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// standard-mandated includes
478
479// [iterator.range]
480#include <__iterator/access.h>
481#include <__iterator/data.h>
482#include <__iterator/empty.h>
483#include <__iterator/reverse_access.h>
484#include <__iterator/size.h>
485
486// [unord.set.syn]
487#include <compare>
488#include <initializer_list>
489
490#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
491#  pragma GCC system_header
492#endif
493
494_LIBCPP_BEGIN_NAMESPACE_STD
495
496template <class _Value, class _Hash, class _Pred, class _Alloc>
497class unordered_multiset;
498
499template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>,
500          class _Alloc = allocator<_Value> >
501class _LIBCPP_TEMPLATE_VIS unordered_set
502{
503public:
504    // types
505    typedef _Value                                                     key_type;
506    typedef key_type                                                   value_type;
507    typedef __type_identity_t<_Hash>                                   hasher;
508    typedef __type_identity_t<_Pred>                                   key_equal;
509    typedef __type_identity_t<_Alloc>                                  allocator_type;
510    typedef value_type&                                                reference;
511    typedef const value_type&                                          const_reference;
512    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
513                  "Invalid allocator::value_type");
514
515private:
516    typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
517
518    __table __table_;
519
520public:
521    typedef typename __table::pointer         pointer;
522    typedef typename __table::const_pointer   const_pointer;
523    typedef typename __table::size_type       size_type;
524    typedef typename __table::difference_type difference_type;
525
526    typedef typename __table::const_iterator       iterator;
527    typedef typename __table::const_iterator       const_iterator;
528    typedef typename __table::const_local_iterator local_iterator;
529    typedef typename __table::const_local_iterator const_local_iterator;
530
531#if _LIBCPP_STD_VER > 14
532    typedef __set_node_handle<typename __table::__node, allocator_type> node_type;
533    typedef __insert_return_type<iterator, node_type> insert_return_type;
534#endif
535
536    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
537        friend class _LIBCPP_TEMPLATE_VIS unordered_set;
538    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
539        friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
540
541    _LIBCPP_INLINE_VISIBILITY
542    unordered_set()
543        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
544    {
545        _VSTD::__debug_db_insert_c(this);
546    }
547    explicit unordered_set(size_type __n, const hasher& __hf = hasher(),
548                           const key_equal& __eql = key_equal());
549#if _LIBCPP_STD_VER > 11
550    inline _LIBCPP_INLINE_VISIBILITY
551    unordered_set(size_type __n, const allocator_type& __a)
552        : unordered_set(__n, hasher(), key_equal(), __a) {}
553    inline _LIBCPP_INLINE_VISIBILITY
554    unordered_set(size_type __n, const hasher& __hf, const allocator_type& __a)
555        : unordered_set(__n, __hf, key_equal(), __a) {}
556#endif
557    unordered_set(size_type __n, const hasher& __hf, const key_equal& __eql,
558                  const allocator_type& __a);
559    template <class _InputIterator>
560        unordered_set(_InputIterator __first, _InputIterator __last);
561    template <class _InputIterator>
562        unordered_set(_InputIterator __first, _InputIterator __last,
563                      size_type __n, const hasher& __hf = hasher(),
564                      const key_equal& __eql = key_equal());
565    template <class _InputIterator>
566        unordered_set(_InputIterator __first, _InputIterator __last,
567                      size_type __n, const hasher& __hf, const key_equal& __eql,
568                      const allocator_type& __a);
569#if _LIBCPP_STD_VER > 11
570    template <class _InputIterator>
571    inline _LIBCPP_INLINE_VISIBILITY
572        unordered_set(_InputIterator __first, _InputIterator __last,
573                    size_type __n, const allocator_type& __a)
574            : unordered_set(__first, __last, __n, hasher(), key_equal(), __a) {}
575    template <class _InputIterator>
576        unordered_set(_InputIterator __first, _InputIterator __last,
577                      size_type __n, const hasher& __hf, const allocator_type& __a)
578            : unordered_set(__first, __last, __n, __hf, key_equal(), __a) {}
579#endif
580    _LIBCPP_INLINE_VISIBILITY
581    explicit unordered_set(const allocator_type& __a);
582    unordered_set(const unordered_set& __u);
583    unordered_set(const unordered_set& __u, const allocator_type& __a);
584#ifndef _LIBCPP_CXX03_LANG
585    _LIBCPP_INLINE_VISIBILITY
586    unordered_set(unordered_set&& __u)
587        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
588    unordered_set(unordered_set&& __u, const allocator_type& __a);
589    unordered_set(initializer_list<value_type> __il);
590    unordered_set(initializer_list<value_type> __il, size_type __n,
591                  const hasher& __hf = hasher(),
592                  const key_equal& __eql = key_equal());
593    unordered_set(initializer_list<value_type> __il, size_type __n,
594                  const hasher& __hf, const key_equal& __eql,
595                  const allocator_type& __a);
596#if _LIBCPP_STD_VER > 11
597    inline _LIBCPP_INLINE_VISIBILITY
598    unordered_set(initializer_list<value_type> __il, size_type __n,
599                                                      const allocator_type& __a)
600        : unordered_set(__il, __n, hasher(), key_equal(), __a) {}
601    inline _LIBCPP_INLINE_VISIBILITY
602    unordered_set(initializer_list<value_type> __il, size_type __n,
603                                  const hasher& __hf, const allocator_type& __a)
604        : unordered_set(__il, __n, __hf, key_equal(), __a) {}
605#endif
606#endif // _LIBCPP_CXX03_LANG
607    _LIBCPP_INLINE_VISIBILITY
608    ~unordered_set() {
609        static_assert(sizeof(__diagnose_unordered_container_requirements<_Value, _Hash, _Pred>(0)), "");
610    }
611
612    _LIBCPP_INLINE_VISIBILITY
613    unordered_set& operator=(const unordered_set& __u)
614    {
615        __table_ = __u.__table_;
616        return *this;
617    }
618#ifndef _LIBCPP_CXX03_LANG
619    _LIBCPP_INLINE_VISIBILITY
620    unordered_set& operator=(unordered_set&& __u)
621        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
622    _LIBCPP_INLINE_VISIBILITY
623    unordered_set& operator=(initializer_list<value_type> __il);
624#endif // _LIBCPP_CXX03_LANG
625
626    _LIBCPP_INLINE_VISIBILITY
627    allocator_type get_allocator() const _NOEXCEPT
628        {return allocator_type(__table_.__node_alloc());}
629
630    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
631    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
632    _LIBCPP_INLINE_VISIBILITY
633    size_type size() const _NOEXCEPT  {return __table_.size();}
634    _LIBCPP_INLINE_VISIBILITY
635    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
636
637    _LIBCPP_INLINE_VISIBILITY
638    iterator       begin() _NOEXCEPT        {return __table_.begin();}
639    _LIBCPP_INLINE_VISIBILITY
640    iterator       end() _NOEXCEPT          {return __table_.end();}
641    _LIBCPP_INLINE_VISIBILITY
642    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
643    _LIBCPP_INLINE_VISIBILITY
644    const_iterator end()    const _NOEXCEPT {return __table_.end();}
645    _LIBCPP_INLINE_VISIBILITY
646    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
647    _LIBCPP_INLINE_VISIBILITY
648    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
649
650#ifndef _LIBCPP_CXX03_LANG
651    template <class... _Args>
652        _LIBCPP_INLINE_VISIBILITY
653        pair<iterator, bool> emplace(_Args&&... __args)
654            {return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...);}
655    template <class... _Args>
656    _LIBCPP_INLINE_VISIBILITY
657    iterator emplace_hint(const_iterator __p, _Args&&... __args) {
658        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__p)) == this,
659            "unordered_set::emplace_hint(const_iterator, args...) called with an iterator not"
660            " referring to this unordered_set");
661        (void)__p;
662        return __table_.__emplace_unique(std::forward<_Args>(__args)...).first;
663    }
664
665    _LIBCPP_INLINE_VISIBILITY
666    pair<iterator, bool> insert(value_type&& __x)
667        {return __table_.__insert_unique(_VSTD::move(__x));}
668    _LIBCPP_INLINE_VISIBILITY
669    iterator insert(const_iterator __p, value_type&& __x) {
670        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__p)) == this,
671            "unordered_set::insert(const_iterator, value_type&&) called with an iterator not"
672            " referring to this unordered_set");
673        (void)__p;
674        return insert(std::move(__x)).first;
675    }
676
677    _LIBCPP_INLINE_VISIBILITY
678    void insert(initializer_list<value_type> __il)
679        {insert(__il.begin(), __il.end());}
680#endif // _LIBCPP_CXX03_LANG
681    _LIBCPP_INLINE_VISIBILITY
682    pair<iterator, bool> insert(const value_type& __x)
683        {return __table_.__insert_unique(__x);}
684
685    _LIBCPP_INLINE_VISIBILITY
686    iterator insert(const_iterator __p, const value_type& __x) {
687        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__p)) == this,
688            "unordered_set::insert(const_iterator, const value_type&) called with an iterator not"
689            " referring to this unordered_set");
690        (void)__p;
691        return insert(__x).first;
692    }
693    template <class _InputIterator>
694        _LIBCPP_INLINE_VISIBILITY
695        void insert(_InputIterator __first, _InputIterator __last);
696
697    _LIBCPP_INLINE_VISIBILITY
698    iterator erase(const_iterator __p) {return __table_.erase(__p);}
699    _LIBCPP_INLINE_VISIBILITY
700    size_type erase(const key_type& __k) {return __table_.__erase_unique(__k);}
701    _LIBCPP_INLINE_VISIBILITY
702    iterator erase(const_iterator __first, const_iterator __last)
703        {return __table_.erase(__first, __last);}
704    _LIBCPP_INLINE_VISIBILITY
705    void clear() _NOEXCEPT {__table_.clear();}
706
707#if _LIBCPP_STD_VER > 14
708    _LIBCPP_INLINE_VISIBILITY
709    insert_return_type insert(node_type&& __nh)
710    {
711        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
712            "node_type with incompatible allocator passed to unordered_set::insert()");
713        return __table_.template __node_handle_insert_unique<
714            node_type, insert_return_type>(_VSTD::move(__nh));
715    }
716    _LIBCPP_INLINE_VISIBILITY
717    iterator insert(const_iterator __h, node_type&& __nh)
718    {
719        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
720            "node_type with incompatible allocator passed to unordered_set::insert()");
721        return __table_.template __node_handle_insert_unique<node_type>(
722            __h, _VSTD::move(__nh));
723    }
724    _LIBCPP_INLINE_VISIBILITY
725    node_type extract(key_type const& __key)
726    {
727        return __table_.template __node_handle_extract<node_type>(__key);
728    }
729    _LIBCPP_INLINE_VISIBILITY
730    node_type extract(const_iterator __it)
731    {
732        return __table_.template __node_handle_extract<node_type>(__it);
733    }
734
735    template<class _H2, class _P2>
736    _LIBCPP_INLINE_VISIBILITY
737    void merge(unordered_set<key_type, _H2, _P2, allocator_type>& __source)
738    {
739        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
740                       "merging container with incompatible allocator");
741        __table_.__node_handle_merge_unique(__source.__table_);
742    }
743    template<class _H2, class _P2>
744    _LIBCPP_INLINE_VISIBILITY
745    void merge(unordered_set<key_type, _H2, _P2, allocator_type>&& __source)
746    {
747        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
748                       "merging container with incompatible allocator");
749        __table_.__node_handle_merge_unique(__source.__table_);
750    }
751    template<class _H2, class _P2>
752    _LIBCPP_INLINE_VISIBILITY
753    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>& __source)
754    {
755        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
756                       "merging container with incompatible allocator");
757        __table_.__node_handle_merge_unique(__source.__table_);
758    }
759    template<class _H2, class _P2>
760    _LIBCPP_INLINE_VISIBILITY
761    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>&& __source)
762    {
763        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
764                       "merging container with incompatible allocator");
765        __table_.__node_handle_merge_unique(__source.__table_);
766    }
767#endif
768
769    _LIBCPP_INLINE_VISIBILITY
770    void swap(unordered_set& __u)
771        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
772        {__table_.swap(__u.__table_);}
773
774    _LIBCPP_INLINE_VISIBILITY
775    hasher hash_function() const {return __table_.hash_function();}
776    _LIBCPP_INLINE_VISIBILITY
777    key_equal key_eq() const {return __table_.key_eq();}
778
779    _LIBCPP_INLINE_VISIBILITY
780    iterator       find(const key_type& __k)       {return __table_.find(__k);}
781    _LIBCPP_INLINE_VISIBILITY
782    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
783#if _LIBCPP_STD_VER > 17
784    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
785    _LIBCPP_INLINE_VISIBILITY
786    iterator       find(const _K2& __k)            {return __table_.find(__k);}
787    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
788    _LIBCPP_INLINE_VISIBILITY
789    const_iterator find(const _K2& __k) const      {return __table_.find(__k);}
790#endif // _LIBCPP_STD_VER > 17
791
792    _LIBCPP_INLINE_VISIBILITY
793    size_type count(const key_type& __k) const {return __table_.__count_unique(__k);}
794#if _LIBCPP_STD_VER > 17
795    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
796    _LIBCPP_INLINE_VISIBILITY
797    size_type count(const _K2& __k) const      {return __table_.__count_unique(__k);}
798#endif // _LIBCPP_STD_VER > 17
799
800#if _LIBCPP_STD_VER > 17
801    _LIBCPP_INLINE_VISIBILITY
802    bool contains(const key_type& __k) const {return find(__k) != end();}
803
804    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
805    _LIBCPP_INLINE_VISIBILITY
806    bool contains(const _K2& __k) const      {return find(__k) != end();}
807#endif // _LIBCPP_STD_VER > 17
808
809    _LIBCPP_INLINE_VISIBILITY
810    pair<iterator, iterator>             equal_range(const key_type& __k)
811        {return __table_.__equal_range_unique(__k);}
812    _LIBCPP_INLINE_VISIBILITY
813    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
814        {return __table_.__equal_range_unique(__k);}
815#if _LIBCPP_STD_VER > 17
816    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
817    _LIBCPP_INLINE_VISIBILITY
818    pair<iterator, iterator>             equal_range(const _K2& __k)
819        {return __table_.__equal_range_unique(__k);}
820    template <class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
821    _LIBCPP_INLINE_VISIBILITY
822    pair<const_iterator, const_iterator> equal_range(const _K2& __k) const
823        {return __table_.__equal_range_unique(__k);}
824#endif // _LIBCPP_STD_VER > 17
825
826    _LIBCPP_INLINE_VISIBILITY
827    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
828    _LIBCPP_INLINE_VISIBILITY
829    size_type max_bucket_count() const _NOEXCEPT {return __table_.max_bucket_count();}
830
831    _LIBCPP_INLINE_VISIBILITY
832    size_type bucket_size(size_type __n) const {return __table_.bucket_size(__n);}
833    _LIBCPP_INLINE_VISIBILITY
834    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
835
836    _LIBCPP_INLINE_VISIBILITY
837    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
838    _LIBCPP_INLINE_VISIBILITY
839    local_iterator       end(size_type __n)          {return __table_.end(__n);}
840    _LIBCPP_INLINE_VISIBILITY
841    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
842    _LIBCPP_INLINE_VISIBILITY
843    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
844    _LIBCPP_INLINE_VISIBILITY
845    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
846    _LIBCPP_INLINE_VISIBILITY
847    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
848
849    _LIBCPP_INLINE_VISIBILITY
850    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
851    _LIBCPP_INLINE_VISIBILITY
852    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
853    _LIBCPP_INLINE_VISIBILITY
854    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
855    _LIBCPP_INLINE_VISIBILITY
856    void rehash(size_type __n) {__table_.rehash(__n);}
857    _LIBCPP_INLINE_VISIBILITY
858    void reserve(size_type __n) {__table_.reserve(__n);}
859
860#ifdef _LIBCPP_ENABLE_DEBUG_MODE
861
862    bool __dereferenceable(const const_iterator* __i) const
863        {return __table_.__dereferenceable(__i);}
864    bool __decrementable(const const_iterator* __i) const
865        {return __table_.__decrementable(__i);}
866    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
867        {return __table_.__addable(__i, __n);}
868    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
869        {return __table_.__addable(__i, __n);}
870
871#endif // _LIBCPP_ENABLE_DEBUG_MODE
872
873};
874
875#if _LIBCPP_STD_VER >= 17
876template<class _InputIterator,
877         class _Hash = hash<__iter_value_type<_InputIterator>>,
878         class _Pred = equal_to<__iter_value_type<_InputIterator>>,
879         class _Allocator = allocator<__iter_value_type<_InputIterator>>,
880         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
881         class = enable_if_t<!__is_allocator<_Hash>::value>,
882         class = enable_if_t<!is_integral<_Hash>::value>,
883         class = enable_if_t<!__is_allocator<_Pred>::value>,
884         class = enable_if_t<__is_allocator<_Allocator>::value>>
885unordered_set(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
886              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
887  -> unordered_set<__iter_value_type<_InputIterator>, _Hash, _Pred, _Allocator>;
888
889template<class _Tp, class _Hash = hash<_Tp>,
890         class _Pred = equal_to<_Tp>,
891         class _Allocator = allocator<_Tp>,
892         class = enable_if_t<!__is_allocator<_Hash>::value>,
893         class = enable_if_t<!is_integral<_Hash>::value>,
894         class = enable_if_t<!__is_allocator<_Pred>::value>,
895         class = enable_if_t<__is_allocator<_Allocator>::value>>
896unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type = 0,
897              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
898  -> unordered_set<_Tp, _Hash, _Pred, _Allocator>;
899
900template<class _InputIterator, class _Allocator,
901         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
902         class = enable_if_t<__is_allocator<_Allocator>::value>>
903unordered_set(_InputIterator, _InputIterator,
904              typename allocator_traits<_Allocator>::size_type, _Allocator)
905  -> unordered_set<__iter_value_type<_InputIterator>,
906                   hash<__iter_value_type<_InputIterator>>,
907                   equal_to<__iter_value_type<_InputIterator>>,
908                   _Allocator>;
909
910template<class _InputIterator, class _Hash, class _Allocator,
911         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
912         class = enable_if_t<!__is_allocator<_Hash>::value>,
913         class = enable_if_t<!is_integral<_Hash>::value>,
914         class = enable_if_t<__is_allocator<_Allocator>::value>>
915unordered_set(_InputIterator, _InputIterator,
916              typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
917  -> unordered_set<__iter_value_type<_InputIterator>, _Hash,
918                   equal_to<__iter_value_type<_InputIterator>>,
919                   _Allocator>;
920
921template<class _Tp, class _Allocator,
922         class = enable_if_t<__is_allocator<_Allocator>::value>>
923unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Allocator)
924  -> unordered_set<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
925
926template<class _Tp, class _Hash, class _Allocator,
927         class = enable_if_t<!__is_allocator<_Hash>::value>,
928         class = enable_if_t<!is_integral<_Hash>::value>,
929         class = enable_if_t<__is_allocator<_Allocator>::value>>
930unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
931  -> unordered_set<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
932#endif
933
934template <class _Value, class _Hash, class _Pred, class _Alloc>
935unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(size_type __n,
936        const hasher& __hf, const key_equal& __eql)
937    : __table_(__hf, __eql)
938{
939    _VSTD::__debug_db_insert_c(this);
940    __table_.rehash(__n);
941}
942
943template <class _Value, class _Hash, class _Pred, class _Alloc>
944unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(size_type __n,
945        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
946    : __table_(__hf, __eql, __a)
947{
948    _VSTD::__debug_db_insert_c(this);
949    __table_.rehash(__n);
950}
951
952template <class _Value, class _Hash, class _Pred, class _Alloc>
953template <class _InputIterator>
954unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
955        _InputIterator __first, _InputIterator __last)
956{
957    _VSTD::__debug_db_insert_c(this);
958    insert(__first, __last);
959}
960
961template <class _Value, class _Hash, class _Pred, class _Alloc>
962template <class _InputIterator>
963unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
964        _InputIterator __first, _InputIterator __last, size_type __n,
965        const hasher& __hf, const key_equal& __eql)
966    : __table_(__hf, __eql)
967{
968    _VSTD::__debug_db_insert_c(this);
969    __table_.rehash(__n);
970    insert(__first, __last);
971}
972
973template <class _Value, class _Hash, class _Pred, class _Alloc>
974template <class _InputIterator>
975unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
976        _InputIterator __first, _InputIterator __last, size_type __n,
977        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
978    : __table_(__hf, __eql, __a)
979{
980    _VSTD::__debug_db_insert_c(this);
981    __table_.rehash(__n);
982    insert(__first, __last);
983}
984
985template <class _Value, class _Hash, class _Pred, class _Alloc>
986inline
987unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
988        const allocator_type& __a)
989    : __table_(__a)
990{
991    _VSTD::__debug_db_insert_c(this);
992}
993
994template <class _Value, class _Hash, class _Pred, class _Alloc>
995unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
996        const unordered_set& __u)
997    : __table_(__u.__table_)
998{
999    _VSTD::__debug_db_insert_c(this);
1000    __table_.rehash(__u.bucket_count());
1001    insert(__u.begin(), __u.end());
1002}
1003
1004template <class _Value, class _Hash, class _Pred, class _Alloc>
1005unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1006        const unordered_set& __u, const allocator_type& __a)
1007    : __table_(__u.__table_, __a)
1008{
1009    _VSTD::__debug_db_insert_c(this);
1010    __table_.rehash(__u.bucket_count());
1011    insert(__u.begin(), __u.end());
1012}
1013
1014#ifndef _LIBCPP_CXX03_LANG
1015
1016template <class _Value, class _Hash, class _Pred, class _Alloc>
1017inline
1018unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1019        unordered_set&& __u)
1020    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
1021    : __table_(_VSTD::move(__u.__table_))
1022{
1023    _VSTD::__debug_db_insert_c(this);
1024    std::__debug_db_swap(this, std::addressof(__u));
1025}
1026
1027template <class _Value, class _Hash, class _Pred, class _Alloc>
1028unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1029        unordered_set&& __u, const allocator_type& __a)
1030    : __table_(_VSTD::move(__u.__table_), __a)
1031{
1032    _VSTD::__debug_db_insert_c(this);
1033    if (__a != __u.get_allocator())
1034    {
1035        iterator __i = __u.begin();
1036        while (__u.size() != 0)
1037            __table_.__insert_unique(_VSTD::move(__u.__table_.remove(__i++)->__value_));
1038    }
1039    else
1040        std::__debug_db_swap(this, std::addressof(__u));
1041}
1042
1043template <class _Value, class _Hash, class _Pred, class _Alloc>
1044unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1045        initializer_list<value_type> __il)
1046{
1047    _VSTD::__debug_db_insert_c(this);
1048    insert(__il.begin(), __il.end());
1049}
1050
1051template <class _Value, class _Hash, class _Pred, class _Alloc>
1052unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1053        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1054        const key_equal& __eql)
1055    : __table_(__hf, __eql)
1056{
1057    _VSTD::__debug_db_insert_c(this);
1058    __table_.rehash(__n);
1059    insert(__il.begin(), __il.end());
1060}
1061
1062template <class _Value, class _Hash, class _Pred, class _Alloc>
1063unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
1064        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1065        const key_equal& __eql, const allocator_type& __a)
1066    : __table_(__hf, __eql, __a)
1067{
1068    _VSTD::__debug_db_insert_c(this);
1069    __table_.rehash(__n);
1070    insert(__il.begin(), __il.end());
1071}
1072
1073template <class _Value, class _Hash, class _Pred, class _Alloc>
1074inline
1075unordered_set<_Value, _Hash, _Pred, _Alloc>&
1076unordered_set<_Value, _Hash, _Pred, _Alloc>::operator=(unordered_set&& __u)
1077    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
1078{
1079    __table_ = _VSTD::move(__u.__table_);
1080    return *this;
1081}
1082
1083template <class _Value, class _Hash, class _Pred, class _Alloc>
1084inline
1085unordered_set<_Value, _Hash, _Pred, _Alloc>&
1086unordered_set<_Value, _Hash, _Pred, _Alloc>::operator=(
1087        initializer_list<value_type> __il)
1088{
1089    __table_.__assign_unique(__il.begin(), __il.end());
1090    return *this;
1091}
1092
1093#endif // _LIBCPP_CXX03_LANG
1094
1095template <class _Value, class _Hash, class _Pred, class _Alloc>
1096template <class _InputIterator>
1097inline
1098void
1099unordered_set<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
1100                                                    _InputIterator __last)
1101{
1102    for (; __first != __last; ++__first)
1103        __table_.__insert_unique(*__first);
1104}
1105
1106template <class _Value, class _Hash, class _Pred, class _Alloc>
1107inline _LIBCPP_INLINE_VISIBILITY
1108void
1109swap(unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
1110     unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
1111    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1112{
1113    __x.swap(__y);
1114}
1115
1116#if _LIBCPP_STD_VER > 17
1117template <class _Value, class _Hash, class _Pred, class _Alloc,
1118          class _Predicate>
1119inline _LIBCPP_INLINE_VISIBILITY
1120    typename unordered_set<_Value, _Hash, _Pred, _Alloc>::size_type
1121    erase_if(unordered_set<_Value, _Hash, _Pred, _Alloc>& __c,
1122             _Predicate __pred) {
1123  return _VSTD::__libcpp_erase_if_container(__c, __pred);
1124}
1125#endif
1126
1127template <class _Value, class _Hash, class _Pred, class _Alloc>
1128bool
1129operator==(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
1130           const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
1131{
1132    if (__x.size() != __y.size())
1133        return false;
1134    typedef typename unordered_set<_Value, _Hash, _Pred, _Alloc>::const_iterator
1135                                                                 const_iterator;
1136    for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end();
1137            __i != __ex; ++__i)
1138    {
1139        const_iterator __j = __y.find(*__i);
1140        if (__j == __ey || !(*__i == *__j))
1141            return false;
1142    }
1143    return true;
1144}
1145
1146template <class _Value, class _Hash, class _Pred, class _Alloc>
1147inline _LIBCPP_INLINE_VISIBILITY
1148bool
1149operator!=(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
1150           const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
1151{
1152    return !(__x == __y);
1153}
1154
1155template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>,
1156          class _Alloc = allocator<_Value> >
1157class _LIBCPP_TEMPLATE_VIS unordered_multiset
1158{
1159public:
1160    // types
1161    typedef _Value                                                     key_type;
1162    typedef key_type                                                   value_type;
1163    typedef __type_identity_t<_Hash>                                   hasher;
1164    typedef __type_identity_t<_Pred>                                   key_equal;
1165    typedef __type_identity_t<_Alloc>                                  allocator_type;
1166    typedef value_type&                                                reference;
1167    typedef const value_type&                                          const_reference;
1168    static_assert((is_same<value_type, typename allocator_type::value_type>::value),
1169                  "Invalid allocator::value_type");
1170
1171private:
1172    typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
1173
1174    __table __table_;
1175
1176public:
1177    typedef typename __table::pointer         pointer;
1178    typedef typename __table::const_pointer   const_pointer;
1179    typedef typename __table::size_type       size_type;
1180    typedef typename __table::difference_type difference_type;
1181
1182    typedef typename __table::const_iterator       iterator;
1183    typedef typename __table::const_iterator       const_iterator;
1184    typedef typename __table::const_local_iterator local_iterator;
1185    typedef typename __table::const_local_iterator const_local_iterator;
1186
1187#if _LIBCPP_STD_VER > 14
1188    typedef __set_node_handle<typename __table::__node, allocator_type> node_type;
1189#endif
1190
1191    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
1192        friend class _LIBCPP_TEMPLATE_VIS unordered_set;
1193    template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
1194        friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
1195
1196    _LIBCPP_INLINE_VISIBILITY
1197    unordered_multiset()
1198        _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
1199    {
1200        _VSTD::__debug_db_insert_c(this);
1201    }
1202    explicit unordered_multiset(size_type __n, const hasher& __hf = hasher(),
1203                                const key_equal& __eql = key_equal());
1204    unordered_multiset(size_type __n, const hasher& __hf,
1205                       const key_equal& __eql, const allocator_type& __a);
1206#if _LIBCPP_STD_VER > 11
1207    inline _LIBCPP_INLINE_VISIBILITY
1208    unordered_multiset(size_type __n, const allocator_type& __a)
1209        : unordered_multiset(__n, hasher(), key_equal(), __a) {}
1210    inline _LIBCPP_INLINE_VISIBILITY
1211    unordered_multiset(size_type __n, const hasher& __hf, const allocator_type& __a)
1212        : unordered_multiset(__n, __hf, key_equal(), __a) {}
1213#endif
1214    template <class _InputIterator>
1215        unordered_multiset(_InputIterator __first, _InputIterator __last);
1216    template <class _InputIterator>
1217        unordered_multiset(_InputIterator __first, _InputIterator __last,
1218                      size_type __n, const hasher& __hf = hasher(),
1219                      const key_equal& __eql = key_equal());
1220    template <class _InputIterator>
1221        unordered_multiset(_InputIterator __first, _InputIterator __last,
1222                      size_type __n , const hasher& __hf,
1223                      const key_equal& __eql, const allocator_type& __a);
1224#if _LIBCPP_STD_VER > 11
1225    template <class _InputIterator>
1226    inline _LIBCPP_INLINE_VISIBILITY
1227    unordered_multiset(_InputIterator __first, _InputIterator __last,
1228                       size_type __n, const allocator_type& __a)
1229        : unordered_multiset(__first, __last, __n, hasher(), key_equal(), __a) {}
1230    template <class _InputIterator>
1231    inline _LIBCPP_INLINE_VISIBILITY
1232    unordered_multiset(_InputIterator __first, _InputIterator __last,
1233                       size_type __n, const hasher& __hf, const allocator_type& __a)
1234        : unordered_multiset(__first, __last, __n, __hf, key_equal(), __a) {}
1235#endif
1236    _LIBCPP_INLINE_VISIBILITY
1237    explicit unordered_multiset(const allocator_type& __a);
1238    unordered_multiset(const unordered_multiset& __u);
1239    unordered_multiset(const unordered_multiset& __u, const allocator_type& __a);
1240#ifndef _LIBCPP_CXX03_LANG
1241    _LIBCPP_INLINE_VISIBILITY
1242    unordered_multiset(unordered_multiset&& __u)
1243        _NOEXCEPT_(is_nothrow_move_constructible<__table>::value);
1244    unordered_multiset(unordered_multiset&& __u, const allocator_type& __a);
1245    unordered_multiset(initializer_list<value_type> __il);
1246    unordered_multiset(initializer_list<value_type> __il, size_type __n,
1247                       const hasher& __hf = hasher(),
1248                       const key_equal& __eql = key_equal());
1249    unordered_multiset(initializer_list<value_type> __il, size_type __n,
1250                       const hasher& __hf, const key_equal& __eql,
1251                       const allocator_type& __a);
1252#if _LIBCPP_STD_VER > 11
1253    inline _LIBCPP_INLINE_VISIBILITY
1254    unordered_multiset(initializer_list<value_type> __il, size_type __n, const allocator_type& __a)
1255      : unordered_multiset(__il, __n, hasher(), key_equal(), __a) {}
1256    inline _LIBCPP_INLINE_VISIBILITY
1257    unordered_multiset(initializer_list<value_type> __il, size_type __n, const hasher& __hf, const allocator_type& __a)
1258      : unordered_multiset(__il, __n, __hf, key_equal(), __a) {}
1259#endif
1260#endif // _LIBCPP_CXX03_LANG
1261    _LIBCPP_INLINE_VISIBILITY
1262    ~unordered_multiset() {
1263        static_assert(sizeof(__diagnose_unordered_container_requirements<_Value, _Hash, _Pred>(0)), "");
1264    }
1265
1266    _LIBCPP_INLINE_VISIBILITY
1267    unordered_multiset& operator=(const unordered_multiset& __u)
1268    {
1269        __table_ = __u.__table_;
1270        return *this;
1271    }
1272#ifndef _LIBCPP_CXX03_LANG
1273    _LIBCPP_INLINE_VISIBILITY
1274    unordered_multiset& operator=(unordered_multiset&& __u)
1275        _NOEXCEPT_(is_nothrow_move_assignable<__table>::value);
1276    unordered_multiset& operator=(initializer_list<value_type> __il);
1277#endif // _LIBCPP_CXX03_LANG
1278
1279    _LIBCPP_INLINE_VISIBILITY
1280    allocator_type get_allocator() const _NOEXCEPT
1281        {return allocator_type(__table_.__node_alloc());}
1282
1283    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1284    bool      empty() const _NOEXCEPT {return __table_.size() == 0;}
1285    _LIBCPP_INLINE_VISIBILITY
1286    size_type size() const _NOEXCEPT  {return __table_.size();}
1287    _LIBCPP_INLINE_VISIBILITY
1288    size_type max_size() const _NOEXCEPT {return __table_.max_size();}
1289
1290    _LIBCPP_INLINE_VISIBILITY
1291    iterator       begin() _NOEXCEPT        {return __table_.begin();}
1292    _LIBCPP_INLINE_VISIBILITY
1293    iterator       end() _NOEXCEPT          {return __table_.end();}
1294    _LIBCPP_INLINE_VISIBILITY
1295    const_iterator begin()  const _NOEXCEPT {return __table_.begin();}
1296    _LIBCPP_INLINE_VISIBILITY
1297    const_iterator end()    const _NOEXCEPT {return __table_.end();}
1298    _LIBCPP_INLINE_VISIBILITY
1299    const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
1300    _LIBCPP_INLINE_VISIBILITY
1301    const_iterator cend()   const _NOEXCEPT {return __table_.end();}
1302
1303#ifndef _LIBCPP_CXX03_LANG
1304    template <class... _Args>
1305        _LIBCPP_INLINE_VISIBILITY
1306        iterator emplace(_Args&&... __args)
1307            {return __table_.__emplace_multi(_VSTD::forward<_Args>(__args)...);}
1308    template <class... _Args>
1309        _LIBCPP_INLINE_VISIBILITY
1310        iterator emplace_hint(const_iterator __p, _Args&&... __args)
1311            {return __table_.__emplace_hint_multi(__p, _VSTD::forward<_Args>(__args)...);}
1312
1313    _LIBCPP_INLINE_VISIBILITY
1314    iterator insert(value_type&& __x) {return __table_.__insert_multi(_VSTD::move(__x));}
1315    _LIBCPP_INLINE_VISIBILITY
1316    iterator insert(const_iterator __p, value_type&& __x)
1317        {return __table_.__insert_multi(__p, _VSTD::move(__x));}
1318    _LIBCPP_INLINE_VISIBILITY
1319    void insert(initializer_list<value_type> __il)
1320        {insert(__il.begin(), __il.end());}
1321#endif // _LIBCPP_CXX03_LANG
1322
1323    _LIBCPP_INLINE_VISIBILITY
1324    iterator insert(const value_type& __x) {return __table_.__insert_multi(__x);}
1325
1326    _LIBCPP_INLINE_VISIBILITY
1327    iterator insert(const_iterator __p, const value_type& __x)
1328        {return __table_.__insert_multi(__p, __x);}
1329
1330    template <class _InputIterator>
1331        _LIBCPP_INLINE_VISIBILITY
1332        void insert(_InputIterator __first, _InputIterator __last);
1333
1334#if _LIBCPP_STD_VER > 14
1335    _LIBCPP_INLINE_VISIBILITY
1336    iterator insert(node_type&& __nh)
1337    {
1338        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1339            "node_type with incompatible allocator passed to unordered_multiset::insert()");
1340        return __table_.template __node_handle_insert_multi<node_type>(
1341            _VSTD::move(__nh));
1342    }
1343    _LIBCPP_INLINE_VISIBILITY
1344    iterator insert(const_iterator __hint, node_type&& __nh)
1345    {
1346        _LIBCPP_ASSERT(__nh.empty() || __nh.get_allocator() == get_allocator(),
1347            "node_type with incompatible allocator passed to unordered_multiset::insert()");
1348        return __table_.template __node_handle_insert_multi<node_type>(
1349            __hint, _VSTD::move(__nh));
1350    }
1351    _LIBCPP_INLINE_VISIBILITY
1352    node_type extract(const_iterator __position)
1353    {
1354        return __table_.template __node_handle_extract<node_type>(
1355            __position);
1356    }
1357    _LIBCPP_INLINE_VISIBILITY
1358    node_type extract(key_type const& __key)
1359    {
1360        return __table_.template __node_handle_extract<node_type>(__key);
1361    }
1362
1363    template <class _H2, class _P2>
1364    _LIBCPP_INLINE_VISIBILITY
1365    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>& __source)
1366    {
1367        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1368                       "merging container with incompatible allocator");
1369        return __table_.__node_handle_merge_multi(__source.__table_);
1370    }
1371    template <class _H2, class _P2>
1372    _LIBCPP_INLINE_VISIBILITY
1373    void merge(unordered_multiset<key_type, _H2, _P2, allocator_type>&& __source)
1374    {
1375        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1376                       "merging container with incompatible allocator");
1377        return __table_.__node_handle_merge_multi(__source.__table_);
1378    }
1379    template <class _H2, class _P2>
1380    _LIBCPP_INLINE_VISIBILITY
1381    void merge(unordered_set<key_type, _H2, _P2, allocator_type>& __source)
1382    {
1383        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1384                       "merging container with incompatible allocator");
1385        return __table_.__node_handle_merge_multi(__source.__table_);
1386    }
1387    template <class _H2, class _P2>
1388    _LIBCPP_INLINE_VISIBILITY
1389    void merge(unordered_set<key_type, _H2, _P2, allocator_type>&& __source)
1390    {
1391        _LIBCPP_ASSERT(__source.get_allocator() == get_allocator(),
1392                       "merging container with incompatible allocator");
1393        return __table_.__node_handle_merge_multi(__source.__table_);
1394    }
1395#endif
1396
1397    _LIBCPP_INLINE_VISIBILITY
1398    iterator erase(const_iterator __p) {return __table_.erase(__p);}
1399    _LIBCPP_INLINE_VISIBILITY
1400    size_type erase(const key_type& __k) {return __table_.__erase_multi(__k);}
1401    _LIBCPP_INLINE_VISIBILITY
1402    iterator erase(const_iterator __first, const_iterator __last)
1403        {return __table_.erase(__first, __last);}
1404    _LIBCPP_INLINE_VISIBILITY
1405    void clear() _NOEXCEPT {__table_.clear();}
1406
1407    _LIBCPP_INLINE_VISIBILITY
1408    void swap(unordered_multiset& __u)
1409        _NOEXCEPT_(__is_nothrow_swappable<__table>::value)
1410        {__table_.swap(__u.__table_);}
1411
1412    _LIBCPP_INLINE_VISIBILITY
1413    hasher hash_function() const {return __table_.hash_function();}
1414    _LIBCPP_INLINE_VISIBILITY
1415    key_equal key_eq() const {return __table_.key_eq();}
1416
1417    _LIBCPP_INLINE_VISIBILITY
1418    iterator       find(const key_type& __k)       {return __table_.find(__k);}
1419    _LIBCPP_INLINE_VISIBILITY
1420    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
1421#if _LIBCPP_STD_VER > 17
1422    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1423    _LIBCPP_INLINE_VISIBILITY
1424    iterator       find(const _K2& __k)            {return __table_.find(__k);}
1425    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1426    _LIBCPP_INLINE_VISIBILITY
1427    const_iterator find(const _K2& __k) const      {return __table_.find(__k);}
1428#endif // _LIBCPP_STD_VER > 17
1429
1430    _LIBCPP_INLINE_VISIBILITY
1431    size_type count(const key_type& __k) const {return __table_.__count_multi(__k);}
1432#if _LIBCPP_STD_VER > 17
1433    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1434    _LIBCPP_INLINE_VISIBILITY
1435    size_type count(const _K2& __k) const      {return __table_.__count_multi(__k);}
1436#endif // _LIBCPP_STD_VER > 17
1437
1438#if _LIBCPP_STD_VER > 17
1439    _LIBCPP_INLINE_VISIBILITY
1440    bool contains(const key_type& __k) const {return find(__k) != end();}
1441
1442    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1443    _LIBCPP_INLINE_VISIBILITY
1444    bool contains(const _K2& __k) const      {return find(__k) != end();}
1445#endif // _LIBCPP_STD_VER > 17
1446
1447    _LIBCPP_INLINE_VISIBILITY
1448    pair<iterator, iterator>             equal_range(const key_type& __k)
1449        {return __table_.__equal_range_multi(__k);}
1450    _LIBCPP_INLINE_VISIBILITY
1451    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
1452        {return __table_.__equal_range_multi(__k);}
1453#if _LIBCPP_STD_VER > 17
1454    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1455    _LIBCPP_INLINE_VISIBILITY
1456    pair<iterator, iterator>             equal_range(const _K2& __k)
1457        {return __table_.__equal_range_multi(__k);}
1458    template<class _K2, enable_if_t<__is_transparent<hasher, _K2>::value && __is_transparent<key_equal, _K2>::value>* = nullptr>
1459    _LIBCPP_INLINE_VISIBILITY
1460    pair<const_iterator, const_iterator> equal_range(const _K2& __k) const
1461        {return __table_.__equal_range_multi(__k);}
1462#endif // _LIBCPP_STD_VER > 17
1463
1464    _LIBCPP_INLINE_VISIBILITY
1465    size_type bucket_count() const _NOEXCEPT {return __table_.bucket_count();}
1466    _LIBCPP_INLINE_VISIBILITY
1467    size_type max_bucket_count() const _NOEXCEPT {return __table_.max_bucket_count();}
1468
1469    _LIBCPP_INLINE_VISIBILITY
1470    size_type bucket_size(size_type __n) const {return __table_.bucket_size(__n);}
1471    _LIBCPP_INLINE_VISIBILITY
1472    size_type bucket(const key_type& __k) const {return __table_.bucket(__k);}
1473
1474    _LIBCPP_INLINE_VISIBILITY
1475    local_iterator       begin(size_type __n)        {return __table_.begin(__n);}
1476    _LIBCPP_INLINE_VISIBILITY
1477    local_iterator       end(size_type __n)          {return __table_.end(__n);}
1478    _LIBCPP_INLINE_VISIBILITY
1479    const_local_iterator begin(size_type __n) const  {return __table_.cbegin(__n);}
1480    _LIBCPP_INLINE_VISIBILITY
1481    const_local_iterator end(size_type __n) const    {return __table_.cend(__n);}
1482    _LIBCPP_INLINE_VISIBILITY
1483    const_local_iterator cbegin(size_type __n) const {return __table_.cbegin(__n);}
1484    _LIBCPP_INLINE_VISIBILITY
1485    const_local_iterator cend(size_type __n) const   {return __table_.cend(__n);}
1486
1487    _LIBCPP_INLINE_VISIBILITY
1488    float load_factor() const _NOEXCEPT {return __table_.load_factor();}
1489    _LIBCPP_INLINE_VISIBILITY
1490    float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
1491    _LIBCPP_INLINE_VISIBILITY
1492    void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
1493    _LIBCPP_INLINE_VISIBILITY
1494    void rehash(size_type __n) {__table_.rehash(__n);}
1495    _LIBCPP_INLINE_VISIBILITY
1496    void reserve(size_type __n) {__table_.reserve(__n);}
1497
1498#ifdef _LIBCPP_ENABLE_DEBUG_MODE
1499
1500    bool __dereferenceable(const const_iterator* __i) const
1501        {return __table_.__dereferenceable(__i);}
1502    bool __decrementable(const const_iterator* __i) const
1503        {return __table_.__decrementable(__i);}
1504    bool __addable(const const_iterator* __i, ptrdiff_t __n) const
1505        {return __table_.__addable(__i, __n);}
1506    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
1507        {return __table_.__addable(__i, __n);}
1508
1509#endif // _LIBCPP_ENABLE_DEBUG_MODE
1510
1511};
1512
1513#if _LIBCPP_STD_VER >= 17
1514template<class _InputIterator,
1515         class _Hash = hash<__iter_value_type<_InputIterator>>,
1516         class _Pred = equal_to<__iter_value_type<_InputIterator>>,
1517         class _Allocator = allocator<__iter_value_type<_InputIterator>>,
1518         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1519         class = enable_if_t<!__is_allocator<_Hash>::value>,
1520         class = enable_if_t<!is_integral<_Hash>::value>,
1521         class = enable_if_t<!__is_allocator<_Pred>::value>,
1522         class = enable_if_t<__is_allocator<_Allocator>::value>>
1523unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type = 0,
1524              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1525  -> unordered_multiset<__iter_value_type<_InputIterator>, _Hash, _Pred, _Allocator>;
1526
1527template<class _Tp, class _Hash = hash<_Tp>,
1528         class _Pred = equal_to<_Tp>, class _Allocator = allocator<_Tp>,
1529         class = enable_if_t<!__is_allocator<_Hash>::value>,
1530         class = enable_if_t<!is_integral<_Hash>::value>,
1531         class = enable_if_t<!__is_allocator<_Pred>::value>,
1532         class = enable_if_t<__is_allocator<_Allocator>::value>>
1533unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type = 0,
1534              _Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
1535  -> unordered_multiset<_Tp, _Hash, _Pred, _Allocator>;
1536
1537template<class _InputIterator, class _Allocator,
1538         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1539         class = enable_if_t<__is_allocator<_Allocator>::value>>
1540unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type, _Allocator)
1541  -> unordered_multiset<__iter_value_type<_InputIterator>,
1542                   hash<__iter_value_type<_InputIterator>>,
1543                   equal_to<__iter_value_type<_InputIterator>>,
1544                   _Allocator>;
1545
1546template<class _InputIterator, class _Hash, class _Allocator,
1547         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
1548         class = enable_if_t<!__is_allocator<_Hash>::value>,
1549         class = enable_if_t<!is_integral<_Hash>::value>,
1550         class = enable_if_t<__is_allocator<_Allocator>::value>>
1551unordered_multiset(_InputIterator, _InputIterator, typename allocator_traits<_Allocator>::size_type,
1552              _Hash, _Allocator)
1553  -> unordered_multiset<__iter_value_type<_InputIterator>, _Hash,
1554                   equal_to<__iter_value_type<_InputIterator>>,
1555                   _Allocator>;
1556
1557template<class _Tp, class _Allocator,
1558         class = enable_if_t<__is_allocator<_Allocator>::value>>
1559unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Allocator)
1560  -> unordered_multiset<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
1561
1562template<class _Tp, class _Hash, class _Allocator,
1563         class = enable_if_t<!__is_allocator<_Hash>::value>,
1564         class = enable_if_t<!is_integral<_Hash>::value>,
1565         class = enable_if_t<__is_allocator<_Allocator>::value>>
1566unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
1567  -> unordered_multiset<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
1568#endif
1569
1570template <class _Value, class _Hash, class _Pred, class _Alloc>
1571unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1572        size_type __n, const hasher& __hf, const key_equal& __eql)
1573    : __table_(__hf, __eql)
1574{
1575    _VSTD::__debug_db_insert_c(this);
1576    __table_.rehash(__n);
1577}
1578
1579template <class _Value, class _Hash, class _Pred, class _Alloc>
1580unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1581        size_type __n, const hasher& __hf, const key_equal& __eql,
1582        const allocator_type& __a)
1583    : __table_(__hf, __eql, __a)
1584{
1585    _VSTD::__debug_db_insert_c(this);
1586    __table_.rehash(__n);
1587}
1588
1589template <class _Value, class _Hash, class _Pred, class _Alloc>
1590template <class _InputIterator>
1591unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1592        _InputIterator __first, _InputIterator __last)
1593{
1594    _VSTD::__debug_db_insert_c(this);
1595    insert(__first, __last);
1596}
1597
1598template <class _Value, class _Hash, class _Pred, class _Alloc>
1599template <class _InputIterator>
1600unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1601        _InputIterator __first, _InputIterator __last, size_type __n,
1602        const hasher& __hf, const key_equal& __eql)
1603    : __table_(__hf, __eql)
1604{
1605    _VSTD::__debug_db_insert_c(this);
1606    __table_.rehash(__n);
1607    insert(__first, __last);
1608}
1609
1610template <class _Value, class _Hash, class _Pred, class _Alloc>
1611template <class _InputIterator>
1612unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1613        _InputIterator __first, _InputIterator __last, size_type __n,
1614        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
1615    : __table_(__hf, __eql, __a)
1616{
1617    _VSTD::__debug_db_insert_c(this);
1618    __table_.rehash(__n);
1619    insert(__first, __last);
1620}
1621
1622template <class _Value, class _Hash, class _Pred, class _Alloc>
1623inline
1624unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1625        const allocator_type& __a)
1626    : __table_(__a)
1627{
1628    _VSTD::__debug_db_insert_c(this);
1629}
1630
1631template <class _Value, class _Hash, class _Pred, class _Alloc>
1632unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1633        const unordered_multiset& __u)
1634    : __table_(__u.__table_)
1635{
1636    _VSTD::__debug_db_insert_c(this);
1637    __table_.rehash(__u.bucket_count());
1638    insert(__u.begin(), __u.end());
1639}
1640
1641template <class _Value, class _Hash, class _Pred, class _Alloc>
1642unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1643        const unordered_multiset& __u, const allocator_type& __a)
1644    : __table_(__u.__table_, __a)
1645{
1646    _VSTD::__debug_db_insert_c(this);
1647    __table_.rehash(__u.bucket_count());
1648    insert(__u.begin(), __u.end());
1649}
1650
1651#ifndef _LIBCPP_CXX03_LANG
1652
1653template <class _Value, class _Hash, class _Pred, class _Alloc>
1654inline
1655unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1656        unordered_multiset&& __u)
1657    _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
1658    : __table_(_VSTD::move(__u.__table_))
1659{
1660    _VSTD::__debug_db_insert_c(this);
1661    std::__debug_db_swap(this, std::addressof(__u));
1662}
1663
1664template <class _Value, class _Hash, class _Pred, class _Alloc>
1665unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1666        unordered_multiset&& __u, const allocator_type& __a)
1667    : __table_(_VSTD::move(__u.__table_), __a)
1668{
1669    _VSTD::__debug_db_insert_c(this);
1670    if (__a != __u.get_allocator())
1671    {
1672        iterator __i = __u.begin();
1673        while (__u.size() != 0)
1674            __table_.__insert_multi(_VSTD::move(__u.__table_.remove(__i++)->__value_));
1675    }
1676    else
1677        std::__debug_db_swap(this, std::addressof(__u));
1678}
1679
1680template <class _Value, class _Hash, class _Pred, class _Alloc>
1681unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1682        initializer_list<value_type> __il)
1683{
1684    _VSTD::__debug_db_insert_c(this);
1685    insert(__il.begin(), __il.end());
1686}
1687
1688template <class _Value, class _Hash, class _Pred, class _Alloc>
1689unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1690        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1691        const key_equal& __eql)
1692    : __table_(__hf, __eql)
1693{
1694    _VSTD::__debug_db_insert_c(this);
1695    __table_.rehash(__n);
1696    insert(__il.begin(), __il.end());
1697}
1698
1699template <class _Value, class _Hash, class _Pred, class _Alloc>
1700unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
1701        initializer_list<value_type> __il, size_type __n, const hasher& __hf,
1702        const key_equal& __eql, const allocator_type& __a)
1703    : __table_(__hf, __eql, __a)
1704{
1705    _VSTD::__debug_db_insert_c(this);
1706    __table_.rehash(__n);
1707    insert(__il.begin(), __il.end());
1708}
1709
1710template <class _Value, class _Hash, class _Pred, class _Alloc>
1711inline
1712unordered_multiset<_Value, _Hash, _Pred, _Alloc>&
1713unordered_multiset<_Value, _Hash, _Pred, _Alloc>::operator=(
1714        unordered_multiset&& __u)
1715    _NOEXCEPT_(is_nothrow_move_assignable<__table>::value)
1716{
1717    __table_ = _VSTD::move(__u.__table_);
1718    return *this;
1719}
1720
1721template <class _Value, class _Hash, class _Pred, class _Alloc>
1722inline
1723unordered_multiset<_Value, _Hash, _Pred, _Alloc>&
1724unordered_multiset<_Value, _Hash, _Pred, _Alloc>::operator=(
1725        initializer_list<value_type> __il)
1726{
1727    __table_.__assign_multi(__il.begin(), __il.end());
1728    return *this;
1729}
1730
1731#endif // _LIBCPP_CXX03_LANG
1732
1733template <class _Value, class _Hash, class _Pred, class _Alloc>
1734template <class _InputIterator>
1735inline
1736void
1737unordered_multiset<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
1738                                                         _InputIterator __last)
1739{
1740    for (; __first != __last; ++__first)
1741        __table_.__insert_multi(*__first);
1742}
1743
1744template <class _Value, class _Hash, class _Pred, class _Alloc>
1745inline _LIBCPP_INLINE_VISIBILITY
1746void
1747swap(unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
1748     unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
1749    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
1750{
1751    __x.swap(__y);
1752}
1753
1754#if _LIBCPP_STD_VER > 17
1755template <class _Value, class _Hash, class _Pred, class _Alloc,
1756          class _Predicate>
1757inline _LIBCPP_INLINE_VISIBILITY
1758    typename unordered_multiset<_Value, _Hash, _Pred, _Alloc>::size_type
1759    erase_if(unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __c,
1760             _Predicate __pred) {
1761  return _VSTD::__libcpp_erase_if_container(__c, __pred);
1762}
1763#endif
1764
1765template <class _Value, class _Hash, class _Pred, class _Alloc>
1766bool
1767operator==(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
1768           const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
1769{
1770    if (__x.size() != __y.size())
1771        return false;
1772    typedef typename unordered_multiset<_Value, _Hash, _Pred, _Alloc>::const_iterator
1773                                                                 const_iterator;
1774    typedef pair<const_iterator, const_iterator> _EqRng;
1775    for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;)
1776    {
1777        _EqRng __xeq = __x.equal_range(*__i);
1778        _EqRng __yeq = __y.equal_range(*__i);
1779        if (_VSTD::distance(__xeq.first, __xeq.second) !=
1780            _VSTD::distance(__yeq.first, __yeq.second) ||
1781                  !_VSTD::is_permutation(__xeq.first, __xeq.second, __yeq.first))
1782            return false;
1783        __i = __xeq.second;
1784    }
1785    return true;
1786}
1787
1788template <class _Value, class _Hash, class _Pred, class _Alloc>
1789inline _LIBCPP_INLINE_VISIBILITY
1790bool
1791operator!=(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
1792           const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
1793{
1794    return !(__x == __y);
1795}
1796
1797_LIBCPP_END_NAMESPACE_STD
1798
1799#endif // _LIBCPP_UNORDERED_SET
1800