_type extract(key_type const& __key)
1366    {
1367        return __table_.template __node_handle_extract<node_type>(__key);
1368    }
1369    _LIBCPP_INLINE_VISIBILITY
1370    node_type extract(const_iterator __it)
1371    {
1372        return __table_.template __node_handle_extract<node_type>(
1373            __it.__i_);
1374    }
1375
1376    template <class _H2, class _P2>
1377    _LIBCPP_INLINE_VISIBILITY
1378    void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>& __source)
1379    {
1380        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1381                       "merging container with incompatible allocator");
1382        return __table_.__node_handle_merge_unique(__source.__table_);
1383    }
1384    template <class _H2, class _P2>
1385    _LIBCPP_INLINE_VISIBILITY
1386    void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>&& __source)
1387    {
1388        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1389                       "merging container with incompatible allocator");
1390        return __table_.__node_handle_merge_unique(__source.__table_);
1391    }
1392    template <class _H2, class _P2>
1393    _LIBCPP_INLINE_VISIBILITY
1394    void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>& __source)
1395    {
1396        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1397                       "merging container with incompatible allocator");
1398        return __table_.__node_handle_merge_unique(__source.__table_);
1399    }
1400    template <class _H2, class _P2>
1401    _LIBCPP_INLINE_VISIBILITY
1402    void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>&& __source)
1403    {
1404        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1405                       "merging container with incompatible allocator");
1406        return __table_.__node_handle_merge_unique(__source.__table_);
1407    }
1408#endif
1409
1410    _LIBCPP_INLINE_VISIBILITY
1411    void swap(unordered_map& __u)
1412        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
1413        { __table_.swap(__u.__table_);}
1414
1415    _LIBCPP_INLINE_VISIBILITY
1416    hasher hash_function() const
1417        {return __table_.hash_function().hash_function();}
1418    _LIBCPP_INLINE_VISIBILITY
1419    key_equal key_eq() const
1420        {return __table_.key_eq().key_eq();}
1421
1422    _LIBCPP_INLINE_VISIBILITY
1423    iterator       find(const key_type& __k)       {return __table_.find(__k);}
1424    _LIBCPP_INLINE_VISIBILITY
1425    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
1426#if _LIBCPP_STD_VER > 17
1427    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1428    _LIBCPP_INLINE_VISIBILITY
1429    iterator       find(const _K2& __k)            {return __table_.find(__k);}
1430    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1431    _LIBCPP_INLINE_VISIBILITY
1432    const_iterator find(const _K2& __k) const      {return __table_.find(__k);}
1433#endif // _LIBCPP_STD_VER > 17
1434
1435    _LIBCPP_INLINE_VISIBILITY
1436    size_type count(const key_type& __k) const {return __table_.__count_unique(__k);}
1437#if _LIBCPP_STD_VER > 17
1438    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1439    _LIBCPP_INLINE_VISIBILITY
1440    size_type count(const _K2& __k) const      {return __table_.__count_unique(__k);}
1441#endif // _LIBCPP_STD_VER > 17
1442
1443#if _LIBCPP_STD_VER > 17
1444    _LIBCPP_INLINE_VISIBILITY
1445    bool contains(const key_type& __k) const {return find(__k) != end();}
1446
1447    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1448    _LIBCPP_INLINE_VISIBILITY
1449    bool contains(const _K2& __k) const      {return find(__k) != end();}
1450#endif // _LIBCPP_STD_VER > 17
1451
1452    _LIBCPP_INLINE_VISIBILITY
1453    pair<iterator, iterator>             equal_range(const key_type& __k)
1454        {return __table_.__equal_range_unique(__k);}
1455    _LIBCPP_INLINE_VISIBILITY
1456    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
1457        {return __table_.__equal_range_unique(__k);}
1458#if _LIBCPP_STD_VER > 17
1459    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1460    _LIBCPP_INLINE_VISIBILITY
1461    pair<iterator, iterator>             equal_range(const _K2& __k)
1462        {return __table_.__equal_range_unique(__k);}
1463    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1464    _LIBCPP_INLINE_VISIBILITY
1465    pair<const_iterator, const_iterator> equal_range(const _K2& __k) const
1466        {return __table_.__equal_range_unique(__k);}
1467#endif // _LIBCPP_STD_VER > 17
1468
1469    mapped_type& operator[](const key_type& __k);
1470#ifndef _LIBCPP_CXX03_LANG
1471    mapped_type& operator[](key_type&& __k);
1472#endif
1473
1474    mapped_type&       at(const key_type& __k);
1475    const mapped_type& at(const key_type& __k) const;
1476
1477    _LIBCPP_INLINE_VISIBILITY
1478    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
1479    _LIBCPP_INLINE_VISIBILITY
1480    size_type max_bucket_count() const _NOEXCEPT {return __table_.max_bucket_count();}
1481
1482    _LIBCPP_INLINE_VISIBILITY
1483    size_type bucket_size(size_type __n) const
1484        {return __table_.bucket_size(__n);}
1485    _LIBCPP_INLINE_VISIBILITY
1486    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
1487
1488    _LIBCPP_INLINE_VISIBILITY
1489    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
1490    _LIBCPP_INLINE_VISIBILITY
1491    local_iterator       end(size_type __n)          {return __table_.end(__n);}
1492    _LIBCPP_INLINE_VISIBILITY
1493    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
1494    _LIBCPP_INLINE_VISIBILITY
1495    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
1496    _LIBCPP_INLINE_VISIBILITY
1497    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
1498    _LIBCPP_INLINE_VISIBILITY
1499    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
1500
1501    _LIBCPP_INLINE_VISIBILITY
1502    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
1503    _LIBCPP_INLINE_VISIBILITY
1504    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
1505    _LIBCPP_INLINE_VISIBILITY
1506    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
1507    _LIBCPP_INLINE_VISIBILITY
1508    void rehash(size_type __n) {__table_.rehash(__n);}
1509    _LIBCPP_INLINE_VISIBILITY
1510    void reserve(size_type __n) {__table_.reserve(__n);}
1511
1512#if _LIBCPP_DEBUG_LEVEL == 2
1513
1514    bool __dereferenceable(const const_iterator* __i) const
1515        {return __table_.__dereferenceable(_VSTD::addressof(__i->__i_));}
1516    bool __decrementable(const const_iterator* __i) const
1517        {return __table_.__decrementable(_VSTD::addressof(__i->__i_));}
1518    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
1519        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
1520    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
1521        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
1522
1523#endif // _LIBCPP_DEBUG_LEVEL == 2
1524
1525private:
1526
1527#ifdef _LIBCPP_CXX03_LANG
1528    __node_holder __construct_node_with_key(const key_type& __k);
1529#endif
1530};
1531
1532#if _LIBCPP_STD_VER >= 17
1533template<class _InputIterator,
1534         class _Hash = hash<__iter_key_type<_InputIterator>>,
1535         class _Pred = equal_to<__iter_key_type<_InputIterator>>,
1536         class _Allocator = allocator<__iter_to_alloc_type<_InputIterator>>,
1537         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1538         class = enable_if_t<!__is_allocator<_Hash>::value>,
1539         class = enable_if_t<!is_integral<_Hash>::value>,
1540         class = enable_if_t<!__is_allocator<_Pred>::value>,
1541         class = enable_if_t<__is_allocator<_Allocator>::value>>
1542unordered_map(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
1543              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1544  -> unordered_map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>, _Hash, _Pred, _Allocator>;
1545
1546template<class _Key, class _Tp, class _Hash = hash<remove_const_t<_Key>>,
1547         class _Pred = equal_to<remove_const_t<_Key>>,
1548         class _Allocator = allocator<pair<const _Key, _Tp>>,
1549         class = enable_if_t<!__is_allocator<_Hash>::value>,
1550         class = enable_if_t<!is_integral<_Hash>::value>,
1551         class = enable_if_t<!__is_allocator<_Pred>::value>,
1552         class = enable_if_t<__is_allocator<_Allocator>::value>>
1553unordered_map(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type = 0,
1554              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1555  -> unordered_map<remove_const_t<_Key>, _Tp, _Hash, _Pred, _Allocator>;
1556
1557template<class _InputIterator, class _Allocator,
1558         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1559         class = enable_if_t<__is_allocator<_Allocator>::value>>
1560unordered_map(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
1561  -> unordered_map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
1562                   hash<__iter_key_type<_InputIterator>>, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
1563
1564template<class _InputIterator, class _Allocator,
1565         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1566         class = enable_if_t<__is_allocator<_Allocator>::value>>
1567unordered_map(_InputIterator, _InputIterator, _Allocator)
1568  -> unordered_map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
1569                   hash<__iter_key_type<_InputIterator>>, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
1570
1571template<class _InputIterator, class _Hash, class _Allocator,
1572         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1573         class = enable_if_t<!__is_allocator<_Hash>::value>,
1574         class = enable_if_t<!is_integral<_Hash>::value>,
1575         class = enable_if_t<__is_allocator<_Allocator>::value>>
1576unordered_map(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
1577  -> unordered_map<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
1578                   _Hash, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
1579
1580template<class _Key, class _Tp, class _Allocator,
1581         class = enable_if_t<__is_allocator<_Allocator>::value>>
1582unordered_map(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Allocator)
1583  -> unordered_map<remove_const_t<_Key>, _Tp,
1584                   hash<remove_const_t<_Key>>,
1585                   equal_to<remove_const_t<_Key>>, _Allocator>;
1586
1587template<class _Key, class _Tp, class _Allocator,
1588         class = enable_if_t<__is_allocator<_Allocator>::value>>
1589unordered_map(initializer_list<pair<_Key, _Tp>>, _Allocator)
1590  -> unordered_map<remove_const_t<_Key>, _Tp,
1591                   hash<remove_const_t<_Key>>,
1592                   equal_to<remove_const_t<_Key>>, _Allocator>;
1593
1594template<class _Key, class _Tp, class _Hash, class _Allocator,
1595         class = enable_if_t<!__is_allocator<_Hash>::value>,
1596         class = enable_if_t<!is_integral<_Hash>::value>,
1597         class = enable_if_t<__is_allocator<_Allocator>::value>>
1598unordered_map(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
1599  -> unordered_map<remove_const_t<_Key>, _Tp, _Hash,
1600                   equal_to<remove_const_t<_Key>>, _Allocator>;
1601#endif
1602
1603template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1604unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1605        size_type __n, const hasher& __hf, const key_equal& __eql)
1606    : __table_(__hf, __eql)
1607{
1608    _VSTD::__debug_db_insert_c(this);
1609    __table_.rehash(__n);
1610}
1611
1612template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1613unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1614        size_type __n, const hasher& __hf, const key_equal& __eql,
1615        const allocator_type& __a)
1616    : __table_(__hf, __eql, typename __table::allocator_type(__a))
1617{
1618    _VSTD::__debug_db_insert_c(this);
1619    __table_.rehash(__n);
1620}
1621
1622template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1623inline
1624unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1625        const allocator_type& __a)
1626    : __table_(typename __table::allocator_type(__a))
1627{
1628    _VSTD::__debug_db_insert_c(this);
1629}
1630
1631template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1632template <class _InputIterator>
1633unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1634        _InputIterator __first, _InputIterator __last)
1635{
1636    _VSTD::__debug_db_insert_c(this);
1637    insert(__first, __last);
1638}
1639
1640template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1641template <class _InputIterator>
1642unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1643        _InputIterator __first, _InputIterator __last, size_type __n,
1644        const hasher& __hf, const key_equal& __eql)
1645    : __table_(__hf, __eql)
1646{
1647    _VSTD::__debug_db_insert_c(this);
1648    __table_.rehash(__n);
1649    insert(__first, __last);
1650}
1651
1652template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1653template <class _InputIterator>
1654unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1655        _InputIterator __first, _InputIterator __last, size_type __n,
1656        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
1657    : __table_(__hf, __eql, typename __table::allocator_type(__a))
1658{
1659    _VSTD::__debug_db_insert_c(this);
1660    __table_.rehash(__n);
1661    insert(__first, __last);
1662}
1663
1664template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1665unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1666        const unordered_map& __u)
1667    : __table_(__u.__table_)
1668{
1669    _VSTD::__debug_db_insert_c(this);
1670    __table_.rehash(__u.bucket_count());
1671    insert(__u.begin(), __u.end());
1672}
1673
1674template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1675unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1676        const unordered_map& __u, const allocator_type& __a)
1677    : __table_(__u.__table_, typename __table::allocator_type(__a))
1678{
1679    _VSTD::__debug_db_insert_c(this);
1680    __table_.rehash(__u.bucket_count());
1681    insert(__u.begin(), __u.end());
1682}
1683
1684#ifndef _LIBCPP_CXX03_LANG
1685
1686template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1687inline
1688unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1689        unordered_map&& __u)
1690    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
1691    : __table_(_VSTD::move(__u.__table_))
1692{
1693    _VSTD::__debug_db_insert_c(this);
1694#if _LIBCPP_DEBUG_LEVEL == 2
1695    __get_db()->swap(this, &__u);
1696#endif
1697}
1698
1699template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1700unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1701        unordered_map&& __u, const allocator_type& __a)
1702    : __table_(_VSTD::move(__u.__table_), typename __table::allocator_type(__a))
1703{
1704    _VSTD::__debug_db_insert_c(this);
1705    if (__a != __u.get_allocator())
1706    {
1707        iterator __i = __u.begin();
1708        while (__u.size() != 0) {
1709            __table_.__emplace_unique(
1710                __u.__table_.remove((__i++).__i_)->__value_.__move());
1711        }
1712    }
1713#if _LIBCPP_DEBUG_LEVEL == 2
1714    else
1715        __get_db()->swap(this, &__u);
1716#endif
1717}
1718
1719template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1720unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1721        initializer_list<value_type> __il)
1722{
1723    _VSTD::__debug_db_insert_c(this);
1724    insert(__il.begin(), __il.end());
1725}
1726
1727template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1728unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1729        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1730        const key_equal& __eql)
1731    : __table_(__hf, __eql)
1732{
1733    _VSTD::__debug_db_insert_c(this);
1734    __table_.rehash(__n);
1735    insert(__il.begin(), __il.end());
1736}
1737
1738template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1739unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
1740        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1741        const key_equal& __eql, const allocator_type& __a)
1742    : __table_(__hf, __eql, typename __table::allocator_type(__a))
1743{
1744    _VSTD::__debug_db_insert_c(this);
1745    __table_.rehash(__n);
1746    insert(__il.begin(), __il.end());
1747}
1748
1749template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1750inline
1751unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>&
1752unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(unordered_map&& __u)
1753    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
1754{
1755    __table_ = _VSTD::move(__u.__table_);
1756    return *this;
1757}
1758
1759template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1760inline
1761unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>&
1762unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(
1763        initializer_list<value_type> __il)
1764{
1765    __table_.__assign_unique(__il.begin(), __il.end());
1766    return *this;
1767}
1768
1769#endif // _LIBCPP_CXX03_LANG
1770
1771template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1772template <class _InputIterator>
1773inline
1774void
1775unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
1776                                                       _InputIterator __last)
1777{
1778    for (; __first != __last; ++__first)
1779        __table_.__insert_unique(*__first);
1780}
1781
1782#ifndef _LIBCPP_CXX03_LANG
1783
1784template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1785_Tp&
1786unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](const key_type& __k)
1787{
1788    return __table_.__emplace_unique_key_args(__k,
1789        piecewise_construct, _VSTD::forward_as_tuple(__k),
1790                             _VSTD::forward_as_tuple()).first->__get_value().second;
1791}
1792
1793template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1794_Tp&
1795unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](key_type&& __k)
1796{
1797    return __table_.__emplace_unique_key_args(__k,
1798        piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__k)),
1799                             _VSTD::forward_as_tuple()).first->__get_value().second;
1800}
1801#else // _LIBCPP_CXX03_LANG
1802
1803template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1804typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
1805unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node_with_key(const key_type& __k)
1806{
1807    __node_allocator& __na = __table_.__node_alloc();
1808    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
1809    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__get_value().first), __k);
1810    __h.get_deleter().__first_constructed = true;
1811    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.__get_value().second));
1812    __h.get_deleter().__second_constructed = true;
1813    return __h;
1814}
1815
1816template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1817_Tp&
1818unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](const key_type& __k)
1819{
1820    iterator __i = find(__k);
1821    if (__i != end())
1822        return __i->second;
1823    __node_holder __h = __construct_node_with_key(__k);
1824    pair<iterator, bool> __r = __table_.__node_insert_unique(__h.get());
1825    __h.release();
1826    return __r.first->second;
1827}
1828
1829#endif // _LIBCPP_CXX03_LANG
1830
1831template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1832_Tp&
1833unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::at(const key_type& __k)
1834{
1835    iterator __i = find(__k);
1836    if (__i == end())
1837        __throw_out_of_range("unordered_map::at: key not found");
1838    return __i->second;
1839}
1840
1841template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1842const _Tp&
1843unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::at(const key_type& __k) const
1844{
1845    const_iterator __i = find(__k);
1846    if (__i == end())
1847        __throw_out_of_range("unordered_map::at: key not found");
1848    return __i->second;
1849}
1850
1851template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1852inline _LIBCPP_INLINE_VISIBILITY
1853void
1854swap(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
1855     unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
1856    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1857{
1858    __x.swap(__y);
1859}
1860
1861#if _LIBCPP_STD_VER > 17
1862template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc,
1863          class _Predicate>
1864inline _LIBCPP_INLINE_VISIBILITY
1865    typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::size_type
1866    erase_if(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __c,
1867             _Predicate __pred) {
1868  return _VSTD::__libcpp_erase_if_container(__c, __pred);
1869}
1870#endif
1871
1872template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1873bool
1874operator==(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
1875           const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
1876{
1877    if (__x.size() != __y.size())
1878        return false;
1879    typedef typename unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator
1880                                                                 const_iterator;
1881    for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end();
1882            __i != __ex; ++__i)
1883    {
1884        const_iterator __j = __y.find(__i->first);
1885        if (__j == __ey || !(*__i == *__j))
1886            return false;
1887    }
1888    return true;
1889}
1890
1891template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
1892inline _LIBCPP_INLINE_VISIBILITY
1893bool
1894operator!=(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
1895           const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
1896{
1897    return !(__x == __y);
1898}
1899
1900template <class _Key, class _Tp, class _Hash = hash<_Key>, class _Pred = equal_to<_Key>,
1901          class _Alloc = allocator<pair<const _Key, _Tp> > >
1902class _LIBCPP_TEMPLATE_VIS unordered_multimap
1903{
1904public:
1905    // types
1906    typedef _Key                                           key_type;
1907    typedef _Tp                                            mapped_type;
1908    typedef __identity_t<_Hash>                            hasher;
1909    typedef __identity_t<_Pred>                            key_equal;
1910    typedef __identity_t<_Alloc>                           allocator_type;
1911    typedef pair<const key_type, mapped_type>              value_type;
1912    typedef value_type&                                    reference;
1913    typedef const value_type&                              const_reference;
1914    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
1915                  "Invalid allocator::value_type");
1916
1917private:
1918    typedef __hash_value_type<key_type, mapped_type>                          __value_type;
1919    typedef __unordered_map_hasher<key_type, __value_type, hasher, key_equal> __hasher;
1920    typedef __unordered_map_equal<key_type, __value_type, key_equal, hasher>  __key_equal;
1921    typedef typename __rebind_alloc_helper<allocator_traits<allocator_type>,
1922                                                 __value_type>::type          __allocator_type;
1923
1924    typedef __hash_table<__value_type, __hasher,
1925                         __key_equal,  __allocator_type>   __table;
1926
1927    __table __table_;
1928
1929    typedef typename __table::_NodeTypes                   _NodeTypes;
1930    typedef typename __table::__node_traits                __node_traits;
1931    typedef typename __table::__node_allocator             __node_allocator;
1932    typedef typename __table::__node                       __node;
1933    typedef __hash_map_node_destructor<__node_allocator>   _Dp;
1934    typedef unique_ptr<__node, _Dp>                         __node_holder;
1935    typedef allocator_traits<allocator_type>               __alloc_traits;
1936    static_assert((is_same<typename __node_traits::size_type,
1937                          typename __alloc_traits::size_type>::value),
1938                 "Allocator uses different size_type for different types");
1939public:
1940    typedef typename __alloc_traits::pointer         pointer;
1941    typedef typename __alloc_traits::const_pointer   const_pointer;
1942    typedef typename __table::size_type              size_type;
1943    typedef typename __table::difference_type        difference_type;
1944
1945    typedef __hash_map_iterator<typename __table::iterator>       iterator;
1946    typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
1947    typedef __hash_map_iterator<typename __table::local_iterator> local_iterator;
1948    typedef __hash_map_const_iterator<typename __table::const_local_iterator> const_local_iterator;
1949
1950#if _LIBCPP_STD_VER > 14
1951    typedef __map_node_handle<__node, allocator_type> node_type;
1952#endif
1953
1954    template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
1955        friend class _LIBCPP_TEMPLATE_VIS unordered_map;
1956    template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
1957        friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
1958
1959    _LIBCPP_INLINE_VISIBILITY
1960    unordered_multimap()
1961        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
1962    {
1963        _VSTD::__debug_db_insert_c(this);
1964    }
1965    explicit unordered_multimap(size_type __n, const hasher& __hf = hasher(),
1966                                const key_equal& __eql = key_equal());
1967    unordered_multimap(size_type __n, const hasher& __hf,
1968                                const key_equal& __eql,
1969                                const allocator_type& __a);
1970    template <class _InputIterator>
1971        unordered_multimap(_InputIterator __first, _InputIterator __last);
1972    template <class _InputIterator>
1973        unordered_multimap(_InputIterator __first, _InputIterator __last,
1974                      size_type __n, const hasher& __hf = hasher(),
1975                      const key_equal& __eql = key_equal());
1976    template <class _InputIterator>
1977        unordered_multimap(_InputIterator __first, _InputIterator __last,
1978                      size_type __n, const hasher& __hf,
1979                      const key_equal& __eql,
1980                      const allocator_type& __a);
1981    _LIBCPP_INLINE_VISIBILITY
1982    explicit unordered_multimap(const allocator_type& __a);
1983    unordered_multimap(const unordered_multimap& __u);
1984    unordered_multimap(const unordered_multimap& __u, const allocator_type& __a);
1985#ifndef _LIBCPP_CXX03_LANG
1986    _LIBCPP_INLINE_VISIBILITY
1987    unordered_multimap(unordered_multimap&& __u)
1988        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
1989    unordered_multimap(unordered_multimap&& __u, const allocator_type& __a);
1990    unordered_multimap(initializer_list<value_type> __il);
1991    unordered_multimap(initializer_list<value_type> __il, size_type __n,
1992                       const hasher& __hf = hasher(),
1993                       const key_equal& __eql = key_equal());
1994    unordered_multimap(initializer_list<value_type> __il, size_type __n,
1995                       const hasher& __hf, const key_equal& __eql,
1996                       const allocator_type& __a);
1997#endif // _LIBCPP_CXX03_LANG
1998#if _LIBCPP_STD_VER > 11
1999    _LIBCPP_INLINE_VISIBILITY
2000    unordered_multimap(size_type __n, const allocator_type& __a)
2001      : unordered_multimap(__n, hasher(), key_equal(), __a) {}
2002    _LIBCPP_INLINE_VISIBILITY
2003    unordered_multimap(size_type __n, const hasher& __hf, const allocator_type& __a)
2004      : unordered_multimap(__n, __hf, key_equal(), __a) {}
2005    template <class _InputIterator>
2006    _LIBCPP_INLINE_VISIBILITY
2007      unordered_multimap(_InputIterator __first, _InputIterator __last, size_type __n, const allocator_type& __a)
2008      : unordered_multimap(__first, __last, __n, hasher(), key_equal(), __a) {}
2009    template <class _InputIterator>
2010    _LIBCPP_INLINE_VISIBILITY
2011      unordered_multimap(_InputIterator __first, _InputIterator __last, size_type __n, const hasher& __hf,
2012        const allocator_type& __a)
2013      : unordered_multimap(__first, __last, __n, __hf, key_equal(), __a) {}
2014    _LIBCPP_INLINE_VISIBILITY
2015    unordered_multimap(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
2016      : unordered_multimap(__il, __n, hasher(), key_equal(), __a) {}
2017    _LIBCPP_INLINE_VISIBILITY
2018    unordered_multimap(initializer_list<value_type> __il, size_type __n, const hasher& __hf,
2019      const allocator_type& __a)
2020      : unordered_multimap(__il, __n, __hf, key_equal(), __a) {}
2021#endif
2022    _LIBCPP_INLINE_VISIBILITY
2023    ~unordered_multimap() {
2024        static_assert(sizeof(__diagnose_unordered_container_requirements<_Key, _Hash, _Pred>(0)), "");
2025    }
2026
2027    _LIBCPP_INLINE_VISIBILITY
2028    unordered_multimap& operator=(const unordered_multimap& __u)
2029    {
2030#ifndef _LIBCPP_CXX03_LANG
2031        __table_ = __u.__table_;
2032#else
2033        if (this != _VSTD::addressof(__u)) {
2034            __table_.clear();
2035            __table_.hash_function() = __u.__table_.hash_function();
2036            __table_.key_eq() = __u.__table_.key_eq();
2037            __table_.max_load_factor() = __u.__table_.max_load_factor();
2038            __table_.__copy_assign_alloc(__u.__table_);
2039            insert(__u.begin(), __u.end());
2040        }
2041#endif
2042        return *this;
2043    }
2044#ifndef _LIBCPP_CXX03_LANG
2045    _LIBCPP_INLINE_VISIBILITY
2046    unordered_multimap& operator=(unordered_multimap&& __u)
2047        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
2048    _LIBCPP_INLINE_VISIBILITY
2049    unordered_multimap& operator=(initializer_list<value_type> __il);
2050#endif // _LIBCPP_CXX03_LANG
2051
2052    _LIBCPP_INLINE_VISIBILITY
2053    allocator_type get_allocator() const _NOEXCEPT
2054        {return allocator_type(__table_.__node_alloc());}
2055
2056    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
2057    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
2058    _LIBCPP_INLINE_VISIBILITY
2059    size_type size() const _NOEXCEPT  {return __table_.size();}
2060    _LIBCPP_INLINE_VISIBILITY
2061    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
2062
2063    _LIBCPP_INLINE_VISIBILITY
2064    iterator       begin() _NOEXCEPT        {return __table_.begin();}
2065    _LIBCPP_INLINE_VISIBILITY
2066    iterator       end() _NOEXCEPT          {return __table_.end();}
2067    _LIBCPP_INLINE_VISIBILITY
2068    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
2069    _LIBCPP_INLINE_VISIBILITY
2070    const_iterator end()    const _NOEXCEPT {return __table_.end();}
2071    _LIBCPP_INLINE_VISIBILITY
2072    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
2073    _LIBCPP_INLINE_VISIBILITY
2074    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
2075
2076    _LIBCPP_INLINE_VISIBILITY
2077    iterator insert(const value_type& __x) {return __table_.__insert_multi(__x);}
2078
2079    _LIBCPP_INLINE_VISIBILITY
2080    iterator insert(const_iterator __p, const value_type& __x)
2081        {return __table_.__insert_multi(__p.__i_, __x);}
2082
2083    template <class _InputIterator>
2084    _LIBCPP_INLINE_VISIBILITY
2085    void insert(_InputIterator __first, _InputIterator __last);
2086
2087#ifndef _LIBCPP_CXX03_LANG
2088    _LIBCPP_INLINE_VISIBILITY
2089    void insert(initializer_list<value_type> __il)
2090        {insert(__il.begin(), __il.end());}
2091    _LIBCPP_INLINE_VISIBILITY
2092    iterator insert(value_type&& __x) {return __table_.__insert_multi(_VSTD::move(__x));}
2093
2094    _LIBCPP_INLINE_VISIBILITY
2095    iterator insert(const_iterator __p, value_type&& __x)
2096        {return __table_.__insert_multi(__p.__i_, _VSTD::move(__x));}
2097
2098    template <class _Pp,
2099              class = typename enable_if<is_constructible<value_type, _Pp>::value>::type>
2100    _LIBCPP_INLINE_VISIBILITY
2101    iterator insert(_Pp&& __x)
2102        {return __table_.__insert_multi(_VSTD::forward<_Pp>(__x));}
2103
2104    template <class _Pp,
2105              class = typename enable_if<is_constructible<value_type, _Pp>::value>::type>
2106    _LIBCPP_INLINE_VISIBILITY
2107    iterator insert(const_iterator __p, _Pp&& __x)
2108        {return __table_.__insert_multi(__p.__i_, _VSTD::forward<_Pp>(__x));}
2109
2110    template <class... _Args>
2111    iterator emplace(_Args&&... __args) {
2112        return __table_.__emplace_multi(_VSTD::forward<_Args>(__args)...);
2113    }
2114
2115    template <class... _Args>
2116    iterator emplace_hint(const_iterator __p, _Args&&... __args) {
2117        return __table_.__emplace_hint_multi(__p.__i_, _VSTD::forward<_Args>(__args)...);
2118    }
2119#endif // _LIBCPP_CXX03_LANG
2120
2121
2122    _LIBCPP_INLINE_VISIBILITY
2123    iterator erase(const_iterator __p) {return __table_.erase(__p.__i_);}
2124    _LIBCPP_INLINE_VISIBILITY
2125    iterator erase(iterator __p)       {return __table_.erase(__p.__i_);}
2126    _LIBCPP_INLINE_VISIBILITY
2127    size_type erase(const key_type& __k) {return __table_.__erase_multi(__k);}
2128    _LIBCPP_INLINE_VISIBILITY
2129    iterator erase(const_iterator __first, const_iterator __last)
2130        {return __table_.erase(__first.__i_, __last.__i_);}
2131    _LIBCPP_INLINE_VISIBILITY
2132    void clear() _NOEXCEPT {__table_.clear();}
2133
2134#if _LIBCPP_STD_VER > 14
2135    _LIBCPP_INLINE_VISIBILITY
2136    iterator insert(node_type&& __nh)
2137    {
2138        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
2139            "node_type with incompatible allocator passed to unordered_multimap::insert()");
2140        return __table_.template __node_handle_insert_multi<node_type>(
2141            _VSTD::move(__nh));
2142    }
2143    _LIBCPP_INLINE_VISIBILITY
2144    iterator insert(const_iterator __hint, node_type&& __nh)
2145    {
2146        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
2147            "node_type with incompatible allocator passed to unordered_multimap::insert()");
2148        return __table_.template __node_handle_insert_multi<node_type>(
2149            __hint.__i_, _VSTD::move(__nh));
2150    }
2151    _LIBCPP_INLINE_VISIBILITY
2152    node_type extract(key_type const& __key)
2153    {
2154        return __table_.template __node_handle_extract<node_type>(__key);
2155    }
2156    _LIBCPP_INLINE_VISIBILITY
2157    node_type extract(const_iterator __it)
2158    {
2159        return __table_.template __node_handle_extract<node_type>(
2160            __it.__i_);
2161    }
2162
2163    template <class _H2, class _P2>
2164    _LIBCPP_INLINE_VISIBILITY
2165    void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>& __source)
2166    {
2167        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
2168                       "merging container with incompatible allocator");
2169        return __table_.__node_handle_merge_multi(__source.__table_);
2170    }
2171    template <class _H2, class _P2>
2172    _LIBCPP_INLINE_VISIBILITY
2173    void merge(unordered_multimap<key_type, mapped_type, _H2, _P2, allocator_type>&& __source)
2174    {
2175        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
2176                       "merging container with incompatible allocator");
2177        return __table_.__node_handle_merge_multi(__source.__table_);
2178    }
2179    template <class _H2, class _P2>
2180    _LIBCPP_INLINE_VISIBILITY
2181    void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>& __source)
2182    {
2183        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
2184                       "merging container with incompatible allocator");
2185        return __table_.__node_handle_merge_multi(__source.__table_);
2186    }
2187    template <class _H2, class _P2>
2188    _LIBCPP_INLINE_VISIBILITY
2189    void merge(unordered_map<key_type, mapped_type, _H2, _P2, allocator_type>&& __source)
2190    {
2191        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
2192                       "merging container with incompatible allocator");
2193        return __table_.__node_handle_merge_multi(__source.__table_);
2194    }
2195#endif
2196
2197    _LIBCPP_INLINE_VISIBILITY
2198    void swap(unordered_multimap& __u)
2199        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
2200        {__table_.swap(__u.__table_);}
2201
2202    _LIBCPP_INLINE_VISIBILITY
2203    hasher hash_function() const
2204        {return __table_.hash_function().hash_function();}
2205    _LIBCPP_INLINE_VISIBILITY
2206    key_equal key_eq() const
2207        {return __table_.key_eq().key_eq();}
2208
2209    _LIBCPP_INLINE_VISIBILITY
2210    iterator       find(const key_type& __k)       {return __table_.find(__k);}
2211    _LIBCPP_INLINE_VISIBILITY
2212    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
2213#if _LIBCPP_STD_VER > 17
2214    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2215    _LIBCPP_INLINE_VISIBILITY
2216    iterator       find(const _K2& __k)            {return __table_.find(__k);}
2217    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2218    _LIBCPP_INLINE_VISIBILITY
2219    const_iterator find(const _K2& __k) const      {return __table_.find(__k);}
2220#endif // _LIBCPP_STD_VER > 17
2221
2222    _LIBCPP_INLINE_VISIBILITY
2223    size_type count(const key_type& __k) const {return __table_.__count_multi(__k);}
2224#if _LIBCPP_STD_VER > 17
2225    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2226    _LIBCPP_INLINE_VISIBILITY
2227    size_type count(const _K2& __k) const      {return __table_.__count_multi(__k);}
2228#endif // _LIBCPP_STD_VER > 17
2229
2230#if _LIBCPP_STD_VER > 17
2231    _LIBCPP_INLINE_VISIBILITY
2232    bool contains(const key_type& __k) const {return find(__k) != end();}
2233
2234    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2235    _LIBCPP_INLINE_VISIBILITY
2236    bool contains(const _K2& __k) const      {return find(__k) != end();}
2237#endif // _LIBCPP_STD_VER > 17
2238
2239    _LIBCPP_INLINE_VISIBILITY
2240    pair<iterator, iterator>             equal_range(const key_type& __k)
2241        {return __table_.__equal_range_multi(__k);}
2242    _LIBCPP_INLINE_VISIBILITY
2243    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
2244        {return __table_.__equal_range_multi(__k);}
2245#if _LIBCPP_STD_VER > 17
2246    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2247    _LIBCPP_INLINE_VISIBILITY
2248    pair<iterator, iterator>             equal_range(const _K2& __k)
2249        {return __table_.__equal_range_multi(__k);}
2250    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
2251    _LIBCPP_INLINE_VISIBILITY
2252    pair<const_iterator, const_iterator> equal_range(const _K2& __k) const
2253        {return __table_.__equal_range_multi(__k);}
2254#endif // _LIBCPP_STD_VER > 17
2255
2256    _LIBCPP_INLINE_VISIBILITY
2257    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
2258    _LIBCPP_INLINE_VISIBILITY
2259    size_type max_bucket_count() const _NOEXCEPT
2260        {return __table_.max_bucket_count();}
2261
2262    _LIBCPP_INLINE_VISIBILITY
2263    size_type bucket_size(size_type __n) const
2264        {return __table_.bucket_size(__n);}
2265    _LIBCPP_INLINE_VISIBILITY
2266    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
2267
2268    _LIBCPP_INLINE_VISIBILITY
2269    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
2270    _LIBCPP_INLINE_VISIBILITY
2271    local_iterator       end(size_type __n)          {return __table_.end(__n);}
2272    _LIBCPP_INLINE_VISIBILITY
2273    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
2274    _LIBCPP_INLINE_VISIBILITY
2275    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
2276    _LIBCPP_INLINE_VISIBILITY
2277    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
2278    _LIBCPP_INLINE_VISIBILITY
2279    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
2280
2281    _LIBCPP_INLINE_VISIBILITY
2282    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
2283    _LIBCPP_INLINE_VISIBILITY
2284    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
2285    _LIBCPP_INLINE_VISIBILITY
2286    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
2287    _LIBCPP_INLINE_VISIBILITY
2288    void rehash(size_type __n) {__table_.rehash(__n);}
2289    _LIBCPP_INLINE_VISIBILITY
2290    void reserve(size_type __n) {__table_.reserve(__n);}
2291
2292#if _LIBCPP_DEBUG_LEVEL == 2
2293
2294    bool __dereferenceable(const const_iterator* __i) const
2295        {return __table_.__dereferenceable(_VSTD::addressof(__i->__i_));}
2296    bool __decrementable(const const_iterator* __i) const
2297        {return __table_.__decrementable(_VSTD::addressof(__i->__i_));}
2298    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
2299        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
2300    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
2301        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
2302
2303#endif // _LIBCPP_DEBUG_LEVEL == 2
2304
2305
2306};
2307
2308#if _LIBCPP_STD_VER >= 17
2309template<class _InputIterator,
2310         class _Hash = hash<__iter_key_type<_InputIterator>>,
2311         class _Pred = equal_to<__iter_key_type<_InputIterator>>,
2312         class _Allocator = allocator<__iter_to_alloc_type<_InputIterator>>,
2313         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
2314         class = enable_if_t<!__is_allocator<_Hash>::value>,
2315         class = enable_if_t<!is_integral<_Hash>::value>,
2316         class = enable_if_t<!__is_allocator<_Pred>::value>,
2317         class = enable_if_t<__is_allocator<_Allocator>::value>>
2318unordered_multimap(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
2319                   _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
2320  -> unordered_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>, _Hash, _Pred, _Allocator>;
2321
2322template<class _Key, class _Tp, class _Hash = hash<remove_const_t<_Key>>,
2323         class _Pred = equal_to<remove_const_t<_Key>>,
2324         class _Allocator = allocator<pair<const _Key, _Tp>>,
2325         class = enable_if_t<!__is_allocator<_Hash>::value>,
2326         class = enable_if_t<!is_integral<_Hash>::value>,
2327         class = enable_if_t<!__is_allocator<_Pred>::value>,
2328         class = enable_if_t<__is_allocator<_Allocator>::value>>
2329unordered_multimap(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type = 0,
2330                   _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
2331  -> unordered_multimap<remove_const_t<_Key>, _Tp, _Hash, _Pred, _Allocator>;
2332
2333template<class _InputIterator, class _Allocator,
2334         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
2335         class = enable_if_t<__is_allocator<_Allocator>::value>>
2336unordered_multimap(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
2337  -> unordered_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
2338                        hash<__iter_key_type<_InputIterator>>, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
2339
2340template<class _InputIterator, class _Allocator,
2341         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
2342         class = enable_if_t<__is_allocator<_Allocator>::value>>
2343unordered_multimap(_InputIterator, _InputIterator, _Allocator)
2344  -> unordered_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
2345                        hash<__iter_key_type<_InputIterator>>, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
2346
2347template<class _InputIterator, class _Hash, class _Allocator,
2348         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
2349         class = enable_if_t<!__is_allocator<_Hash>::value>,
2350         class = enable_if_t<!is_integral<_Hash>::value>,
2351         class = enable_if_t<__is_allocator<_Allocator>::value>>
2352unordered_multimap(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
2353  -> unordered_multimap<__iter_key_type<_InputIterator>, __iter_mapped_type<_InputIterator>,
2354                        _Hash, equal_to<__iter_key_type<_InputIterator>>, _Allocator>;
2355
2356template<class _Key, class _Tp, class _Allocator,
2357         class = enable_if_t<__is_allocator<_Allocator>::value>>
2358unordered_multimap(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Allocator)
2359  -> unordered_multimap<remove_const_t<_Key>, _Tp,
2360                        hash<remove_const_t<_Key>>,
2361                        equal_to<remove_const_t<_Key>>, _Allocator>;
2362
2363template<class _Key, class _Tp, class _Allocator,
2364         class = enable_if_t<__is_allocator<_Allocator>::value>>
2365unordered_multimap(initializer_list<pair<_Key, _Tp>>, _Allocator)
2366  -> unordered_multimap<remove_const_t<_Key>, _Tp,
2367                        hash<remove_const_t<_Key>>,
2368                        equal_to<remove_const_t<_Key>>, _Allocator>;
2369
2370template<class _Key, class _Tp, class _Hash, class _Allocator,
2371         class = enable_if_t<!__is_allocator<_Hash>::value>,
2372         class = enable_if_t<!is_integral<_Hash>::value>,
2373         class = enable_if_t<__is_allocator<_Allocator>::value>>
2374unordered_multimap(initializer_list<pair<_Key, _Tp>>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
2375  -> unordered_multimap<remove_const_t<_Key>, _Tp, _Hash,
2376                        equal_to<remove_const_t<_Key>>, _Allocator>;
2377#endif
2378
2379template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2380unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2381        size_type __n, const hasher& __hf, const key_equal& __eql)
2382    : __table_(__hf, __eql)
2383{
2384    _VSTD::__debug_db_insert_c(this);
2385    __table_.rehash(__n);
2386}
2387
2388template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2389unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2390        size_type __n, const hasher& __hf, const key_equal& __eql,
2391        const allocator_type& __a)
2392    : __table_(__hf, __eql, typename __table::allocator_type(__a))
2393{
2394    _VSTD::__debug_db_insert_c(this);
2395    __table_.rehash(__n);
2396}
2397
2398template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2399template <class _InputIterator>
2400unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2401        _InputIterator __first, _InputIterator __last)
2402{
2403    _VSTD::__debug_db_insert_c(this);
2404    insert(__first, __last);
2405}
2406
2407template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2408template <class _InputIterator>
2409unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2410        _InputIterator __first, _InputIterator __last, size_type __n,
2411        const hasher& __hf, const key_equal& __eql)
2412    : __table_(__hf, __eql)
2413{
2414    _VSTD::__debug_db_insert_c(this);
2415    __table_.rehash(__n);
2416    insert(__first, __last);
2417}
2418
2419template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2420template <class _InputIterator>
2421unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2422        _InputIterator __first, _InputIterator __last, size_type __n,
2423        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
2424    : __table_(__hf, __eql, typename __table::allocator_type(__a))
2425{
2426    _VSTD::__debug_db_insert_c(this);
2427    __table_.rehash(__n);
2428    insert(__first, __last);
2429}
2430
2431template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2432inline
2433unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2434        const allocator_type& __a)
2435    : __table_(typename __table::allocator_type(__a))
2436{
2437    _VSTD::__debug_db_insert_c(this);
2438}
2439
2440template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2441unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2442        const unordered_multimap& __u)
2443    : __table_(__u.__table_)
2444{
2445    _VSTD::__debug_db_insert_c(this);
2446    __table_.rehash(__u.bucket_count());
2447    insert(__u.begin(), __u.end());
2448}
2449
2450template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2451unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2452        const unordered_multimap& __u, const allocator_type& __a)
2453    : __table_(__u.__table_, typename __table::allocator_type(__a))
2454{
2455    _VSTD::__debug_db_insert_c(this);
2456    __table_.rehash(__u.bucket_count());
2457    insert(__u.begin(), __u.end());
2458}
2459
2460#ifndef _LIBCPP_CXX03_LANG
2461
2462template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2463inline
2464unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2465        unordered_multimap&& __u)
2466    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
2467    : __table_(_VSTD::move(__u.__table_))
2468{
2469    _VSTD::__debug_db_insert_c(this);
2470#if _LIBCPP_DEBUG_LEVEL == 2
2471    __get_db()->swap(this, &__u);
2472#endif
2473}
2474
2475template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2476unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2477        unordered_multimap&& __u, const allocator_type& __a)
2478    : __table_(_VSTD::move(__u.__table_), typename __table::allocator_type(__a))
2479{
2480    _VSTD::__debug_db_insert_c(this);
2481    if (__a != __u.get_allocator())
2482    {
2483        iterator __i = __u.begin();
2484        while (__u.size() != 0)
2485        {
2486            __table_.__insert_multi(
2487                __u.__table_.remove((__i++).__i_)->__value_.__move());
2488        }
2489    }
2490#if _LIBCPP_DEBUG_LEVEL == 2
2491    else
2492        __get_db()->swap(this, &__u);
2493#endif
2494}
2495
2496template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2497unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2498        initializer_list<value_type> __il)
2499{
2500    _VSTD::__debug_db_insert_c(this);
2501    insert(__il.begin(), __il.end());
2502}
2503
2504template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2505unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2506        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
2507        const key_equal& __eql)
2508    : __table_(__hf, __eql)
2509{
2510    _VSTD::__debug_db_insert_c(this);
2511    __table_.rehash(__n);
2512    insert(__il.begin(), __il.end());
2513}
2514
2515template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2516unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
2517        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
2518        const key_equal& __eql, const allocator_type& __a)
2519    : __table_(__hf, __eql, typename __table::allocator_type(__a))
2520{
2521    _VSTD::__debug_db_insert_c(this);
2522    __table_.rehash(__n);
2523    insert(__il.begin(), __il.end());
2524}
2525
2526template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2527inline
2528unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>&
2529unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(unordered_multimap&& __u)
2530    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
2531{
2532    __table_ = _VSTD::move(__u.__table_);
2533    return *this;
2534}
2535
2536template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2537inline
2538unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>&
2539unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(
2540        initializer_list<value_type> __il)
2541{
2542    __table_.__assign_multi(__il.begin(), __il.end());
2543    return *this;
2544}
2545
2546#endif // _LIBCPP_CXX03_LANG
2547
2548
2549
2550template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2551template <class _InputIterator>
2552inline
2553void
2554unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
2555                                                            _InputIterator __last)
2556{
2557    for (; __first != __last; ++__first)
2558        __table_.__insert_multi(*__first);
2559}
2560
2561template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2562inline _LIBCPP_INLINE_VISIBILITY
2563void
2564swap(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
2565     unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
2566    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
2567{
2568    __x.swap(__y);
2569}
2570
2571#if _LIBCPP_STD_VER > 17
2572template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc,
2573          class _Predicate>
2574inline _LIBCPP_INLINE_VISIBILITY
2575    typename unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::size_type
2576    erase_if(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __c,
2577             _Predicate __pred) {
2578  return _VSTD::__libcpp_erase_if_container(__c, __pred);
2579}
2580#endif
2581
2582template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2583bool
2584operator==(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
2585           const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
2586{
2587    if (__x.size() != __y.size())
2588        return false;
2589    typedef typename unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator
2590                                                                 const_iterator;
2591    typedef pair<const_iterator, const_iterator> _EqRng;
2592    for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;)
2593    {
2594        _EqRng __xeq = __x.equal_range(__i->first);
2595        _EqRng __yeq = __y.equal_range(__i->first);
2596        if (_VSTD::distance(__xeq.first, __xeq.second) !=
2597            _VSTD::distance(__yeq.first, __yeq.second) ||
2598                  !_VSTD::is_permutation(__xeq.first, __xeq.second, __yeq.first))
2599            return false;
2600        __i = __xeq.second;
2601    }
2602    return true;
2603}
2604
2605template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
2606inline _LIBCPP_INLINE_VISIBILITY
2607bool
2608operator!=(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
2609           const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
2610{
2611    return !(__x == __y);
2612}
2613
2614_LIBCPP_END_NAMESPACE_STD
2615
2616#endif // _LIBCPP_UNORDERED_MAP
2617