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_SET
11#define _LIBCPP_UNORDERED_SET
12
13/*
14
15    unordered_set synopsis
16
17#include <initializer_list>
18
19namespace std
20{
21
22template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
23          class Alloc = allocator<Value>>
24class unordered_set
25{
26public:
27    // types
28    typedef Value                                                      key_type;
29    typedef key_type                                                   value_type;
30    typedef Hash                                                       hasher;
31    typedef Pred                                                       key_equal;
32    typedef Alloc                                                      allocator_type;
33    typedef value_type&                                                reference;
34    typedef const value_type&                                          const_reference;
35    typedef typename allocator_traits<allocator_type>::pointer         pointer;
36    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
37    typedef typename allocator_traits<allocator_type>::size_type       size_type;
38    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
39
40    typedef /unspecified/ iterator;
41    typedef /unspecified/ const_iterator;
42    typedef /unspecified/ local_iterator;
43    typedef /unspecified/ const_local_iterator;
44
45    typedef unspecified node_type unspecified;                            // C++17
46    typedef INSERT_RETURN_TYPE<iterator, node_type> insert_return_type;   // C++17
47
48    unordered_set()
49        noexcept(
50            is_nothrow_default_constructible<hasher>::value &&
51            is_nothrow_default_constructible<key_equal>::value &&
52            is_nothrow_default_constructible<allocator_type>::value);
53    explicit unordered_set(size_type n, const hasher& hf = hasher(),
54                           const key_equal& eql = key_equal(),
55                           const allocator_type& a = allocator_type());
56    template <class InputIterator>
57        unordered_set(InputIterator f, InputIterator l,
58                      size_type n = 0, const hasher& hf = hasher(),
59                      const key_equal& eql = key_equal(),
60                      const allocator_type& a = allocator_type());
61    explicit unordered_set(const allocator_type&);
62    unordered_set(const unordered_set&);
63    unordered_set(const unordered_set&, const Allocator&);
64    unordered_set(unordered_set&&)
65        noexcept(
66            is_nothrow_move_constructible<hasher>::value &&
67            is_nothrow_move_constructible<key_equal>::value &&
68            is_nothrow_move_constructible<allocator_type>::value);
69    unordered_set(unordered_set&&, const Allocator&);
70    unordered_set(initializer_list<value_type>, size_type n = 0,
71                  const hasher& hf = hasher(), const key_equal& eql = key_equal(),
72                  const allocator_type& a = allocator_type());
73    unordered_set(size_type n, const allocator_type& a); // C++14
74    unordered_set(size_type n, const hasher& hf, const allocator_type& a); // C++14
75    template <class InputIterator>
76      unordered_set(InputIterator f, InputIterator l, size_type n, const allocator_type& a); // C++14
77    template <class InputIterator>
78      unordered_set(InputIterator f, InputIterator l, size_type n,
79                    const hasher& hf,  const allocator_type& a); // C++14
80    unordered_set(initializer_list<value_type> il, size_type n, const allocator_type& a); // C++14
81    unordered_set(initializer_list<value_type> il, size_type n,
82                  const hasher& hf,  const allocator_type& a); // C++14
83    ~unordered_set();
84    unordered_set& operator=(const unordered_set&);
85    unordered_set& operator=(unordered_set&&)
86        noexcept(
87            allocator_type::propagate_on_container_move_assignment::value &&
88            is_nothrow_move_assignable<allocator_type>::value &&
89            is_nothrow_move_assignable<hasher>::value &&
90            is_nothrow_move_assignable<key_equal>::value);
91    unordered_set& operator=(initializer_list<value_type>);
92
93    allocator_type get_allocator() const noexcept;
94
95    bool      empty() const noexcept;
96    size_type size() const noexcept;
97    size_type max_size() const noexcept;
98
99    iterator       begin() noexcept;
100    iterator       end() noexcept;
101    const_iterator begin()  const noexcept;
102    const_iterator end()    const noexcept;
103    const_iterator cbegin() const noexcept;
104    const_iterator cend()   const noexcept;
105
106    template <class... Args>
107        pair<iterator, bool> emplace(Args&&... args);
108    template <class... Args>
109        iterator emplace_hint(const_iterator position, Args&&... args);
110    pair<iterator, bool> insert(const value_type& obj);
111    pair<iterator, bool> insert(value_type&& obj);
112    iterator insert(const_iterator hint, const value_type& obj);
113    iterator insert(const_iterator hint, value_type&& obj);
114    template <class InputIterator>
115        void insert(InputIterator first, InputIterator last);
116    void insert(initializer_list<value_type>);
117
118    node_type extract(const_iterator position);                       // C++17
119    node_type extract(const key_type& x);                             // C++17
120    insert_return_type insert(node_type&& nh);                        // C++17
121    iterator           insert(const_iterator hint, node_type&& nh);   // C++17
122
123    iterator erase(const_iterator position);
124    iterator erase(iterator position);  // C++14
125    size_type erase(const key_type& k);
126    iterator erase(const_iterator first, const_iterator last);
127    void clear() noexcept;
128
129    template<class H2, class P2>
130      void merge(unordered_set<Key, H2, P2, Allocator>& source);         // C++17
131    template<class H2, class P2>
132      void merge(unordered_set<Key, H2, P2, Allocator>&& source);        // C++17
133    template<class H2, class P2>
134      void merge(unordered_multiset<Key, H2, P2, Allocator>& source);    // C++17
135    template<class H2, class P2>
136      void merge(unordered_multiset<Key, H2, P2, Allocator>&& source);   // C++17
137
138    void swap(unordered_set&)
139       noexcept(allocator_traits<Allocator>::is_always_equal::value &&
140                 noexcept(swap(declval<hasher&>(), declval<hasher&>())) &&
141                 noexcept(swap(declval<key_equal&>(), declval<key_equal&>()))); // C++17
142
143    hasher hash_function() const;
144    key_equal key_eq() const;
145
146    iterator       find(const key_type& k);
147    const_iterator find(const key_type& k) const;
148    template<typename K>
149        iterator find(const K& x);              // C++20
150    template<typename K>
151        const_iterator find(const K& x) const;  // C++20
152    size_type count(const key_type& k) const;
153    template<typename K>
154        size_type count(const K& k) const; // C++20
155    bool contains(const key_type& k) const; // C++20
156    template<typename K>
157        bool contains(const K& k) const; // C++20
158    pair<iterator, iterator>             equal_range(const key_type& k);
159    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
160    template<typename K>
161        pair<iterator, iterator>             equal_range(const K& k); // C++20
162    template<typename K>
163        pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
164
165    size_type bucket_count() const noexcept;
166    size_type max_bucket_count() const noexcept;
167
168    size_type bucket_size(size_type n) const;
169    size_type bucket(const key_type& k) const;
170
171    local_iterator       begin(size_type n);
172    local_iterator       end(size_type n);
173    const_local_iterator begin(size_type n) const;
174    const_local_iterator end(size_type n) const;
175    const_local_iterator cbegin(size_type n) const;
176    const_local_iterator cend(size_type n) const;
177
178    float load_factor() const noexcept;
179    float max_load_factor() const noexcept;
180    void max_load_factor(float z);
181    void rehash(size_type n);
182    void reserve(size_type n);
183};
184
185template<class InputIterator,
186    class Hash = hash<typename iterator_traits<InputIterator>::value_type>,
187    class Pred = equal_to<typename iterator_traits<InputIterator>::value_type>,
188    class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
189unordered_set(InputIterator, InputIterator, typename see below::size_type = see below,
190    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
191  -> unordered_set<typename iterator_traits<InputIterator>::value_type,
192        Hash, Pred, Allocator>; // C++17
193
194template<class T, class Hash = hash<T>,
195          class Pred = equal_to<T>, class Allocator = allocator<T>>
196unordered_set(initializer_list<T>, typename see below::size_type = see below,
197    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
198  -> unordered_set<T, Hash, Pred, Allocator>; // C++17
199
200template<class InputIterator,  class Allocator>
201unordered_set(InputIterator, InputIterator, typename see below::size_type, Allocator)
202  -> unordered_set<typename iterator_traits<InputIterator>::value_type,
203        hash<typename iterator_traits<InputIterator>::value_type>,
204        equal_to<typename iterator_traits<InputIterator>::value_type>,
205        Allocator>; // C++17
206
207template<class InputIterator, class Hash, class Allocator>
208unordered_set(InputIterator, InputIterator, typename see below::size_type,
209    Hash, Allocator)
210  -> unordered_set<typename iterator_traits<InputIterator>::value_type, Hash,
211        equal_to<typename iterator_traits<InputIterator>::value_type>,
212        Allocator>; // C++17
213
214template<class T, class Allocator>
215unordered_set(initializer_list<T>, typename see below::size_type, Allocator)
216  -> unordered_set<T, hash<T>, equal_to<T>, Allocator>; // C++17
217
218template<class T, class Hash, class Allocator>
219unordered_set(initializer_list<T>, typename see below::size_type, Hash, Allocator)
220  -> unordered_set<T, Hash, equal_to<T>, Allocator>; // C++17
221
222template <class Value, class Hash, class Pred, class Alloc>
223    void swap(unordered_set<Value, Hash, Pred, Alloc>& x,
224              unordered_set<Value, Hash, Pred, Alloc>& y)
225              noexcept(noexcept(x.swap(y)));
226
227template <class Value, class Hash, class Pred, class Alloc>
228    bool
229    operator==(const unordered_set<Value, Hash, Pred, Alloc>& x,
230               const unordered_set<Value, Hash, Pred, Alloc>& y);
231
232template <class Value, class Hash, class Pred, class Alloc>
233    bool
234    operator!=(const unordered_set<Value, Hash, Pred, Alloc>& x,
235               const unordered_set<Value, Hash, Pred, Alloc>& y);
236
237template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
238          class Alloc = allocator<Value>>
239class unordered_multiset
240{
241public:
242    // types
243    typedef Value                                                      key_type;
244    typedef key_type                                                   value_type;
245    typedef Hash                                                       hasher;
246    typedef Pred                                                       key_equal;
247    typedef Alloc                                                      allocator_type;
248    typedef value_type&                                                reference;
249    typedef const value_type&                                          const_reference;
250    typedef typename allocator_traits<allocator_type>::pointer         pointer;
251    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
252    typedef typename allocator_traits<allocator_type>::size_type       size_type;
253    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
254
255    typedef /unspecified/ iterator;
256    typedef /unspecified/ const_iterator;
257    typedef /unspecified/ local_iterator;
258    typedef /unspecified/ const_local_iterator;
259
260    typedef unspecified node_type unspecified;   // C++17
261
262    unordered_multiset()
263        noexcept(
264            is_nothrow_default_constructible<hasher>::value &&
265            is_nothrow_default_constructible<key_equal>::value &&
266            is_nothrow_default_constructible<allocator_type>::value);
267    explicit unordered_multiset(size_type n, const hasher& hf = hasher(),
268                           const key_equal& eql = key_equal(),
269                           const allocator_type& a = allocator_type());
270    template <class InputIterator>
271        unordered_multiset(InputIterator f, InputIterator l,
272                      size_type n = 0, const hasher& hf = hasher(),
273                      const key_equal& eql = key_equal(),
274                      const allocator_type& a = allocator_type());
275    explicit unordered_multiset(const allocator_type&);
276    unordered_multiset(const unordered_multiset&);
277    unordered_multiset(const unordered_multiset&, const Allocator&);
278    unordered_multiset(unordered_multiset&&)
279        noexcept(
280            is_nothrow_move_constructible<hasher>::value &&
281            is_nothrow_move_constructible<key_equal>::value &&
282            is_nothrow_move_constructible<allocator_type>::value);
283    unordered_multiset(unordered_multiset&&, const Allocator&);
284    unordered_multiset(initializer_list<value_type>, size_type n = /see below/,
285                  const hasher& hf = hasher(), const key_equal& eql = key_equal(),
286                  const allocator_type& a = allocator_type());
287    unordered_multiset(size_type n, const allocator_type& a); // C++14
288    unordered_multiset(size_type n, const hasher& hf, const allocator_type& a); // C++14
289    template <class InputIterator>
290      unordered_multiset(InputIterator f, InputIterator l, size_type n, const allocator_type& a); // C++14
291    template <class InputIterator>
292      unordered_multiset(InputIterator f, InputIterator l, size_type n,
293                         const hasher& hf, const allocator_type& a); // C++14
294    unordered_multiset(initializer_list<value_type> il, size_type n, const allocator_type& a); // C++14
295    unordered_multiset(initializer_list<value_type> il, size_type n,
296                       const hasher& hf,  const allocator_type& a); // C++14
297    ~unordered_multiset();
298    unordered_multiset& operator=(const unordered_multiset&);
299    unordered_multiset& operator=(unordered_multiset&&)
300        noexcept(
301            allocator_type::propagate_on_container_move_assignment::value &&
302            is_nothrow_move_assignable<allocator_type>::value &&
303            is_nothrow_move_assignable<hasher>::value &&
304            is_nothrow_move_assignable<key_equal>::value);
305    unordered_multiset& operator=(initializer_list<value_type>);
306
307    allocator_type get_allocator() const noexcept;
308
309    bool      empty() const noexcept;
310    size_type size() const noexcept;
311    size_type max_size() const noexcept;
312
313    iterator       begin() noexcept;
314    iterator       end() noexcept;
315    const_iterator begin()  const noexcept;
316    const_iterator end()    const noexcept;
317    const_iterator cbegin() const noexcept;
318    const_iterator cend()   const noexcept;
319
320    template <class... Args>
321        iterator emplace(Args&&... args);
322    template <class... Args>
323        iterator emplace_hint(const_iterator position, Args&&... args);
324    iterator insert(const value_type& obj);
325    iterator insert(value_type&& obj);
326    iterator insert(const_iterator hint, const value_type& obj);
327    iterator insert(const_iterator hint, value_type&& obj);
328    template <class InputIterator>
329        void insert(InputIterator first, InputIterator last);
330    void insert(initializer_list<value_type>);
331
332    node_type extract(const_iterator position);             // C++17
333    node_type extract(const key_type& x);                   // C++17
334    iterator insert(node_type&& nh);                        // C++17
335    iterator insert(const_iterator hint, node_type&& nh);   // C++17
336
337    iterator erase(const_iterator position);
338    iterator erase(iterator position);  // C++14
339    size_type erase(const key_type& k);
340    iterator erase(const_iterator first, const_iterator last);
341    void clear() noexcept;
342
343    template<class H2, class P2>
344      void merge(unordered_multiset<Key, H2, P2, Allocator>& source);    // C++17
345    template<class H2, class P2>
346      void merge(unordered_multiset<Key, H2, P2, Allocator>&& source);   // C++17
347    template<class H2, class P2>
348      void merge(unordered_set<Key, H2, P2, Allocator>& source);         // C++17
349    template<class H2, class P2>
350      void merge(unordered_set<Key, H2, P2, Allocator>&& source);        // C++17
351
352    void swap(unordered_multiset&)
353       noexcept(allocator_traits<Allocator>::is_always_equal::value &&
354                 noexcept(swap(declval<hasher&>(), declval<hasher&>())) &&
355                 noexcept(swap(declval<key_equal&>(), declval<key_equal&>()))); // C++17
356
357    hasher hash_function() const;
358    key_equal key_eq() const;
359
360    iterator       find(const key_type& k);
361    const_iterator find(const key_type& k) const;
362    template<typename K>
363        iterator find(const K& x);              // C++20
364    template<typename K>
365        const_iterator find(const K& x) const;  // C++20
366    size_type count(const key_type& k) const;
367    template<typename K>
368        size_type count(const K& k) const; // C++20
369    bool contains(const key_type& k) const; // C++20
370    template<typename K>
371        bool contains(const K& k) const; // C++20
372    pair<iterator, iterator>             equal_range(const key_type& k);
373    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
374    template<typename K>
375        pair<iterator, iterator>             equal_range(const K& k); // C++20
376    template<typename K>
377        pair<const_iterator, const_iterator> equal_range(const K& k) const; // C++20
378
379    size_type bucket_count() const noexcept;
380    size_type max_bucket_count() const noexcept;
381
382    size_type bucket_size(size_type n) const;
383    size_type bucket(const key_type& k) const;
384
385    local_iterator       begin(size_type n);
386    local_iterator       end(size_type n);
387    const_local_iterator begin(size_type n) const;
388    const_local_iterator end(size_type n) const;
389    const_local_iterator cbegin(size_type n) const;
390    const_local_iterator cend(size_type n) const;
391
392    float load_factor() const noexcept;
393    float max_load_factor() const noexcept;
394    void max_load_factor(float z);
395    void rehash(size_type n);
396    void reserve(size_type n);
397};
398
399template<class InputIterator,
400    class Hash = hash<typename iterator_traits<InputIterator>::value_type>,
401    class Pred = equal_to<typename iterator_traits<InputIterator>::value_type>,
402    class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
403unordered_multiset(InputIterator, InputIterator, see below::size_type = see below,
404    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
405  -> unordered_multiset<typename iterator_traits<InputIterator>::value_type,
406        Hash, Pred, Allocator>; // C++17
407
408template<class T, class Hash = hash<T>,
409          class Pred = equal_to<T>, class Allocator = allocator<T>>
410unordered_multiset(initializer_list<T>, typename see below::size_type = see below,
411    Hash = Hash(), Pred = Pred(), Allocator = Allocator())
412  -> unordered_multiset<T, Hash, Pred, Allocator>; // C++17
413
414template<class InputIterator,  class Allocator>
415unordered_multiset(InputIterator, InputIterator, typename see below::size_type, Allocator)
416  -> unordered_multiset<typename iterator_traits<InputIterator>::value_type,
417        hash<typename iterator_traits<InputIterator>::value_type>,
418        equal_to<typename iterator_traits<InputIterator>::value_type>,
419        Allocator>; // C++17
420
421template<class InputIterator,  class Hash, class Allocator>
422unordered_multiset(InputIterator, InputIterator, typename see below::size_type,
423    Hash, Allocator)
424  -> unordered_multiset<typename iterator_traits<InputIterator>::value_type, Hash,
425        equal_to<typename iterator_traits<InputIterator>::value_type>, Allocator>; // C++17
426
427template<class T, class Allocator>
428unordered_multiset(initializer_list<T>, typename see below::size_type, Allocator)
429  -> unordered_multiset<T, hash<T>, equal_to<T>, Allocator>; // C++17
430
431template<class T, class Hash, class Allocator>
432unordered_multiset(initializer_list<T>, typename see below::size_type, Hash, Allocator)
433  -> unordered_multiset<T, Hash, equal_to<T>, Allocator>; // C++17
434
435template <class Value, class Hash, class Pred, class Alloc>
436    void swap(unordered_multiset<Value, Hash, Pred, Alloc>& x,
437              unordered_multiset<Value, Hash, Pred, Alloc>& y)
438              noexcept(noexcept(x.swap(y)));
439
440template <class K, class T, class H, class P, class A, class Predicate>
441    typename unordered_set<K, T, H, P, A>::size_type
442    erase_if(unordered_set<K, T, H, P, A>& c, Predicate pred);       // C++20
443
444template <class K, class T, class H, class P, class A, class Predicate>
445    typename unordered_multiset<K, T, H, P, A>::size_type
446    erase_if(unordered_multiset<K, T, H, P, A>& c, Predicate pred);  // C++20
447
448
449template <class Value, class Hash, class Pred, class Alloc>
450    bool
451    operator==(const unordered_multiset<Value, Hash, Pred, Alloc>& x,
452               const unordered_multiset<Value, Hash, Pred, Alloc>& y);
453
454template <class Value, class Hash, class Pred, class Alloc>
455    bool
456    operator!=(const unordered_multiset<Value, Hash, Pred, Alloc>& x,
457               const unordered_multiset<Value, Hash, Pred, Alloc>& y);
458}  // std
459
460*/
461
462#include <__algorithm/is_permutation.h>
463#include <__assert> // all public C++ headers provide the assertion handler
464#include <__config>
465#include <__debug>
466#include <__functional/is_transparent.h>
467#include <__functional/operations.h>
468#include <__hash_table>
469#include <__iterator/distance.h>
470#include <__iterator/erase_if_container.h>
471#include <__iterator/iterator_traits.h>
472#include <__memory/addressof.h>
473#include <__node_handle>
474#include <__utility/forward.h>
475#include <version>
476
477#ifndef _LIBCPP_REMOVE_TRANSITIVE_INCLUDES
478#  include <functional>
479#  include <iterator>
480#endif
481
482// standard-mandated includes
483
484// [iterator.range]
485#include <__iterator/access.h>
486#include <__iterator/data.h>
487#include <__iterator/empty.h>
488#include <__iterator/reverse_access.h>
489#include <__iterator/size.h>
490
491// [unord.set.syn]
492#include <compare>
493#include <initializer_list>
494
495#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
496#  pragma GCC system_header
497#endif
498
499_LIBCPP_BEGIN_NAMESPACE_STD
500
501template <class _Value, class _Hash, class _Pred, class _Alloc>
502class unordered_multiset;
503
504template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>,
505          class _Alloc = allocator<_Value> >
506class _LIBCPP_TEMPLATE_VIS unordered_set
507{
508public:
509    // types
510    typedef _Value                                                     key_type;
511    typedef key_type                                                   value_type;
512    typedef __type_identity_t<_Hash>                                   hasher;
513    typedef __type_identity_t<_Pred>                                   key_equal;
514    typedef __type_identity_t<_Alloc>                                  allocator_type;
515    typedef value_type&                                                reference;
516    typedef const value_type&                                          const_reference;
517    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
518                  "Invalid allocator::value_type");
519
520private:
521    typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
522
523    __table __table_;
524
525public:
526    typedef typename __table::pointer         pointer;
527    typedef typename __table::const_pointer   const_pointer;
528    typedef typename __table::size_type       size_type;
529    typedef typename __table::difference_type difference_type;
530
531    typedef typename __table::const_iterator       iterator;
532    typedef typename __table::const_iterator       const_iterator;
533    typedef typename __table::const_local_iterator local_iterator;
534    typedef typename __table::const_local_iterator const_local_iterator;
535
536#if _LIBCPP_STD_VER > 14
537    typedef __set_node_handle<typename __table::__node, allocator_type> node_type;
538    typedef __insert_return_type<iterator, node_type> insert_return_type;
539#endif
540
541    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
542        friend class _LIBCPP_TEMPLATE_VIS unordered_set;
543    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
544        friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
545
546    _LIBCPP_INLINE_VISIBILITY
547    unordered_set()
548        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
549    {
550        _VSTD::__debug_db_insert_c(this);
551    }
552    explicit unordered_set(size_type __n, const hasher& __hf = hasher(),
553                           const key_equal& __eql = key_equal());
554#if _LIBCPP_STD_VER > 11
555    inline _LIBCPP_INLINE_VISIBILITY
556    unordered_set(size_type __n, const allocator_type& __a)
557        : unordered_set(__n, hasher(), key_equal(), __a) {}
558    inline _LIBCPP_INLINE_VISIBILITY
559    unordered_set(size_type __n, const hasher& __hf, const allocator_type& __a)
560        : unordered_set(__n, __hf, key_equal(), __a) {}
561#endif
562    unordered_set(size_type __n, const hasher& __hf, const key_equal& __eql,
563                  const allocator_type& __a);
564    template <class _InputIterator>
565        unordered_set(_InputIterator __first, _InputIterator __last);
566    template <class _InputIterator>
567        unordered_set(_InputIterator __first, _InputIterator __last,
568                      size_type __n, const hasher& __hf = hasher(),
569                      const key_equal& __eql = key_equal());
570    template <class _InputIterator>
571        unordered_set(_InputIterator __first, _InputIterator __last,
572                      size_type __n, const hasher& __hf, const key_equal& __eql,
573                      const allocator_type& __a);
574#if _LIBCPP_STD_VER > 11
575    template <class _InputIterator>
576    inline _LIBCPP_INLINE_VISIBILITY
577        unordered_set(_InputIterator __first, _InputIterator __last,
578                    size_type __n, const allocator_type& __a)
579            : unordered_set(__first, __last, __n, hasher(), key_equal(), __a) {}
580    template <class _InputIterator>
581        unordered_set(_InputIterator __first, _InputIterator __last,
582                      size_type __n, const hasher& __hf, const allocator_type& __a)
583            : unordered_set(__first, __last, __n, __hf, key_equal(), __a) {}
584#endif
585    _LIBCPP_INLINE_VISIBILITY
586    explicit unordered_set(const allocator_type& __a);
587    unordered_set(const unordered_set& __u);
588    unordered_set(const unordered_set& __u, const allocator_type& __a);
589#ifndef _LIBCPP_CXX03_LANG
590    _LIBCPP_INLINE_VISIBILITY
591    unordered_set(unordered_set&& __u)
592        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
593    unordered_set(unordered_set&& __u, const allocator_type& __a);
594    unordered_set(initializer_list<value_type> __il);
595    unordered_set(initializer_list<value_type> __il, size_type __n,
596                  const hasher& __hf = hasher(),
597                  const key_equal& __eql = key_equal());
598    unordered_set(initializer_list<value_type> __il, size_type __n,
599                  const hasher& __hf, const key_equal& __eql,
600                  const allocator_type& __a);
601#if _LIBCPP_STD_VER > 11
602    inline _LIBCPP_INLINE_VISIBILITY
603    unordered_set(initializer_list<value_type> __il, size_type __n,
604                                                      const allocator_type& __a)
605        : unordered_set(__il, __n, hasher(), key_equal(), __a) {}
606    inline _LIBCPP_INLINE_VISIBILITY
607    unordered_set(initializer_list<value_type> __il, size_type __n,
608                                  const hasher& __hf, const allocator_type& __a)
609        : unordered_set(__il, __n, __hf, key_equal(), __a) {}
610#endif
611#endif // _LIBCPP_CXX03_LANG
612    _LIBCPP_INLINE_VISIBILITY
613    ~unordered_set() {
614        static_assert(sizeof(__diagnose_unordered_container_requirements<_Value, _Hash, _Pred>(0)), "");
615    }
616
617    _LIBCPP_INLINE_VISIBILITY
618    unordered_set& operator=(const unordered_set& __u)
619    {
620        __table_ = __u.__table_;
621        return *this;
622    }
623#ifndef _LIBCPP_CXX03_LANG
624    _LIBCPP_INLINE_VISIBILITY
625    unordered_set& operator=(unordered_set&& __u)
626        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
627    _LIBCPP_INLINE_VISIBILITY
628    unordered_set& operator=(initializer_list<value_type> __il);
629#endif // _LIBCPP_CXX03_LANG
630
631    _LIBCPP_INLINE_VISIBILITY
632    allocator_type get_allocator() const _NOEXCEPT
633        {return allocator_type(__table_.__node_alloc());}
634
635    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
636    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
637    _LIBCPP_INLINE_VISIBILITY
638    size_type size() const _NOEXCEPT  {return __table_.size();}
639    _LIBCPP_INLINE_VISIBILITY
640    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
641
642    _LIBCPP_INLINE_VISIBILITY
643    iterator       begin() _NOEXCEPT        {return __table_.begin();}
644    _LIBCPP_INLINE_VISIBILITY
645    iterator       end() _NOEXCEPT          {return __table_.end();}
646    _LIBCPP_INLINE_VISIBILITY
647    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
648    _LIBCPP_INLINE_VISIBILITY
649    const_iterator end()    const _NOEXCEPT {return __table_.end();}
650    _LIBCPP_INLINE_VISIBILITY
651    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
652    _LIBCPP_INLINE_VISIBILITY
653    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
654
655#ifndef _LIBCPP_CXX03_LANG
656    template <class... _Args>
657        _LIBCPP_INLINE_VISIBILITY
658        pair<iterator, bool> emplace(_Args&&... __args)
659            {return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...);}
660    template <class... _Args>
661    _LIBCPP_INLINE_VISIBILITY
662    iterator emplace_hint(const_iterator __p, _Args&&... __args) {
663        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__p)) == this,
664            "unordered_set::emplace_hint(const_iterator, args...) called with an iterator not"
665            " referring to this unordered_set");
666        (void)__p;
667        return __table_.__emplace_unique(std::forward<_Args>(__args)...).first;
668    }
669
670    _LIBCPP_INLINE_VISIBILITY
671    pair<iterator, bool> insert(value_type&& __x)
672        {return __table_.__insert_unique(_VSTD::move(__x));}
673    _LIBCPP_INLINE_VISIBILITY
674    iterator insert(const_iterator __p, value_type&& __x) {
675        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__p)) == this,
676            "unordered_set::insert(const_iterator, value_type&&) called with an iterator not"
677            " referring to this unordered_set");
678        (void)__p;
679        return insert(std::move(__x)).first;
680    }
681
682    _LIBCPP_INLINE_VISIBILITY
683    void insert(initializer_list<value_type> __il)
684        {insert(__il.begin(), __il.end());}
685#endif // _LIBCPP_CXX03_LANG
686    _LIBCPP_INLINE_VISIBILITY
687    pair<iterator, bool> insert(const value_type& __x)
688        {return __table_.__insert_unique(__x);}
689
690    _LIBCPP_INLINE_VISIBILITY
691    iterator insert(const_iterator __p, const value_type& __x) {
692        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__p)) == this,
693            "unordered_set::insert(const_iterator, const value_type&) called with an iterator not"
694            " referring to this unordered_set");
695        (void)__p;
696        return insert(__x).first;
697    }
698    template <class _InputIterator>
699        _LIBCPP_INLINE_VISIBILITY
700        void insert(_InputIterator __first, _InputIterator __last);
701
702    _LIBCPP_INLINE_VISIBILITY
703    iterator erase(const_iterator __p) {return __table_.erase(__p);}
704    _LIBCPP_INLINE_VISIBILITY
705    size_type erase(const key_type& __k) {return __table_.__erase_unique(__k);}
706    _LIBCPP_INLINE_VISIBILITY
707    iterator erase(const_iterator __first, const_iterator __last)
708        {return __table_.erase(__first, __last);}
709    _LIBCPP_INLINE_VISIBILITY
710    void clear() _NOEXCEPT {__table_.clear();}
711
712#if _LIBCPP_STD_VER > 14
713    _LIBCPP_INLINE_VISIBILITY
714    insert_return_type insert(node_type&& __nh)
715    {
716        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
717            "node_type with incompatible allocator passed to unordered_set::insert()");
718        return __table_.template __node_handle_insert_unique<
719            node_type, insert_return_type>(_VSTD::move(__nh));
720    }
721    _LIBCPP_INLINE_VISIBILITY
722    iterator insert(const_iterator __h, node_type&& __nh)
723    {
724        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
725            "node_type with incompatible allocator passed to unordered_set::insert()");
726        return __table_.template __node_handle_insert_unique<node_type>(
727            __h, _VSTD::move(__nh));
728    }
729    _LIBCPP_INLINE_VISIBILITY
730    node_type extract(key_type const& __key)
731    {
732        return __table_.template __node_handle_extract<node_type>(__key);
733    }
734    _LIBCPP_INLINE_VISIBILITY
735    node_type extract(const_iterator __it)
736    {
737        return __table_.template __node_handle_extract<node_type>(__it);
738    }
739
740    template<class _H2, class _P2>
741    _LIBCPP_INLINE_VISIBILITY
742    void merge(unordered_set<key_type, _H2, _P2, allocator_type>& __source)
743    {
744        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
745                       "merging container with incompatible allocator");
746        __table_.__node_handle_merge_unique(__source.__table_);
747    }
748    template<class _H2, class _P2>
749    _LIBCPP_INLINE_VISIBILITY
750    void merge(unordered_set<key_type, _H2, _P2, allocator_type>&& __source)
751    {
752        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
753                       "merging container with incompatible allocator");
754        __table_.__node_handle_merge_unique(__source.__table_);
755    }
756    template<class _H2, class _P2>
757    _LIBCPP_INLINE_VISIBILITY
758    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>& __source)
759    {
760        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
761                       "merging container with incompatible allocator");
762        __table_.__node_handle_merge_unique(__source.__table_);
763    }
764    template<class _H2, class _P2>
765    _LIBCPP_INLINE_VISIBILITY
766    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>&& __source)
767    {
768        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
769                       "merging container with incompatible allocator");
770        __table_.__node_handle_merge_unique(__source.__table_);
771    }
772#endif
773
774    _LIBCPP_INLINE_VISIBILITY
775    void swap(unordered_set& __u)
776        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
777        {__table_.swap(__u.__table_);}
778
779    _LIBCPP_INLINE_VISIBILITY
780    hasher hash_function() const {return __table_.hash_function();}
781    _LIBCPP_INLINE_VISIBILITY
782    key_equal key_eq() const {return __table_.key_eq();}
783
784    _LIBCPP_INLINE_VISIBILITY
785    iterator       find(const key_type& __k)       {return __table_.find(__k);}
786    _LIBCPP_INLINE_VISIBILITY
787    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
788#if _LIBCPP_STD_VER > 17
789    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
790    _LIBCPP_INLINE_VISIBILITY
791    iterator       find(const _K2& __k)            {return __table_.find(__k);}
792    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
793    _LIBCPP_INLINE_VISIBILITY
794    const_iterator find(const _K2& __k) const      {return __table_.find(__k);}
795#endif // _LIBCPP_STD_VER > 17
796
797    _LIBCPP_INLINE_VISIBILITY
798    size_type count(const key_type& __k) const {return __table_.__count_unique(__k);}
799#if _LIBCPP_STD_VER > 17
800    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
801    _LIBCPP_INLINE_VISIBILITY
802    size_type count(const _K2& __k) const      {return __table_.__count_unique(__k);}
803#endif // _LIBCPP_STD_VER > 17
804
805#if _LIBCPP_STD_VER > 17
806    _LIBCPP_INLINE_VISIBILITY
807    bool contains(const key_type& __k) const {return find(__k) != end();}
808
809    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
810    _LIBCPP_INLINE_VISIBILITY
811    bool contains(const _K2& __k) const      {return find(__k) != end();}
812#endif // _LIBCPP_STD_VER > 17
813
814    _LIBCPP_INLINE_VISIBILITY
815    pair<iterator, iterator>             equal_range(const key_type& __k)
816        {return __table_.__equal_range_unique(__k);}
817    _LIBCPP_INLINE_VISIBILITY
818    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
819        {return __table_.__equal_range_unique(__k);}
820#if _LIBCPP_STD_VER > 17
821    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
822    _LIBCPP_INLINE_VISIBILITY
823    pair<iterator, iterator>             equal_range(const _K2& __k)
824        {return __table_.__equal_range_unique(__k);}
825    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
826    _LIBCPP_INLINE_VISIBILITY
827    pair<const_iterator, const_iterator> equal_range(const _K2& __k) const
828        {return __table_.__equal_range_unique(__k);}
829#endif // _LIBCPP_STD_VER > 17
830
831    _LIBCPP_INLINE_VISIBILITY
832    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
833    _LIBCPP_INLINE_VISIBILITY
834    size_type max_bucket_count() const _NOEXCEPT {return __table_.max_bucket_count();}
835
836    _LIBCPP_INLINE_VISIBILITY
837    size_type bucket_size(size_type __n) const {return __table_.bucket_size(__n);}
838    _LIBCPP_INLINE_VISIBILITY
839    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
840
841    _LIBCPP_INLINE_VISIBILITY
842    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
843    _LIBCPP_INLINE_VISIBILITY
844    local_iterator       end(size_type __n)          {return __table_.end(__n);}
845    _LIBCPP_INLINE_VISIBILITY
846    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
847    _LIBCPP_INLINE_VISIBILITY
848    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
849    _LIBCPP_INLINE_VISIBILITY
850    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
851    _LIBCPP_INLINE_VISIBILITY
852    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
853
854    _LIBCPP_INLINE_VISIBILITY
855    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
856    _LIBCPP_INLINE_VISIBILITY
857    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
858    _LIBCPP_INLINE_VISIBILITY
859    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
860    _LIBCPP_INLINE_VISIBILITY
861    void rehash(size_type __n) {__table_.__rehash_unique(__n);}
862    _LIBCPP_INLINE_VISIBILITY
863    void reserve(size_type __n) {__table_.__reserve_unique(__n);}
864
865#ifdef _LIBCPP_ENABLE_DEBUG_MODE
866
867    bool __dereferenceable(const const_iterator* __i) const
868        {return __table_.__dereferenceable(__i);}
869    bool __decrementable(const const_iterator* __i) const
870        {return __table_.__decrementable(__i);}
871    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
872        {return __table_.__addable(__i, __n);}
873    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
874        {return __table_.__addable(__i, __n);}
875
876#endif // _LIBCPP_ENABLE_DEBUG_MODE
877
878};
879
880#if _LIBCPP_STD_VER >= 17
881template<class _InputIterator,
882         class _Hash = hash<__iter_value_type<_InputIterator>>,
883         class _Pred = equal_to<__iter_value_type<_InputIterator>>,
884         class _Allocator = allocator<__iter_value_type<_InputIterator>>,
885         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
886         class = enable_if_t<!__is_allocator<_Hash>::value>,
887         class = enable_if_t<!is_integral<_Hash>::value>,
888         class = enable_if_t<!__is_allocator<_Pred>::value>,
889         class = enable_if_t<__is_allocator<_Allocator>::value>>
890unordered_set(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
891              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
892  -> unordered_set<__iter_value_type<_InputIterator>, _Hash, _Pred, _Allocator>;
893
894template<class _Tp, class _Hash = hash<_Tp>,
895         class _Pred = equal_to<_Tp>,
896         class _Allocator = allocator<_Tp>,
897         class = enable_if_t<!__is_allocator<_Hash>::value>,
898         class = enable_if_t<!is_integral<_Hash>::value>,
899         class = enable_if_t<!__is_allocator<_Pred>::value>,
900         class = enable_if_t<__is_allocator<_Allocator>::value>>
901unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type = 0,
902              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
903  -> unordered_set<_Tp, _Hash, _Pred, _Allocator>;
904
905template<class _InputIterator, class _Allocator,
906         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
907         class = enable_if_t<__is_allocator<_Allocator>::value>>
908unordered_set(_InputIterator, _InputIterator,
909              typename allocator_traits<_Allocator>::size_type, _Allocator)
910  -> unordered_set<__iter_value_type<_InputIterator>,
911                   hash<__iter_value_type<_InputIterator>>,
912                   equal_to<__iter_value_type<_InputIterator>>,
913                   _Allocator>;
914
915template<class _InputIterator, class _Hash, class _Allocator,
916         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
917         class = enable_if_t<!__is_allocator<_Hash>::value>,
918         class = enable_if_t<!is_integral<_Hash>::value>,
919         class = enable_if_t<__is_allocator<_Allocator>::value>>
920unordered_set(_InputIterator, _InputIterator,
921              typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
922  -> unordered_set<__iter_value_type<_InputIterator>, _Hash,
923                   equal_to<__iter_value_type<_InputIterator>>,
924                   _Allocator>;
925
926template<class _Tp, class _Allocator,
927         class = enable_if_t<__is_allocator<_Allocator>::value>>
928unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Allocator)
929  -> unordered_set<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
930
931template<class _Tp, class _Hash, class _Allocator,
932         class = enable_if_t<!__is_allocator<_Hash>::value>,
933         class = enable_if_t<!is_integral<_Hash>::value>,
934         class = enable_if_t<__is_allocator<_Allocator>::value>>
935unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
936  -> unordered_set<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
937#endif
938
939template <class _Value, class _Hash, class _Pred, class _Alloc>
940unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(size_type __n,
941        const hasher& __hf, const key_equal& __eql)
942    : __table_(__hf, __eql)
943{
944    _VSTD::__debug_db_insert_c(this);
945    __table_.__rehash_unique(__n);
946}
947
948template <class _Value, class _Hash, class _Pred, class _Alloc>
949unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(size_type __n,
950        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
951    : __table_(__hf, __eql, __a)
952{
953    _VSTD::__debug_db_insert_c(this);
954    __table_.__rehash_unique(__n);
955}
956
957template <class _Value, class _Hash, class _Pred, class _Alloc>
958template <class _InputIterator>
959unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
960        _InputIterator __first, _InputIterator __last)
961{
962    _VSTD::__debug_db_insert_c(this);
963    insert(__first, __last);
964}
965
966template <class _Value, class _Hash, class _Pred, class _Alloc>
967template <class _InputIterator>
968unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
969        _InputIterator __first, _InputIterator __last, size_type __n,
970        const hasher& __hf, const key_equal& __eql)
971    : __table_(__hf, __eql)
972{
973    _VSTD::__debug_db_insert_c(this);
974    __table_.__rehash_unique(__n);
975    insert(__first, __last);
976}
977
978template <class _Value, class _Hash, class _Pred, class _Alloc>
979template <class _InputIterator>
980unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
981        _InputIterator __first, _InputIterator __last, size_type __n,
982        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
983    : __table_(__hf, __eql, __a)
984{
985    _VSTD::__debug_db_insert_c(this);
986    __table_.__rehash_unique(__n);
987    insert(__first, __last);
988}
989
990template <class _Value, class _Hash, class _Pred, class _Alloc>
991inline
992unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
993        const allocator_type& __a)
994    : __table_(__a)
995{
996    _VSTD::__debug_db_insert_c(this);
997}
998
999template <class _Value, class _Hash, class _Pred, class _Alloc>
1000unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1001        const unordered_set& __u)
1002    : __table_(__u.__table_)
1003{
1004    _VSTD::__debug_db_insert_c(this);
1005    __table_.__rehash_unique(__u.bucket_count());
1006    insert(__u.begin(), __u.end());
1007}
1008
1009template <class _Value, class _Hash, class _Pred, class _Alloc>
1010unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1011        const unordered_set& __u, const allocator_type& __a)
1012    : __table_(__u.__table_, __a)
1013{
1014    _VSTD::__debug_db_insert_c(this);
1015    __table_.__rehash_unique(__u.bucket_count());
1016    insert(__u.begin(), __u.end());
1017}
1018
1019#ifndef _LIBCPP_CXX03_LANG
1020
1021template <class _Value, class _Hash, class _Pred, class _Alloc>
1022inline
1023unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1024        unordered_set&& __u)
1025    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
1026    : __table_(_VSTD::move(__u.__table_))
1027{
1028    _VSTD::__debug_db_insert_c(this);
1029    std::__debug_db_swap(this, std::addressof(__u));
1030}
1031
1032template <class _Value, class _Hash, class _Pred, class _Alloc>
1033unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1034        unordered_set&& __u, const allocator_type& __a)
1035    : __table_(_VSTD::move(__u.__table_), __a)
1036{
1037    _VSTD::__debug_db_insert_c(this);
1038    if (__a != __u.get_allocator())
1039    {
1040        iterator __i = __u.begin();
1041        while (__u.size() != 0)
1042            __table_.__insert_unique(_VSTD::move(__u.__table_.remove(__i++)->__value_));
1043    }
1044    else
1045        std::__debug_db_swap(this, std::addressof(__u));
1046}
1047
1048template <class _Value, class _Hash, class _Pred, class _Alloc>
1049unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1050        initializer_list<value_type> __il)
1051{
1052    _VSTD::__debug_db_insert_c(this);
1053    insert(__il.begin(), __il.end());
1054}
1055
1056template <class _Value, class _Hash, class _Pred, class _Alloc>
1057unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1058        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1059        const key_equal& __eql)
1060    : __table_(__hf, __eql)
1061{
1062    _VSTD::__debug_db_insert_c(this);
1063    __table_.__rehash_unique(__n);
1064    insert(__il.begin(), __il.end());
1065}
1066
1067template <class _Value, class _Hash, class _Pred, class _Alloc>
1068unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1069        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1070        const key_equal& __eql, const allocator_type& __a)
1071    : __table_(__hf, __eql, __a)
1072{
1073    _VSTD::__debug_db_insert_c(this);
1074    __table_.__rehash_unique(__n);
1075    insert(__il.begin(), __il.end());
1076}
1077
1078template <class _Value, class _Hash, class _Pred, class _Alloc>
1079inline
1080unordered_set<_Value, _Hash, _Pred, _Alloc>&
1081unordered_set<_Value, _Hash, _Pred, _Alloc>::operator=(unordered_set&& __u)
1082    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
1083{
1084    __table_ = _VSTD::move(__u.__table_);
1085    return *this;
1086}
1087
1088template <class _Value, class _Hash, class _Pred, class _Alloc>
1089inline
1090unordered_set<_Value, _Hash, _Pred, _Alloc>&
1091unordered_set<_Value, _Hash, _Pred, _Alloc>::operator=(
1092        initializer_list<value_type> __il)
1093{
1094    __table_.__assign_unique(__il.begin(), __il.end());
1095    return *this;
1096}
1097
1098#endif // _LIBCPP_CXX03_LANG
1099
1100template <class _Value, class _Hash, class _Pred, class _Alloc>
1101template <class _InputIterator>
1102inline
1103void
1104unordered_set<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
1105                                                    _InputIterator __last)
1106{
1107    for (; __first != __last; ++__first)
1108        __table_.__insert_unique(*__first);
1109}
1110
1111template <class _Value, class _Hash, class _Pred, class _Alloc>
1112inline _LIBCPP_INLINE_VISIBILITY
1113void
1114swap(unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
1115     unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
1116    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1117{
1118    __x.swap(__y);
1119}
1120
1121#if _LIBCPP_STD_VER > 17
1122template <class _Value, class _Hash, class _Pred, class _Alloc,
1123          class _Predicate>
1124inline _LIBCPP_INLINE_VISIBILITY
1125    typename unordered_set<_Value, _Hash, _Pred, _Alloc>::size_type
1126    erase_if(unordered_set<_Value, _Hash, _Pred, _Alloc>& __c,
1127             _Predicate __pred) {
1128  return _VSTD::__libcpp_erase_if_container(__c, __pred);
1129}
1130#endif
1131
1132template <class _Value, class _Hash, class _Pred, class _Alloc>
1133bool
1134operator==(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
1135           const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
1136{
1137    if (__x.size() != __y.size())
1138        return false;
1139    typedef typename unordered_set<_Value, _Hash, _Pred, _Alloc>::const_iterator
1140                                                                 const_iterator;
1141    for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end();
1142            __i != __ex; ++__i)
1143    {
1144        const_iterator __j = __y.find(*__i);
1145        if (__j == __ey || !(*__i == *__j))
1146            return false;
1147    }
1148    return true;
1149}
1150
1151template <class _Value, class _Hash, class _Pred, class _Alloc>
1152inline _LIBCPP_INLINE_VISIBILITY
1153bool
1154operator!=(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
1155           const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
1156{
1157    return !(__x == __y);
1158}
1159
1160template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>,
1161          class _Alloc = allocator<_Value> >
1162class _LIBCPP_TEMPLATE_VIS unordered_multiset
1163{
1164public:
1165    // types
1166    typedef _Value                                                     key_type;
1167    typedef key_type                                                   value_type;
1168    typedef __type_identity_t<_Hash>                                   hasher;
1169    typedef __type_identity_t<_Pred>                                   key_equal;
1170    typedef __type_identity_t<_Alloc>                                  allocator_type;
1171    typedef value_type&                                                reference;
1172    typedef const value_type&                                          const_reference;
1173    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
1174                  "Invalid allocator::value_type");
1175
1176private:
1177    typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
1178
1179    __table __table_;
1180
1181public:
1182    typedef typename __table::pointer         pointer;
1183    typedef typename __table::const_pointer   const_pointer;
1184    typedef typename __table::size_type       size_type;
1185    typedef typename __table::difference_type difference_type;
1186
1187    typedef typename __table::const_iterator       iterator;
1188    typedef typename __table::const_iterator       const_iterator;
1189    typedef typename __table::const_local_iterator local_iterator;
1190    typedef typename __table::const_local_iterator const_local_iterator;
1191
1192#if _LIBCPP_STD_VER > 14
1193    typedef __set_node_handle<typename __table::__node, allocator_type> node_type;
1194#endif
1195
1196    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
1197        friend class _LIBCPP_TEMPLATE_VIS unordered_set;
1198    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
1199        friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
1200
1201    _LIBCPP_INLINE_VISIBILITY
1202    unordered_multiset()
1203        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
1204    {
1205        _VSTD::__debug_db_insert_c(this);
1206    }
1207    explicit unordered_multiset(size_type __n, const hasher& __hf = hasher(),
1208                                const key_equal& __eql = key_equal());
1209    unordered_multiset(size_type __n, const hasher& __hf,
1210                       const key_equal& __eql, const allocator_type& __a);
1211#if _LIBCPP_STD_VER > 11
1212    inline _LIBCPP_INLINE_VISIBILITY
1213    unordered_multiset(size_type __n, const allocator_type& __a)
1214        : unordered_multiset(__n, hasher(), key_equal(), __a) {}
1215    inline _LIBCPP_INLINE_VISIBILITY
1216    unordered_multiset(size_type __n, const hasher& __hf, const allocator_type& __a)
1217        : unordered_multiset(__n, __hf, key_equal(), __a) {}
1218#endif
1219    template <class _InputIterator>
1220        unordered_multiset(_InputIterator __first, _InputIterator __last);
1221    template <class _InputIterator>
1222        unordered_multiset(_InputIterator __first, _InputIterator __last,
1223                      size_type __n, const hasher& __hf = hasher(),
1224                      const key_equal& __eql = key_equal());
1225    template <class _InputIterator>
1226        unordered_multiset(_InputIterator __first, _InputIterator __last,
1227                      size_type __n , const hasher& __hf,
1228                      const key_equal& __eql, const allocator_type& __a);
1229#if _LIBCPP_STD_VER > 11
1230    template <class _InputIterator>
1231    inline _LIBCPP_INLINE_VISIBILITY
1232    unordered_multiset(_InputIterator __first, _InputIterator __last,
1233                       size_type __n, const allocator_type& __a)
1234        : unordered_multiset(__first, __last, __n, hasher(), key_equal(), __a) {}
1235    template <class _InputIterator>
1236    inline _LIBCPP_INLINE_VISIBILITY
1237    unordered_multiset(_InputIterator __first, _InputIterator __last,
1238                       size_type __n, const hasher& __hf, const allocator_type& __a)
1239        : unordered_multiset(__first, __last, __n, __hf, key_equal(), __a) {}
1240#endif
1241    _LIBCPP_INLINE_VISIBILITY
1242    explicit unordered_multiset(const allocator_type& __a);
1243    unordered_multiset(const unordered_multiset& __u);
1244    unordered_multiset(const unordered_multiset& __u, const allocator_type& __a);
1245#ifndef _LIBCPP_CXX03_LANG
1246    _LIBCPP_INLINE_VISIBILITY
1247    unordered_multiset(unordered_multiset&& __u)
1248        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
1249    unordered_multiset(unordered_multiset&& __u, const allocator_type& __a);
1250    unordered_multiset(initializer_list<value_type> __il);
1251    unordered_multiset(initializer_list<value_type> __il, size_type __n,
1252                       const hasher& __hf = hasher(),
1253                       const key_equal& __eql = key_equal());
1254    unordered_multiset(initializer_list<value_type> __il, size_type __n,
1255                       const hasher& __hf, const key_equal& __eql,
1256                       const allocator_type& __a);
1257#if _LIBCPP_STD_VER > 11
1258    inline _LIBCPP_INLINE_VISIBILITY
1259    unordered_multiset(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
1260      : unordered_multiset(__il, __n, hasher(), key_equal(), __a) {}
1261    inline _LIBCPP_INLINE_VISIBILITY
1262    unordered_multiset(initializer_list<value_type> __il, size_type __n, const hasher& __hf, const allocator_type& __a)
1263      : unordered_multiset(__il, __n, __hf, key_equal(), __a) {}
1264#endif
1265#endif // _LIBCPP_CXX03_LANG
1266    _LIBCPP_INLINE_VISIBILITY
1267    ~unordered_multiset() {
1268        static_assert(sizeof(__diagnose_unordered_container_requirements<_Value, _Hash, _Pred>(0)), "");
1269    }
1270
1271    _LIBCPP_INLINE_VISIBILITY
1272    unordered_multiset& operator=(const unordered_multiset& __u)
1273    {
1274        __table_ = __u.__table_;
1275        return *this;
1276    }
1277#ifndef _LIBCPP_CXX03_LANG
1278    _LIBCPP_INLINE_VISIBILITY
1279    unordered_multiset& operator=(unordered_multiset&& __u)
1280        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
1281    unordered_multiset& operator=(initializer_list<value_type> __il);
1282#endif // _LIBCPP_CXX03_LANG
1283
1284    _LIBCPP_INLINE_VISIBILITY
1285    allocator_type get_allocator() const _NOEXCEPT
1286        {return allocator_type(__table_.__node_alloc());}
1287
1288    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1289    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
1290    _LIBCPP_INLINE_VISIBILITY
1291    size_type size() const _NOEXCEPT  {return __table_.size();}
1292    _LIBCPP_INLINE_VISIBILITY
1293    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
1294
1295    _LIBCPP_INLINE_VISIBILITY
1296    iterator       begin() _NOEXCEPT        {return __table_.begin();}
1297    _LIBCPP_INLINE_VISIBILITY
1298    iterator       end() _NOEXCEPT          {return __table_.end();}
1299    _LIBCPP_INLINE_VISIBILITY
1300    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
1301    _LIBCPP_INLINE_VISIBILITY
1302    const_iterator end()    const _NOEXCEPT {return __table_.end();}
1303    _LIBCPP_INLINE_VISIBILITY
1304    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
1305    _LIBCPP_INLINE_VISIBILITY
1306    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
1307
1308#ifndef _LIBCPP_CXX03_LANG
1309    template <class... _Args>
1310        _LIBCPP_INLINE_VISIBILITY
1311        iterator emplace(_Args&&... __args)
1312            {return __table_.__emplace_multi(_VSTD::forward<_Args>(__args)...);}
1313    template <class... _Args>
1314        _LIBCPP_INLINE_VISIBILITY
1315        iterator emplace_hint(const_iterator __p, _Args&&... __args)
1316            {return __table_.__emplace_hint_multi(__p, _VSTD::forward<_Args>(__args)...);}
1317
1318    _LIBCPP_INLINE_VISIBILITY
1319    iterator insert(value_type&& __x) {return __table_.__insert_multi(_VSTD::move(__x));}
1320    _LIBCPP_INLINE_VISIBILITY
1321    iterator insert(const_iterator __p, value_type&& __x)
1322        {return __table_.__insert_multi(__p, _VSTD::move(__x));}
1323    _LIBCPP_INLINE_VISIBILITY
1324    void insert(initializer_list<value_type> __il)
1325        {insert(__il.begin(), __il.end());}
1326#endif // _LIBCPP_CXX03_LANG
1327
1328    _LIBCPP_INLINE_VISIBILITY
1329    iterator insert(const value_type& __x) {return __table_.__insert_multi(__x);}
1330
1331    _LIBCPP_INLINE_VISIBILITY
1332    iterator insert(const_iterator __p, const value_type& __x)
1333        {return __table_.__insert_multi(__p, __x);}
1334
1335    template <class _InputIterator>
1336        _LIBCPP_INLINE_VISIBILITY
1337        void insert(_InputIterator __first, _InputIterator __last);
1338
1339#if _LIBCPP_STD_VER > 14
1340    _LIBCPP_INLINE_VISIBILITY
1341    iterator insert(node_type&& __nh)
1342    {
1343        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1344            "node_type with incompatible allocator passed to unordered_multiset::insert()");
1345        return __table_.template __node_handle_insert_multi<node_type>(
1346            _VSTD::move(__nh));
1347    }
1348    _LIBCPP_INLINE_VISIBILITY
1349    iterator insert(const_iterator __hint, node_type&& __nh)
1350    {
1351        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1352            "node_type with incompatible allocator passed to unordered_multiset::insert()");
1353        return __table_.template __node_handle_insert_multi<node_type>(
1354            __hint, _VSTD::move(__nh));
1355    }
1356    _LIBCPP_INLINE_VISIBILITY
1357    node_type extract(const_iterator __position)
1358    {
1359        return __table_.template __node_handle_extract<node_type>(
1360            __position);
1361    }
1362    _LIBCPP_INLINE_VISIBILITY
1363    node_type extract(key_type const& __key)
1364    {
1365        return __table_.template __node_handle_extract<node_type>(__key);
1366    }
1367
1368    template <class _H2, class _P2>
1369    _LIBCPP_INLINE_VISIBILITY
1370    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>& __source)
1371    {
1372        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1373                       "merging container with incompatible allocator");
1374        return __table_.__node_handle_merge_multi(__source.__table_);
1375    }
1376    template <class _H2, class _P2>
1377    _LIBCPP_INLINE_VISIBILITY
1378    void merge(unordered_multiset<key_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_multi(__source.__table_);
1383    }
1384    template <class _H2, class _P2>
1385    _LIBCPP_INLINE_VISIBILITY
1386    void merge(unordered_set<key_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_multi(__source.__table_);
1391    }
1392    template <class _H2, class _P2>
1393    _LIBCPP_INLINE_VISIBILITY
1394    void merge(unordered_set<key_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_multi(__source.__table_);
1399    }
1400#endif
1401
1402    _LIBCPP_INLINE_VISIBILITY
1403    iterator erase(const_iterator __p) {return __table_.erase(__p);}
1404    _LIBCPP_INLINE_VISIBILITY
1405    size_type erase(const key_type& __k) {return __table_.__erase_multi(__k);}
1406    _LIBCPP_INLINE_VISIBILITY
1407    iterator erase(const_iterator __first, const_iterator __last)
1408        {return __table_.erase(__first, __last);}
1409    _LIBCPP_INLINE_VISIBILITY
1410    void clear() _NOEXCEPT {__table_.clear();}
1411
1412    _LIBCPP_INLINE_VISIBILITY
1413    void swap(unordered_multiset& __u)
1414        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
1415        {__table_.swap(__u.__table_);}
1416
1417    _LIBCPP_INLINE_VISIBILITY
1418    hasher hash_function() const {return __table_.hash_function();}
1419    _LIBCPP_INLINE_VISIBILITY
1420    key_equal key_eq() const {return __table_.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_multi(__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_multi(__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_multi(__k);}
1455    _LIBCPP_INLINE_VISIBILITY
1456    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
1457        {return __table_.__equal_range_multi(__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_multi(__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_multi(__k);}
1467#endif // _LIBCPP_STD_VER > 17
1468
1469    _LIBCPP_INLINE_VISIBILITY
1470    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
1471    _LIBCPP_INLINE_VISIBILITY
1472    size_type max_bucket_count() const _NOEXCEPT {return __table_.max_bucket_count();}
1473
1474    _LIBCPP_INLINE_VISIBILITY
1475    size_type bucket_size(size_type __n) const {return __table_.bucket_size(__n);}
1476    _LIBCPP_INLINE_VISIBILITY
1477    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
1478
1479    _LIBCPP_INLINE_VISIBILITY
1480    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
1481    _LIBCPP_INLINE_VISIBILITY
1482    local_iterator       end(size_type __n)          {return __table_.end(__n);}
1483    _LIBCPP_INLINE_VISIBILITY
1484    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
1485    _LIBCPP_INLINE_VISIBILITY
1486    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
1487    _LIBCPP_INLINE_VISIBILITY
1488    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
1489    _LIBCPP_INLINE_VISIBILITY
1490    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
1491
1492    _LIBCPP_INLINE_VISIBILITY
1493    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
1494    _LIBCPP_INLINE_VISIBILITY
1495    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
1496    _LIBCPP_INLINE_VISIBILITY
1497    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
1498    _LIBCPP_INLINE_VISIBILITY
1499    void rehash(size_type __n) {__table_.__rehash_multi(__n);}
1500    _LIBCPP_INLINE_VISIBILITY
1501    void reserve(size_type __n) {__table_.__reserve_multi(__n);}
1502
1503#ifdef _LIBCPP_ENABLE_DEBUG_MODE
1504
1505    bool __dereferenceable(const const_iterator* __i) const
1506        {return __table_.__dereferenceable(__i);}
1507    bool __decrementable(const const_iterator* __i) const
1508        {return __table_.__decrementable(__i);}
1509    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
1510        {return __table_.__addable(__i, __n);}
1511    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
1512        {return __table_.__addable(__i, __n);}
1513
1514#endif // _LIBCPP_ENABLE_DEBUG_MODE
1515
1516};
1517
1518#if _LIBCPP_STD_VER >= 17
1519template<class _InputIterator,
1520         class _Hash = hash<__iter_value_type<_InputIterator>>,
1521         class _Pred = equal_to<__iter_value_type<_InputIterator>>,
1522         class _Allocator = allocator<__iter_value_type<_InputIterator>>,
1523         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1524         class = enable_if_t<!__is_allocator<_Hash>::value>,
1525         class = enable_if_t<!is_integral<_Hash>::value>,
1526         class = enable_if_t<!__is_allocator<_Pred>::value>,
1527         class = enable_if_t<__is_allocator<_Allocator>::value>>
1528unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
1529              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1530  -> unordered_multiset<__iter_value_type<_InputIterator>, _Hash, _Pred, _Allocator>;
1531
1532template<class _Tp, class _Hash = hash<_Tp>,
1533         class _Pred = equal_to<_Tp>, class _Allocator = allocator<_Tp>,
1534         class = enable_if_t<!__is_allocator<_Hash>::value>,
1535         class = enable_if_t<!is_integral<_Hash>::value>,
1536         class = enable_if_t<!__is_allocator<_Pred>::value>,
1537         class = enable_if_t<__is_allocator<_Allocator>::value>>
1538unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type = 0,
1539              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1540  -> unordered_multiset<_Tp, _Hash, _Pred, _Allocator>;
1541
1542template<class _InputIterator, class _Allocator,
1543         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1544         class = enable_if_t<__is_allocator<_Allocator>::value>>
1545unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
1546  -> unordered_multiset<__iter_value_type<_InputIterator>,
1547                   hash<__iter_value_type<_InputIterator>>,
1548                   equal_to<__iter_value_type<_InputIterator>>,
1549                   _Allocator>;
1550
1551template<class _InputIterator, class _Hash, class _Allocator,
1552         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1553         class = enable_if_t<!__is_allocator<_Hash>::value>,
1554         class = enable_if_t<!is_integral<_Hash>::value>,
1555         class = enable_if_t<__is_allocator<_Allocator>::value>>
1556unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type,
1557              _Hash, _Allocator)
1558  -> unordered_multiset<__iter_value_type<_InputIterator>, _Hash,
1559                   equal_to<__iter_value_type<_InputIterator>>,
1560                   _Allocator>;
1561
1562template<class _Tp, class _Allocator,
1563         class = enable_if_t<__is_allocator<_Allocator>::value>>
1564unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Allocator)
1565  -> unordered_multiset<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
1566
1567template<class _Tp, class _Hash, class _Allocator,
1568         class = enable_if_t<!__is_allocator<_Hash>::value>,
1569         class = enable_if_t<!is_integral<_Hash>::value>,
1570         class = enable_if_t<__is_allocator<_Allocator>::value>>
1571unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
1572  -> unordered_multiset<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
1573#endif
1574
1575template <class _Value, class _Hash, class _Pred, class _Alloc>
1576unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1577        size_type __n, const hasher& __hf, const key_equal& __eql)
1578    : __table_(__hf, __eql)
1579{
1580    _VSTD::__debug_db_insert_c(this);
1581    __table_.__rehash_multi(__n);
1582}
1583
1584template <class _Value, class _Hash, class _Pred, class _Alloc>
1585unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1586        size_type __n, const hasher& __hf, const key_equal& __eql,
1587        const allocator_type& __a)
1588    : __table_(__hf, __eql, __a)
1589{
1590    _VSTD::__debug_db_insert_c(this);
1591    __table_.__rehash_multi(__n);
1592}
1593
1594template <class _Value, class _Hash, class _Pred, class _Alloc>
1595template <class _InputIterator>
1596unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1597        _InputIterator __first, _InputIterator __last)
1598{
1599    _VSTD::__debug_db_insert_c(this);
1600    insert(__first, __last);
1601}
1602
1603template <class _Value, class _Hash, class _Pred, class _Alloc>
1604template <class _InputIterator>
1605unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1606        _InputIterator __first, _InputIterator __last, size_type __n,
1607        const hasher& __hf, const key_equal& __eql)
1608    : __table_(__hf, __eql)
1609{
1610    _VSTD::__debug_db_insert_c(this);
1611    __table_.__rehash_multi(__n);
1612    insert(__first, __last);
1613}
1614
1615template <class _Value, class _Hash, class _Pred, class _Alloc>
1616template <class _InputIterator>
1617unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1618        _InputIterator __first, _InputIterator __last, size_type __n,
1619        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
1620    : __table_(__hf, __eql, __a)
1621{
1622    _VSTD::__debug_db_insert_c(this);
1623    __table_.__rehash_multi(__n);
1624    insert(__first, __last);
1625}
1626
1627template <class _Value, class _Hash, class _Pred, class _Alloc>
1628inline
1629unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1630        const allocator_type& __a)
1631    : __table_(__a)
1632{
1633    _VSTD::__debug_db_insert_c(this);
1634}
1635
1636template <class _Value, class _Hash, class _Pred, class _Alloc>
1637unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1638        const unordered_multiset& __u)
1639    : __table_(__u.__table_)
1640{
1641    _VSTD::__debug_db_insert_c(this);
1642    __table_.__rehash_multi(__u.bucket_count());
1643    insert(__u.begin(), __u.end());
1644}
1645
1646template <class _Value, class _Hash, class _Pred, class _Alloc>
1647unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1648        const unordered_multiset& __u, const allocator_type& __a)
1649    : __table_(__u.__table_, __a)
1650{
1651    _VSTD::__debug_db_insert_c(this);
1652    __table_.__rehash_multi(__u.bucket_count());
1653    insert(__u.begin(), __u.end());
1654}
1655
1656#ifndef _LIBCPP_CXX03_LANG
1657
1658template <class _Value, class _Hash, class _Pred, class _Alloc>
1659inline
1660unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1661        unordered_multiset&& __u)
1662    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
1663    : __table_(_VSTD::move(__u.__table_))
1664{
1665    _VSTD::__debug_db_insert_c(this);
1666    std::__debug_db_swap(this, std::addressof(__u));
1667}
1668
1669template <class _Value, class _Hash, class _Pred, class _Alloc>
1670unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1671        unordered_multiset&& __u, const allocator_type& __a)
1672    : __table_(_VSTD::move(__u.__table_), __a)
1673{
1674    _VSTD::__debug_db_insert_c(this);
1675    if (__a != __u.get_allocator())
1676    {
1677        iterator __i = __u.begin();
1678        while (__u.size() != 0)
1679            __table_.__insert_multi(_VSTD::move(__u.__table_.remove(__i++)->__value_));
1680    }
1681    else
1682        std::__debug_db_swap(this, std::addressof(__u));
1683}
1684
1685template <class _Value, class _Hash, class _Pred, class _Alloc>
1686unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1687        initializer_list<value_type> __il)
1688{
1689    _VSTD::__debug_db_insert_c(this);
1690    insert(__il.begin(), __il.end());
1691}
1692
1693template <class _Value, class _Hash, class _Pred, class _Alloc>
1694unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1695        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1696        const key_equal& __eql)
1697    : __table_(__hf, __eql)
1698{
1699    _VSTD::__debug_db_insert_c(this);
1700    __table_.__rehash_multi(__n);
1701    insert(__il.begin(), __il.end());
1702}
1703
1704template <class _Value, class _Hash, class _Pred, class _Alloc>
1705unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1706        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1707        const key_equal& __eql, const allocator_type& __a)
1708    : __table_(__hf, __eql, __a)
1709{
1710    _VSTD::__debug_db_insert_c(this);
1711    __table_.__rehash_multi(__n);
1712    insert(__il.begin(), __il.end());
1713}
1714
1715template <class _Value, class _Hash, class _Pred, class _Alloc>
1716inline
1717unordered_multiset<_Value, _Hash, _Pred, _Alloc>&
1718unordered_multiset<_Value, _Hash, _Pred, _Alloc>::operator=(
1719        unordered_multiset&& __u)
1720    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
1721{
1722    __table_ = _VSTD::move(__u.__table_);
1723    return *this;
1724}
1725
1726template <class _Value, class _Hash, class _Pred, class _Alloc>
1727inline
1728unordered_multiset<_Value, _Hash, _Pred, _Alloc>&
1729unordered_multiset<_Value, _Hash, _Pred, _Alloc>::operator=(
1730        initializer_list<value_type> __il)
1731{
1732    __table_.__assign_multi(__il.begin(), __il.end());
1733    return *this;
1734}
1735
1736#endif // _LIBCPP_CXX03_LANG
1737
1738template <class _Value, class _Hash, class _Pred, class _Alloc>
1739template <class _InputIterator>
1740inline
1741void
1742unordered_multiset<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
1743                                                         _InputIterator __last)
1744{
1745    for (; __first != __last; ++__first)
1746        __table_.__insert_multi(*__first);
1747}
1748
1749template <class _Value, class _Hash, class _Pred, class _Alloc>
1750inline _LIBCPP_INLINE_VISIBILITY
1751void
1752swap(unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
1753     unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
1754    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1755{
1756    __x.swap(__y);
1757}
1758
1759#if _LIBCPP_STD_VER > 17
1760template <class _Value, class _Hash, class _Pred, class _Alloc,
1761          class _Predicate>
1762inline _LIBCPP_INLINE_VISIBILITY
1763    typename unordered_multiset<_Value, _Hash, _Pred, _Alloc>::size_type
1764    erase_if(unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __c,
1765             _Predicate __pred) {
1766  return _VSTD::__libcpp_erase_if_container(__c, __pred);
1767}
1768#endif
1769
1770template <class _Value, class _Hash, class _Pred, class _Alloc>
1771bool
1772operator==(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
1773           const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
1774{
1775    if (__x.size() != __y.size())
1776        return false;
1777    typedef typename unordered_multiset<_Value, _Hash, _Pred, _Alloc>::const_iterator
1778                                                                 const_iterator;
1779    typedef pair<const_iterator, const_iterator> _EqRng;
1780    for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;)
1781    {
1782        _EqRng __xeq = __x.equal_range(*__i);
1783        _EqRng __yeq = __y.equal_range(*__i);
1784        if (_VSTD::distance(__xeq.first, __xeq.second) !=
1785            _VSTD::distance(__yeq.first, __yeq.second) ||
1786                  !_VSTD::is_permutation(__xeq.first, __xeq.second, __yeq.first))
1787            return false;
1788        __i = __xeq.second;
1789    }
1790    return true;
1791}
1792
1793template <class _Value, class _Hash, class _Pred, class _Alloc>
1794inline _LIBCPP_INLINE_VISIBILITY
1795bool
1796operator!=(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
1797           const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
1798{
1799    return !(__x == __y);
1800}
1801
1802_LIBCPP_END_NAMESPACE_STD
1803
1804#endif // _LIBCPP_UNORDERED_SET
1805