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_VECTOR
11#define _LIBCPP_VECTOR
12
13/*
14    vector synopsis
15
16namespace std
17{
18
19template <class T, class Allocator = allocator<T> >
20class vector
21{
22public:
23    typedef T                                        value_type;
24    typedef Allocator                                allocator_type;
25    typedef typename allocator_type::reference       reference;
26    typedef typename allocator_type::const_reference const_reference;
27    typedef implementation-defined                   iterator;
28    typedef implementation-defined                   const_iterator;
29    typedef typename allocator_type::size_type       size_type;
30    typedef typename allocator_type::difference_type difference_type;
31    typedef typename allocator_type::pointer         pointer;
32    typedef typename allocator_type::const_pointer   const_pointer;
33    typedef std::reverse_iterator<iterator>          reverse_iterator;
34    typedef std::reverse_iterator<const_iterator>    const_reverse_iterator;
35
36    vector()
37        noexcept(is_nothrow_default_constructible<allocator_type>::value);
38    explicit vector(const allocator_type&);
39    explicit vector(size_type n);
40    explicit vector(size_type n, const allocator_type&); // C++14
41    vector(size_type n, const value_type& value, const allocator_type& = allocator_type());
42    template <class InputIterator>
43        vector(InputIterator first, InputIterator last, const allocator_type& = allocator_type());
44    vector(const vector& x);
45    vector(vector&& x)
46        noexcept(is_nothrow_move_constructible<allocator_type>::value);
47    vector(initializer_list<value_type> il);
48    vector(initializer_list<value_type> il, const allocator_type& a);
49    ~vector();
50    vector& operator=(const vector& x);
51    vector& operator=(vector&& x)
52        noexcept(
53             allocator_type::propagate_on_container_move_assignment::value ||
54             allocator_type::is_always_equal::value); // C++17
55    vector& operator=(initializer_list<value_type> il);
56    template <class InputIterator>
57        void assign(InputIterator first, InputIterator last);
58    void assign(size_type n, const value_type& u);
59    void assign(initializer_list<value_type> il);
60
61    allocator_type get_allocator() const noexcept;
62
63    iterator               begin() noexcept;
64    const_iterator         begin()   const noexcept;
65    iterator               end() noexcept;
66    const_iterator         end()     const noexcept;
67
68    reverse_iterator       rbegin() noexcept;
69    const_reverse_iterator rbegin()  const noexcept;
70    reverse_iterator       rend() noexcept;
71    const_reverse_iterator rend()    const noexcept;
72
73    const_iterator         cbegin()  const noexcept;
74    const_iterator         cend()    const noexcept;
75    const_reverse_iterator crbegin() const noexcept;
76    const_reverse_iterator crend()   const noexcept;
77
78    size_type size() const noexcept;
79    size_type max_size() const noexcept;
80    size_type capacity() const noexcept;
81    bool empty() const noexcept;
82    void reserve(size_type n);
83    void shrink_to_fit() noexcept;
84
85    reference       operator[](size_type n);
86    const_reference operator[](size_type n) const;
87    reference       at(size_type n);
88    const_reference at(size_type n) const;
89
90    reference       front();
91    const_reference front() const;
92    reference       back();
93    const_reference back() const;
94
95    value_type*       data() noexcept;
96    const value_type* data() const noexcept;
97
98    void push_back(const value_type& x);
99    void push_back(value_type&& x);
100    template <class... Args>
101        reference emplace_back(Args&&... args); // reference in C++17
102    void pop_back();
103
104    template <class... Args> iterator emplace(const_iterator position, Args&&... args);
105    iterator insert(const_iterator position, const value_type& x);
106    iterator insert(const_iterator position, value_type&& x);
107    iterator insert(const_iterator position, size_type n, const value_type& x);
108    template <class InputIterator>
109        iterator insert(const_iterator position, InputIterator first, InputIterator last);
110    iterator insert(const_iterator position, initializer_list<value_type> il);
111
112    iterator erase(const_iterator position);
113    iterator erase(const_iterator first, const_iterator last);
114
115    void clear() noexcept;
116
117    void resize(size_type sz);
118    void resize(size_type sz, const value_type& c);
119
120    void swap(vector&)
121        noexcept(allocator_traits<allocator_type>::propagate_on_container_swap::value ||
122                 allocator_traits<allocator_type>::is_always_equal::value);  // C++17
123
124    bool __invariants() const;
125};
126
127template <class Allocator = allocator<T> >
128class vector<bool, Allocator>
129{
130public:
131    typedef bool                                     value_type;
132    typedef Allocator                                allocator_type;
133    typedef implementation-defined                   iterator;
134    typedef implementation-defined                   const_iterator;
135    typedef typename allocator_type::size_type       size_type;
136    typedef typename allocator_type::difference_type difference_type;
137    typedef iterator                                 pointer;
138    typedef const_iterator                           const_pointer;
139    typedef std::reverse_iterator<iterator>          reverse_iterator;
140    typedef std::reverse_iterator<const_iterator>    const_reverse_iterator;
141
142    class reference
143    {
144    public:
145        reference(const reference&) noexcept;
146        operator bool() const noexcept;
147        reference& operator=(bool x) noexcept;
148        reference& operator=(const reference& x) noexcept;
149        iterator operator&() const noexcept;
150        void flip() noexcept;
151    };
152
153    class const_reference
154    {
155    public:
156        const_reference(const reference&) noexcept;
157        operator bool() const noexcept;
158        const_iterator operator&() const noexcept;
159    };
160
161    vector()
162        noexcept(is_nothrow_default_constructible<allocator_type>::value);
163    explicit vector(const allocator_type&);
164    explicit vector(size_type n, const allocator_type& a = allocator_type()); // C++14
165    vector(size_type n, const value_type& value, const allocator_type& = allocator_type());
166    template <class InputIterator>
167        vector(InputIterator first, InputIterator last, const allocator_type& = allocator_type());
168    vector(const vector& x);
169    vector(vector&& x)
170        noexcept(is_nothrow_move_constructible<allocator_type>::value);
171    vector(initializer_list<value_type> il);
172    vector(initializer_list<value_type> il, const allocator_type& a);
173    ~vector();
174    vector& operator=(const vector& x);
175    vector& operator=(vector&& x)
176        noexcept(
177             allocator_type::propagate_on_container_move_assignment::value ||
178             allocator_type::is_always_equal::value); // C++17
179    vector& operator=(initializer_list<value_type> il);
180    template <class InputIterator>
181        void assign(InputIterator first, InputIterator last);
182    void assign(size_type n, const value_type& u);
183    void assign(initializer_list<value_type> il);
184
185    allocator_type get_allocator() const noexcept;
186
187    iterator               begin() noexcept;
188    const_iterator         begin()   const noexcept;
189    iterator               end() noexcept;
190    const_iterator         end()     const noexcept;
191
192    reverse_iterator       rbegin() noexcept;
193    const_reverse_iterator rbegin()  const noexcept;
194    reverse_iterator       rend() noexcept;
195    const_reverse_iterator rend()    const noexcept;
196
197    const_iterator         cbegin()  const noexcept;
198    const_iterator         cend()    const noexcept;
199    const_reverse_iterator crbegin() const noexcept;
200    const_reverse_iterator crend()   const noexcept;
201
202    size_type size() const noexcept;
203    size_type max_size() const noexcept;
204    size_type capacity() const noexcept;
205    bool empty() const noexcept;
206    void reserve(size_type n);
207    void shrink_to_fit() noexcept;
208
209    reference       operator[](size_type n);
210    const_reference operator[](size_type n) const;
211    reference       at(size_type n);
212    const_reference at(size_type n) const;
213
214    reference       front();
215    const_reference front() const;
216    reference       back();
217    const_reference back() const;
218
219    void push_back(const value_type& x);
220    template <class... Args> reference emplace_back(Args&&... args);  // C++14; reference in C++17
221    void pop_back();
222
223    template <class... Args> iterator emplace(const_iterator position, Args&&... args);  // C++14
224    iterator insert(const_iterator position, const value_type& x);
225    iterator insert(const_iterator position, size_type n, const value_type& x);
226    template <class InputIterator>
227        iterator insert(const_iterator position, InputIterator first, InputIterator last);
228    iterator insert(const_iterator position, initializer_list<value_type> il);
229
230    iterator erase(const_iterator position);
231    iterator erase(const_iterator first, const_iterator last);
232
233    void clear() noexcept;
234
235    void resize(size_type sz);
236    void resize(size_type sz, value_type x);
237
238    void swap(vector&)
239        noexcept(allocator_traits<allocator_type>::propagate_on_container_swap::value ||
240                 allocator_traits<allocator_type>::is_always_equal::value);  // C++17
241    void flip() noexcept;
242
243    bool __invariants() const;
244};
245
246template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
247   vector(InputIterator, InputIterator, Allocator = Allocator())
248   -> vector<typename iterator_traits<InputIterator>::value_type, Allocator>; // C++17
249
250template <class Allocator> struct hash<std::vector<bool, Allocator>>;
251
252template <class T, class Allocator> bool operator==(const vector<T,Allocator>& x, const vector<T,Allocator>& y);
253template <class T, class Allocator> bool operator< (const vector<T,Allocator>& x, const vector<T,Allocator>& y);
254template <class T, class Allocator> bool operator!=(const vector<T,Allocator>& x, const vector<T,Allocator>& y);
255template <class T, class Allocator> bool operator> (const vector<T,Allocator>& x, const vector<T,Allocator>& y);
256template <class T, class Allocator> bool operator>=(const vector<T,Allocator>& x, const vector<T,Allocator>& y);
257template <class T, class Allocator> bool operator<=(const vector<T,Allocator>& x, const vector<T,Allocator>& y);
258
259template <class T, class Allocator>
260void swap(vector<T,Allocator>& x, vector<T,Allocator>& y)
261    noexcept(noexcept(x.swap(y)));
262
263template <class T, class Allocator, class U>
264typename vector<T, Allocator>::size_type
265erase(vector<T, Allocator>& c, const U& value);       // C++20
266template <class T, class Allocator, class Predicate>
267typename vector<T, Allocator>::size_type
268erase_if(vector<T, Allocator>& c, Predicate pred);    // C++20
269
270
271template<class T>
272 inline constexpr bool is-vector-bool-reference = see below;        // exposition only, since C++23
273
274template<class T, class charT> requires is-vector-bool-reference<T> // Since C++23
275 struct formatter<T, charT>;
276
277}  // std
278
279*/
280
281#include <__algorithm/copy.h>
282#include <__algorithm/equal.h>
283#include <__algorithm/fill_n.h>
284#include <__algorithm/lexicographical_compare.h>
285#include <__algorithm/remove.h>
286#include <__algorithm/remove_if.h>
287#include <__algorithm/rotate.h>
288#include <__algorithm/unwrap_iter.h>
289#include <__assert> // all public C++ headers provide the assertion handler
290#include <__bit_reference>
291#include <__concepts/same_as.h>
292#include <__config>
293#include <__debug>
294#include <__format/enable_insertable.h>
295#include <__format/formatter.h>
296#include <__functional/hash.h>
297#include <__functional/unary_function.h>
298#include <__iterator/advance.h>
299#include <__iterator/iterator_traits.h>
300#include <__iterator/reverse_iterator.h>
301#include <__iterator/wrap_iter.h>
302#include <__memory/allocate_at_least.h>
303#include <__memory/pointer_traits.h>
304#include <__memory/swap_allocator.h>
305#include <__memory/temp_value.h>
306#include <__memory/uninitialized_algorithms.h>
307#include <__memory_resource/polymorphic_allocator.h>
308#include <__split_buffer>
309#include <__type_traits/is_allocator.h>
310#include <__type_traits/noexcept_move_assign_container.h>
311#include <__utility/exception_guard.h>
312#include <__utility/forward.h>
313#include <__utility/move.h>
314#include <__utility/swap.h>
315#include <climits>
316#include <cstdlib>
317#include <cstring>
318#include <iosfwd> // for forward declaration of vector
319#include <limits>
320#include <stdexcept>
321#include <type_traits>
322#include <version>
323
324// standard-mandated includes
325
326// [iterator.range]
327#include <__iterator/access.h>
328#include <__iterator/data.h>
329#include <__iterator/empty.h>
330#include <__iterator/reverse_access.h>
331#include <__iterator/size.h>
332
333// [vector.syn]
334#include <compare>
335#include <initializer_list>
336
337#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
338#  pragma GCC system_header
339#endif
340
341_LIBCPP_PUSH_MACROS
342#include <__undef_macros>
343
344
345_LIBCPP_BEGIN_NAMESPACE_STD
346
347template <class _Tp, class _Allocator /* = allocator<_Tp> */>
348class _LIBCPP_TEMPLATE_VIS vector
349{
350private:
351    typedef allocator<_Tp>                                  __default_allocator_type;
352public:
353    typedef vector                                          __self;
354    typedef _Tp                                             value_type;
355    typedef _Allocator                                      allocator_type;
356    typedef allocator_traits<allocator_type>                __alloc_traits;
357    typedef value_type&                                     reference;
358    typedef const value_type&                               const_reference;
359    typedef typename __alloc_traits::size_type              size_type;
360    typedef typename __alloc_traits::difference_type        difference_type;
361    typedef typename __alloc_traits::pointer                pointer;
362    typedef typename __alloc_traits::const_pointer          const_pointer;
363    // TODO: Implement iterator bounds checking without requiring the global database.
364    typedef __wrap_iter<pointer>                            iterator;
365    typedef __wrap_iter<const_pointer>                      const_iterator;
366    typedef std::reverse_iterator<iterator>               reverse_iterator;
367    typedef std::reverse_iterator<const_iterator>         const_reverse_iterator;
368
369    static_assert((is_same<typename allocator_type::value_type, value_type>::value),
370                  "Allocator::value_type must be same type as value_type");
371
372    static_assert(is_same<allocator_type, __rebind_alloc<__alloc_traits, value_type> >::value,
373                  "[allocator.requirements] states that rebinding an allocator to the same type should result in the "
374                  "original allocator");
375
376    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
377    vector() _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
378    {
379        std::__debug_db_insert_c(this);
380    }
381    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit vector(const allocator_type& __a)
382#if _LIBCPP_STD_VER <= 14
383        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
384#else
385        _NOEXCEPT
386#endif
387        : __end_cap_(nullptr, __a)
388    {
389        std::__debug_db_insert_c(this);
390    }
391    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit vector(size_type __n);
392#if _LIBCPP_STD_VER > 11
393    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit vector(size_type __n, const allocator_type& __a);
394#endif
395    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(size_type __n, const value_type& __x);
396
397    template <class = __enable_if_t<__is_allocator<_Allocator>::value> >
398    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
399    vector(size_type __n, const value_type& __x, const allocator_type& __a)
400        : __end_cap_(nullptr, __a)
401    {
402      std::__debug_db_insert_c(this);
403      if (__n > 0)
404      {
405          __vallocate(__n);
406          __construct_at_end(__n, __x);
407      }
408    }
409
410  template <class _InputIterator,
411            __enable_if_t<__is_exactly_cpp17_input_iterator<_InputIterator>::value &&
412                              is_constructible<value_type, typename iterator_traits<_InputIterator>::reference>::value,
413                          int> = 0>
414  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(_InputIterator __first, _InputIterator __last);
415  template <class _InputIterator,
416            __enable_if_t<__is_exactly_cpp17_input_iterator<_InputIterator>::value &&
417                              is_constructible<value_type, typename iterator_traits<_InputIterator>::reference>::value,
418                          int> = 0>
419  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
420  vector(_InputIterator __first, _InputIterator __last, const allocator_type& __a);
421
422  template <
423      class _ForwardIterator,
424      __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value &&
425                        is_constructible<value_type, typename iterator_traits<_ForwardIterator>::reference>::value,
426                    int> = 0>
427  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(_ForwardIterator __first, _ForwardIterator __last);
428
429  template <class _ForwardIterator,
430      __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value &&
431                        is_constructible<value_type, typename iterator_traits<_ForwardIterator>::reference>::value,
432                    int> = 0>
433  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
434  vector(_ForwardIterator __first, _ForwardIterator __last, const allocator_type& __a);
435
436private:
437  class __destroy_vector {
438    public:
439      _LIBCPP_CONSTEXPR __destroy_vector(vector& __vec) : __vec_(__vec) {}
440
441      _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void operator()() {
442          __vec_.__annotate_delete();
443          std::__debug_db_erase_c(std::addressof(__vec_));
444
445          if (__vec_.__begin_ != nullptr) {
446            __vec_.__clear();
447            __alloc_traits::deallocate(__vec_.__alloc(), __vec_.__begin_, __vec_.capacity());
448          }
449      }
450
451    private:
452      vector& __vec_;
453  };
454
455public:
456  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~vector() { __destroy_vector(*this)(); }
457
458    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(const vector& __x);
459    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(const vector& __x, const __type_identity_t<allocator_type>& __a);
460    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
461    vector& operator=(const vector& __x);
462
463#ifndef _LIBCPP_CXX03_LANG
464    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
465    vector(initializer_list<value_type> __il);
466
467    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
468    vector(initializer_list<value_type> __il, const allocator_type& __a);
469
470    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
471    vector& operator=(initializer_list<value_type> __il)
472        {assign(__il.begin(), __il.end()); return *this;}
473#endif // !_LIBCPP_CXX03_LANG
474
475    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
476    vector(vector&& __x)
477#if _LIBCPP_STD_VER > 14
478        noexcept;
479#else
480        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
481#endif
482
483    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
484    vector(vector&& __x, const __type_identity_t<allocator_type>& __a);
485    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
486    vector& operator=(vector&& __x)
487        _NOEXCEPT_((__noexcept_move_assign_container<_Allocator, __alloc_traits>::value));
488
489  template <class _InputIterator,
490            __enable_if_t<__is_exactly_cpp17_input_iterator<_InputIterator>::value &&
491                              is_constructible<value_type, typename iterator_traits<_InputIterator>::reference>::value,
492                          int> = 0>
493  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void assign(_InputIterator __first, _InputIterator __last);
494  template <
495      class _ForwardIterator,
496      __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value &&
497                        is_constructible<value_type, typename iterator_traits<_ForwardIterator>::reference>::value,
498                    int> = 0>
499  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void assign(_ForwardIterator __first, _ForwardIterator __last);
500
501    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void assign(size_type __n, const_reference __u);
502
503#ifndef _LIBCPP_CXX03_LANG
504    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
505    void assign(initializer_list<value_type> __il)
506        {assign(__il.begin(), __il.end());}
507#endif
508
509    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
510    allocator_type get_allocator() const _NOEXCEPT
511        {return this->__alloc();}
512
513    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator               begin() _NOEXCEPT;
514    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator         begin()   const _NOEXCEPT;
515    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator               end() _NOEXCEPT;
516    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_iterator         end()     const _NOEXCEPT;
517
518    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
519    reverse_iterator       rbegin() _NOEXCEPT
520        {return       reverse_iterator(end());}
521    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
522    const_reverse_iterator rbegin()  const _NOEXCEPT
523        {return const_reverse_iterator(end());}
524    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
525    reverse_iterator       rend() _NOEXCEPT
526        {return       reverse_iterator(begin());}
527    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
528    const_reverse_iterator rend()    const _NOEXCEPT
529        {return const_reverse_iterator(begin());}
530
531    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
532    const_iterator         cbegin()  const _NOEXCEPT
533        {return begin();}
534    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
535    const_iterator         cend()    const _NOEXCEPT
536        {return end();}
537    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
538    const_reverse_iterator crbegin() const _NOEXCEPT
539        {return rbegin();}
540    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
541    const_reverse_iterator crend()   const _NOEXCEPT
542        {return rend();}
543
544    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
545    size_type size() const _NOEXCEPT
546        {return static_cast<size_type>(this->__end_ - this->__begin_);}
547    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
548    size_type capacity() const _NOEXCEPT
549        {return static_cast<size_type>(__end_cap() - this->__begin_);}
550    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
551    bool empty() const _NOEXCEPT
552        {return this->__begin_ == this->__end_;}
553    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type max_size() const _NOEXCEPT;
554    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void reserve(size_type __n);
555    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void shrink_to_fit() _NOEXCEPT;
556
557    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference       operator[](size_type __n) _NOEXCEPT;
558    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference operator[](size_type __n) const _NOEXCEPT;
559    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference       at(size_type __n);
560    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference at(size_type __n) const;
561
562    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference       front() _NOEXCEPT
563    {
564        _LIBCPP_ASSERT(!empty(), "front() called on an empty vector");
565        return *this->__begin_;
566    }
567    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference front() const _NOEXCEPT
568    {
569        _LIBCPP_ASSERT(!empty(), "front() called on an empty vector");
570        return *this->__begin_;
571    }
572    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI reference       back() _NOEXCEPT
573    {
574        _LIBCPP_ASSERT(!empty(), "back() called on an empty vector");
575        return *(this->__end_ - 1);
576    }
577    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI const_reference back()  const _NOEXCEPT
578    {
579        _LIBCPP_ASSERT(!empty(), "back() called on an empty vector");
580        return *(this->__end_ - 1);
581    }
582
583    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
584    value_type*       data() _NOEXCEPT
585        {return std::__to_address(this->__begin_);}
586
587    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
588    const value_type* data() const _NOEXCEPT
589        {return std::__to_address(this->__begin_);}
590
591    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(const_reference __x);
592
593    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void push_back(value_type&& __x);
594
595    template <class... _Args>
596    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
597#if _LIBCPP_STD_VER > 14
598        reference emplace_back(_Args&&... __args);
599#else
600        void      emplace_back(_Args&&... __args);
601#endif
602
603    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
604    void pop_back();
605
606    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __position, const_reference __x);
607
608    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __position, value_type&& __x);
609    template <class... _Args>
610    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator emplace(const_iterator __position, _Args&&... __args);
611
612    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
613    iterator insert(const_iterator __position, size_type __n, const_reference __x);
614
615  template <class _InputIterator,
616            __enable_if_t<__is_exactly_cpp17_input_iterator<_InputIterator>::value &&
617                              is_constructible< value_type, typename iterator_traits<_InputIterator>::reference>::value,
618                          int> = 0>
619  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
620  insert(const_iterator __position, _InputIterator __first, _InputIterator __last);
621
622  template <
623      class _ForwardIterator,
624      __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value &&
625                        is_constructible< value_type, typename iterator_traits<_ForwardIterator>::reference>::value,
626                    int> = 0>
627  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator
628  insert(const_iterator __position, _ForwardIterator __first, _ForwardIterator __last);
629
630#ifndef _LIBCPP_CXX03_LANG
631    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
632    iterator insert(const_iterator __position, initializer_list<value_type> __il)
633        {return insert(__position, __il.begin(), __il.end());}
634#endif
635
636    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __position);
637    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last);
638
639    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
640    void clear() _NOEXCEPT
641    {
642        size_type __old_size = size();
643        __clear();
644        __annotate_shrink(__old_size);
645        std::__debug_db_invalidate_all(this);
646    }
647
648    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void resize(size_type __sz);
649    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void resize(size_type __sz, const_reference __x);
650
651    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void swap(vector&)
652#if _LIBCPP_STD_VER >= 14
653        _NOEXCEPT;
654#else
655        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
656                    __is_nothrow_swappable<allocator_type>::value);
657#endif
658
659    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool __invariants() const;
660
661#ifdef _LIBCPP_ENABLE_DEBUG_MODE
662
663    bool __dereferenceable(const const_iterator* __i) const;
664    bool __decrementable(const const_iterator* __i) const;
665    bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
666    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;
667
668#endif // _LIBCPP_ENABLE_DEBUG_MODE
669
670private:
671    pointer __begin_ = nullptr;
672    pointer __end_ = nullptr;
673    __compressed_pair<pointer, allocator_type> __end_cap_ =
674        __compressed_pair<pointer, allocator_type>(nullptr, __default_init_tag());
675
676    _LIBCPP_HIDE_FROM_ABI void __invalidate_iterators_past(pointer __new_last);
677
678    //  Allocate space for __n objects
679    //  throws length_error if __n > max_size()
680    //  throws (probably bad_alloc) if memory run out
681    //  Precondition:  __begin_ == __end_ == __end_cap() == 0
682    //  Precondition:  __n > 0
683    //  Postcondition:  capacity() >= __n
684    //  Postcondition:  size() == 0
685    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __vallocate(size_type __n) {
686        if (__n > max_size())
687            __throw_length_error();
688        auto __allocation = std::__allocate_at_least(__alloc(), __n);
689        __begin_ = __allocation.ptr;
690        __end_ = __allocation.ptr;
691        __end_cap() = __begin_ + __allocation.count;
692        __annotate_new(0);
693    }
694
695    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __vdeallocate() _NOEXCEPT;
696    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI size_type __recommend(size_type __new_size) const;
697    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n);
698    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
699    void __construct_at_end(size_type __n, const_reference __x);
700
701  template <class _ForwardIterator, __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value, int> = 0>
702  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void
703  __construct_at_end(_ForwardIterator __first, _ForwardIterator __last, size_type __n);
704
705    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __append(size_type __n);
706    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __append(size_type __n, const_reference __x);
707    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
708    iterator       __make_iter(pointer __p) _NOEXCEPT { return iterator(this, __p); }
709    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
710    const_iterator __make_iter(const_pointer __p) const _NOEXCEPT { return const_iterator(this, __p); }
711    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v);
712    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pointer __swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v, pointer __p);
713    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_range(pointer __from_s, pointer __from_e, pointer __to);
714    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign(vector& __c, true_type)
715        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
716    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign(vector& __c, false_type)
717        _NOEXCEPT_(__alloc_traits::is_always_equal::value);
718    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
719    void __destruct_at_end(pointer __new_last) _NOEXCEPT
720    {
721        if (!__libcpp_is_constant_evaluated())
722            __invalidate_iterators_past(__new_last);
723        size_type __old_size = size();
724        __base_destruct_at_end(__new_last);
725        __annotate_shrink(__old_size);
726    }
727
728    template <class _Up>
729    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
730    inline void __push_back_slow_path(_Up&& __x);
731
732    template <class... _Args>
733    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
734    inline void __emplace_back_slow_path(_Args&&... __args);
735
736    // The following functions are no-ops outside of AddressSanitizer mode.
737    // We call annotatations only for the default Allocator because other allocators
738    // may not meet the AddressSanitizer alignment constraints.
739    // See the documentation for __sanitizer_annotate_contiguous_container for more details.
740#ifndef _LIBCPP_HAS_NO_ASAN
741    _LIBCPP_CONSTEXPR_SINCE_CXX20
742    void __annotate_contiguous_container(const void *__beg, const void *__end,
743                                         const void *__old_mid,
744                                         const void *__new_mid) const
745    {
746
747      if (!__libcpp_is_constant_evaluated() && __beg && is_same<allocator_type, __default_allocator_type>::value)
748        __sanitizer_annotate_contiguous_container(__beg, __end, __old_mid, __new_mid);
749    }
750#else
751    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
752    void __annotate_contiguous_container(const void*, const void*, const void*,
753                                         const void*) const _NOEXCEPT {}
754#endif
755    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
756    void __annotate_new(size_type __current_size) const _NOEXCEPT {
757      __annotate_contiguous_container(data(), data() + capacity(),
758                                      data() + capacity(), data() + __current_size);
759    }
760
761    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
762    void __annotate_delete() const _NOEXCEPT {
763      __annotate_contiguous_container(data(), data() + capacity(),
764                                      data() + size(), data() + capacity());
765    }
766
767    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
768    void __annotate_increase(size_type __n) const _NOEXCEPT
769    {
770      __annotate_contiguous_container(data(), data() + capacity(),
771                                      data() + size(), data() + size() + __n);
772    }
773
774    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
775    void __annotate_shrink(size_type __old_size) const _NOEXCEPT
776    {
777      __annotate_contiguous_container(data(), data() + capacity(),
778                                      data() + __old_size, data() + size());
779    }
780
781  struct _ConstructTransaction {
782    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
783    explicit _ConstructTransaction(vector &__v, size_type __n)
784      : __v_(__v), __pos_(__v.__end_), __new_end_(__v.__end_ + __n) {
785#ifndef _LIBCPP_HAS_NO_ASAN
786      __v_.__annotate_increase(__n);
787#endif
788    }
789    _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~_ConstructTransaction() {
790      __v_.__end_ = __pos_;
791#ifndef _LIBCPP_HAS_NO_ASAN
792      if (__pos_ != __new_end_) {
793        __v_.__annotate_shrink(__new_end_ - __v_.__begin_);
794      }
795#endif
796    }
797
798    vector &__v_;
799    pointer __pos_;
800    const_pointer const __new_end_;
801
802  private:
803    _ConstructTransaction(_ConstructTransaction const&) = delete;
804    _ConstructTransaction& operator=(_ConstructTransaction const&) = delete;
805  };
806
807  template <class ..._Args>
808  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
809  void __construct_one_at_end(_Args&& ...__args) {
810    _ConstructTransaction __tx(*this, 1);
811    __alloc_traits::construct(this->__alloc(), std::__to_address(__tx.__pos_),
812        std::forward<_Args>(__args)...);
813    ++__tx.__pos_;
814  }
815
816  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
817  allocator_type& __alloc() _NOEXCEPT
818      {return this->__end_cap_.second();}
819  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
820  const allocator_type& __alloc() const _NOEXCEPT
821      {return this->__end_cap_.second();}
822  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
823  pointer& __end_cap() _NOEXCEPT
824      {return this->__end_cap_.first();}
825  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
826  const pointer& __end_cap() const _NOEXCEPT
827      {return this->__end_cap_.first();}
828
829  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
830  void __clear() _NOEXCEPT {__base_destruct_at_end(this->__begin_);}
831
832  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
833  void __base_destruct_at_end(pointer __new_last) _NOEXCEPT {
834    pointer __soon_to_be_end = this->__end_;
835    while (__new_last != __soon_to_be_end)
836        __alloc_traits::destroy(__alloc(), std::__to_address(--__soon_to_be_end));
837    this->__end_ = __new_last;
838  }
839
840  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
841  void __copy_assign_alloc(const vector& __c)
842      {__copy_assign_alloc(__c, integral_constant<bool,
843                    __alloc_traits::propagate_on_container_copy_assignment::value>());}
844
845  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
846  void __move_assign_alloc(vector& __c)
847      _NOEXCEPT_(
848          !__alloc_traits::propagate_on_container_move_assignment::value ||
849          is_nothrow_move_assignable<allocator_type>::value)
850      {__move_assign_alloc(__c, integral_constant<bool,
851                    __alloc_traits::propagate_on_container_move_assignment::value>());}
852
853  _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI
854  void __throw_length_error() const {
855      std::__throw_length_error("vector");
856  }
857
858  _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI
859  void __throw_out_of_range() const {
860      std::__throw_out_of_range("vector");
861  }
862
863  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
864  void __copy_assign_alloc(const vector& __c, true_type)
865  {
866    if (__alloc() != __c.__alloc())
867    {
868      __clear();
869      __alloc_traits::deallocate(__alloc(), this->__begin_, capacity());
870      this->__begin_ = this->__end_ = __end_cap() = nullptr;
871    }
872    __alloc() = __c.__alloc();
873  }
874
875  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
876  void __copy_assign_alloc(const vector&, false_type)
877  {}
878
879  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
880  void __move_assign_alloc(vector& __c, true_type)
881      _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
882  {
883    __alloc() = std::move(__c.__alloc());
884  }
885
886  _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
887  void __move_assign_alloc(vector&, false_type)
888      _NOEXCEPT
889  {}
890};
891
892#if _LIBCPP_STD_VER >= 17
893template<class _InputIterator,
894         class _Alloc = allocator<__iter_value_type<_InputIterator>>,
895         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
896         class = enable_if_t<__is_allocator<_Alloc>::value>
897         >
898vector(_InputIterator, _InputIterator)
899  -> vector<__iter_value_type<_InputIterator>, _Alloc>;
900
901template<class _InputIterator,
902         class _Alloc,
903         class = enable_if_t<__is_cpp17_input_iterator<_InputIterator>::value>,
904         class = enable_if_t<__is_allocator<_Alloc>::value>
905         >
906vector(_InputIterator, _InputIterator, _Alloc)
907  -> vector<__iter_value_type<_InputIterator>, _Alloc>;
908#endif
909
910template <class _Tp, class _Allocator>
911_LIBCPP_CONSTEXPR_SINCE_CXX20
912void
913vector<_Tp, _Allocator>::__swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v)
914{
915    __annotate_delete();
916    using _RevIter = std::reverse_iterator<pointer>;
917    __v.__begin_   = std::__uninitialized_allocator_move_if_noexcept(
918                       __alloc(), _RevIter(__end_), _RevIter(__begin_), _RevIter(__v.__begin_))
919                       .base();
920    std::swap(this->__begin_, __v.__begin_);
921    std::swap(this->__end_, __v.__end_);
922    std::swap(this->__end_cap(), __v.__end_cap());
923    __v.__first_ = __v.__begin_;
924    __annotate_new(size());
925    std::__debug_db_invalidate_all(this);
926}
927
928template <class _Tp, class _Allocator>
929_LIBCPP_CONSTEXPR_SINCE_CXX20
930typename vector<_Tp, _Allocator>::pointer
931vector<_Tp, _Allocator>::__swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v, pointer __p)
932{
933    __annotate_delete();
934    pointer __r = __v.__begin_;
935    using _RevIter = std::reverse_iterator<pointer>;
936    __v.__begin_   = std::__uninitialized_allocator_move_if_noexcept(
937                       __alloc(), _RevIter(__p), _RevIter(__begin_), _RevIter(__v.__begin_))
938                       .base();
939    __v.__end_ = std::__uninitialized_allocator_move_if_noexcept(__alloc(), __p, __end_, __v.__end_);
940    std::swap(this->__begin_, __v.__begin_);
941    std::swap(this->__end_, __v.__end_);
942    std::swap(this->__end_cap(), __v.__end_cap());
943    __v.__first_ = __v.__begin_;
944    __annotate_new(size());
945    std::__debug_db_invalidate_all(this);
946    return __r;
947}
948
949template <class _Tp, class _Allocator>
950_LIBCPP_CONSTEXPR_SINCE_CXX20
951void
952vector<_Tp, _Allocator>::__vdeallocate() _NOEXCEPT
953{
954    if (this->__begin_ != nullptr)
955    {
956        clear();
957        __alloc_traits::deallocate(this->__alloc(), this->__begin_, capacity());
958        this->__begin_ = this->__end_ = this->__end_cap() = nullptr;
959    }
960}
961
962template <class _Tp, class _Allocator>
963_LIBCPP_CONSTEXPR_SINCE_CXX20
964typename vector<_Tp, _Allocator>::size_type
965vector<_Tp, _Allocator>::max_size() const _NOEXCEPT
966{
967    return std::min<size_type>(__alloc_traits::max_size(this->__alloc()),
968                                 numeric_limits<difference_type>::max());
969}
970
971//  Precondition:  __new_size > capacity()
972template <class _Tp, class _Allocator>
973_LIBCPP_CONSTEXPR_SINCE_CXX20
974inline _LIBCPP_HIDE_FROM_ABI
975typename vector<_Tp, _Allocator>::size_type
976vector<_Tp, _Allocator>::__recommend(size_type __new_size) const
977{
978    const size_type __ms = max_size();
979    if (__new_size > __ms)
980        this->__throw_length_error();
981    const size_type __cap = capacity();
982    if (__cap >= __ms / 2)
983        return __ms;
984    return std::max<size_type>(2 * __cap, __new_size);
985}
986
987//  Default constructs __n objects starting at __end_
988//  throws if construction throws
989//  Precondition:  __n > 0
990//  Precondition:  size() + __n <= capacity()
991//  Postcondition:  size() == size() + __n
992template <class _Tp, class _Allocator>
993_LIBCPP_CONSTEXPR_SINCE_CXX20
994void
995vector<_Tp, _Allocator>::__construct_at_end(size_type __n)
996{
997    _ConstructTransaction __tx(*this, __n);
998    const_pointer __new_end = __tx.__new_end_;
999    for (pointer __pos = __tx.__pos_; __pos != __new_end; __tx.__pos_ = ++__pos) {
1000        __alloc_traits::construct(this->__alloc(), std::__to_address(__pos));
1001    }
1002}
1003
1004//  Copy constructs __n objects starting at __end_ from __x
1005//  throws if construction throws
1006//  Precondition:  __n > 0
1007//  Precondition:  size() + __n <= capacity()
1008//  Postcondition:  size() == old size() + __n
1009//  Postcondition:  [i] == __x for all i in [size() - __n, __n)
1010template <class _Tp, class _Allocator>
1011_LIBCPP_CONSTEXPR_SINCE_CXX20
1012inline
1013void
1014vector<_Tp, _Allocator>::__construct_at_end(size_type __n, const_reference __x)
1015{
1016    _ConstructTransaction __tx(*this, __n);
1017    const_pointer __new_end = __tx.__new_end_;
1018    for (pointer __pos = __tx.__pos_; __pos != __new_end; __tx.__pos_ = ++__pos) {
1019        __alloc_traits::construct(this->__alloc(), std::__to_address(__pos), __x);
1020    }
1021}
1022
1023template <class _Tp, class _Allocator>
1024template <class _ForwardIterator, __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value, int> >
1025_LIBCPP_CONSTEXPR_SINCE_CXX20 void
1026vector<_Tp, _Allocator>::__construct_at_end(_ForwardIterator __first, _ForwardIterator __last, size_type __n)
1027{
1028  _ConstructTransaction __tx(*this, __n);
1029  __tx.__pos_ = std::__uninitialized_allocator_copy(__alloc(), __first, __last, __tx.__pos_);
1030}
1031
1032//  Default constructs __n objects starting at __end_
1033//  throws if construction throws
1034//  Postcondition:  size() == size() + __n
1035//  Exception safety: strong.
1036template <class _Tp, class _Allocator>
1037_LIBCPP_CONSTEXPR_SINCE_CXX20
1038void
1039vector<_Tp, _Allocator>::__append(size_type __n)
1040{
1041    if (static_cast<size_type>(this->__end_cap() - this->__end_) >= __n)
1042        this->__construct_at_end(__n);
1043    else
1044    {
1045        allocator_type& __a = this->__alloc();
1046        __split_buffer<value_type, allocator_type&> __v(__recommend(size() + __n), size(), __a);
1047        __v.__construct_at_end(__n);
1048        __swap_out_circular_buffer(__v);
1049    }
1050}
1051
1052//  Default constructs __n objects starting at __end_
1053//  throws if construction throws
1054//  Postcondition:  size() == size() + __n
1055//  Exception safety: strong.
1056template <class _Tp, class _Allocator>
1057_LIBCPP_CONSTEXPR_SINCE_CXX20
1058void
1059vector<_Tp, _Allocator>::__append(size_type __n, const_reference __x)
1060{
1061    if (static_cast<size_type>(this->__end_cap() - this->__end_) >= __n)
1062        this->__construct_at_end(__n, __x);
1063    else
1064    {
1065        allocator_type& __a = this->__alloc();
1066        __split_buffer<value_type, allocator_type&> __v(__recommend(size() + __n), size(), __a);
1067        __v.__construct_at_end(__n, __x);
1068        __swap_out_circular_buffer(__v);
1069    }
1070}
1071
1072template <class _Tp, class _Allocator>
1073_LIBCPP_CONSTEXPR_SINCE_CXX20
1074vector<_Tp, _Allocator>::vector(size_type __n)
1075{
1076    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1077    std::__debug_db_insert_c(this);
1078    if (__n > 0)
1079    {
1080        __vallocate(__n);
1081        __construct_at_end(__n);
1082    }
1083    __guard.__complete();
1084}
1085
1086#if _LIBCPP_STD_VER > 11
1087template <class _Tp, class _Allocator>
1088_LIBCPP_CONSTEXPR_SINCE_CXX20
1089vector<_Tp, _Allocator>::vector(size_type __n, const allocator_type& __a)
1090    : __end_cap_(nullptr, __a)
1091{
1092    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1093    std::__debug_db_insert_c(this);
1094    if (__n > 0)
1095    {
1096        __vallocate(__n);
1097        __construct_at_end(__n);
1098    }
1099    __guard.__complete();
1100}
1101#endif
1102
1103template <class _Tp, class _Allocator>
1104_LIBCPP_CONSTEXPR_SINCE_CXX20
1105vector<_Tp, _Allocator>::vector(size_type __n, const value_type& __x)
1106{
1107    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1108    std::__debug_db_insert_c(this);
1109    if (__n > 0)
1110    {
1111        __vallocate(__n);
1112        __construct_at_end(__n, __x);
1113    }
1114    __guard.__complete();
1115}
1116
1117template <class _Tp, class _Allocator>
1118template <class _InputIterator, __enable_if_t<__is_exactly_cpp17_input_iterator<_InputIterator>::value &&
1119                              is_constructible<_Tp, typename iterator_traits<_InputIterator>::reference>::value,
1120                          int> >
1121_LIBCPP_CONSTEXPR_SINCE_CXX20
1122vector<_Tp, _Allocator>::vector(_InputIterator __first, _InputIterator __last)
1123{
1124    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1125    std::__debug_db_insert_c(this);
1126    for (; __first != __last; ++__first)
1127        emplace_back(*__first);
1128    __guard.__complete();
1129}
1130
1131template <class _Tp, class _Allocator>
1132template <class _InputIterator, __enable_if_t<__is_exactly_cpp17_input_iterator<_InputIterator>::value &&
1133                              is_constructible<_Tp, typename iterator_traits<_InputIterator>::reference>::value,
1134                          int> >
1135_LIBCPP_CONSTEXPR_SINCE_CXX20
1136vector<_Tp, _Allocator>::vector(_InputIterator __first, _InputIterator __last, const allocator_type& __a)
1137    : __end_cap_(nullptr, __a)
1138{
1139    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1140    std::__debug_db_insert_c(this);
1141    for (; __first != __last; ++__first)
1142        emplace_back(*__first);
1143    __guard.__complete();
1144}
1145
1146template <class _Tp, class _Allocator>
1147template <class _ForwardIterator, __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value &&
1148                        is_constructible<_Tp, typename iterator_traits<_ForwardIterator>::reference>::value,
1149                    int> >
1150_LIBCPP_CONSTEXPR_SINCE_CXX20
1151vector<_Tp, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last)
1152{
1153    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1154    std::__debug_db_insert_c(this);
1155    size_type __n = static_cast<size_type>(std::distance(__first, __last));
1156    if (__n > 0)
1157    {
1158        __vallocate(__n);
1159        __construct_at_end(__first, __last, __n);
1160    }
1161    __guard.__complete();
1162}
1163
1164template <class _Tp, class _Allocator>
1165template <class _ForwardIterator, __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value &&
1166                        is_constructible<_Tp, typename iterator_traits<_ForwardIterator>::reference>::value,
1167                    int> >
1168_LIBCPP_CONSTEXPR_SINCE_CXX20
1169vector<_Tp, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last, const allocator_type& __a)
1170    : __end_cap_(nullptr, __a)
1171{
1172    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1173    std::__debug_db_insert_c(this);
1174    size_type __n = static_cast<size_type>(std::distance(__first, __last));
1175    if (__n > 0)
1176    {
1177        __vallocate(__n);
1178        __construct_at_end(__first, __last, __n);
1179    }
1180    __guard.__complete();
1181}
1182
1183template <class _Tp, class _Allocator>
1184_LIBCPP_CONSTEXPR_SINCE_CXX20
1185vector<_Tp, _Allocator>::vector(const vector& __x)
1186    : __end_cap_(nullptr, __alloc_traits::select_on_container_copy_construction(__x.__alloc()))
1187{
1188    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1189    std::__debug_db_insert_c(this);
1190    size_type __n = __x.size();
1191    if (__n > 0)
1192    {
1193        __vallocate(__n);
1194        __construct_at_end(__x.__begin_, __x.__end_, __n);
1195    }
1196    __guard.__complete();
1197}
1198
1199template <class _Tp, class _Allocator>
1200_LIBCPP_CONSTEXPR_SINCE_CXX20
1201vector<_Tp, _Allocator>::vector(const vector& __x, const __type_identity_t<allocator_type>& __a)
1202    : __end_cap_(nullptr, __a)
1203{
1204    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1205    std::__debug_db_insert_c(this);
1206    size_type __n = __x.size();
1207    if (__n > 0)
1208    {
1209        __vallocate(__n);
1210        __construct_at_end(__x.__begin_, __x.__end_, __n);
1211    }
1212    __guard.__complete();
1213}
1214
1215template <class _Tp, class _Allocator>
1216_LIBCPP_CONSTEXPR_SINCE_CXX20
1217inline _LIBCPP_HIDE_FROM_ABI
1218vector<_Tp, _Allocator>::vector(vector&& __x)
1219#if _LIBCPP_STD_VER > 14
1220        noexcept
1221#else
1222        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
1223#endif
1224    : __end_cap_(nullptr, std::move(__x.__alloc()))
1225{
1226    std::__debug_db_insert_c(this);
1227    std::__debug_db_swap(this, std::addressof(__x));
1228    this->__begin_ = __x.__begin_;
1229    this->__end_ = __x.__end_;
1230    this->__end_cap() = __x.__end_cap();
1231    __x.__begin_ = __x.__end_ = __x.__end_cap() = nullptr;
1232}
1233
1234template <class _Tp, class _Allocator>
1235_LIBCPP_CONSTEXPR_SINCE_CXX20
1236inline _LIBCPP_HIDE_FROM_ABI
1237vector<_Tp, _Allocator>::vector(vector&& __x, const __type_identity_t<allocator_type>& __a)
1238    : __end_cap_(nullptr, __a)
1239{
1240    std::__debug_db_insert_c(this);
1241    if (__a == __x.__alloc())
1242    {
1243        this->__begin_ = __x.__begin_;
1244        this->__end_ = __x.__end_;
1245        this->__end_cap() = __x.__end_cap();
1246        __x.__begin_ = __x.__end_ = __x.__end_cap() = nullptr;
1247        std::__debug_db_swap(this, std::addressof(__x));
1248    }
1249    else
1250    {
1251        typedef move_iterator<iterator> _Ip;
1252        auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1253        assign(_Ip(__x.begin()), _Ip(__x.end()));
1254        __guard.__complete();
1255    }
1256}
1257
1258#ifndef _LIBCPP_CXX03_LANG
1259
1260template <class _Tp, class _Allocator>
1261_LIBCPP_CONSTEXPR_SINCE_CXX20
1262inline _LIBCPP_HIDE_FROM_ABI
1263vector<_Tp, _Allocator>::vector(initializer_list<value_type> __il)
1264{
1265    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1266    std::__debug_db_insert_c(this);
1267    if (__il.size() > 0)
1268    {
1269        __vallocate(__il.size());
1270        __construct_at_end(__il.begin(), __il.end(), __il.size());
1271    }
1272    __guard.__complete();
1273}
1274
1275template <class _Tp, class _Allocator>
1276_LIBCPP_CONSTEXPR_SINCE_CXX20
1277inline _LIBCPP_HIDE_FROM_ABI
1278vector<_Tp, _Allocator>::vector(initializer_list<value_type> __il, const allocator_type& __a)
1279    : __end_cap_(nullptr, __a)
1280{
1281    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
1282    std::__debug_db_insert_c(this);
1283    if (__il.size() > 0)
1284    {
1285        __vallocate(__il.size());
1286        __construct_at_end(__il.begin(), __il.end(), __il.size());
1287    }
1288    __guard.__complete();
1289}
1290
1291#endif // _LIBCPP_CXX03_LANG
1292
1293template <class _Tp, class _Allocator>
1294_LIBCPP_CONSTEXPR_SINCE_CXX20
1295inline _LIBCPP_HIDE_FROM_ABI
1296vector<_Tp, _Allocator>&
1297vector<_Tp, _Allocator>::operator=(vector&& __x)
1298    _NOEXCEPT_((__noexcept_move_assign_container<_Allocator, __alloc_traits>::value))
1299{
1300    __move_assign(__x, integral_constant<bool,
1301          __alloc_traits::propagate_on_container_move_assignment::value>());
1302    return *this;
1303}
1304
1305template <class _Tp, class _Allocator>
1306_LIBCPP_CONSTEXPR_SINCE_CXX20
1307void
1308vector<_Tp, _Allocator>::__move_assign(vector& __c, false_type)
1309    _NOEXCEPT_(__alloc_traits::is_always_equal::value)
1310{
1311    if (__alloc() != __c.__alloc())
1312    {
1313        typedef move_iterator<iterator> _Ip;
1314        assign(_Ip(__c.begin()), _Ip(__c.end()));
1315    }
1316    else
1317        __move_assign(__c, true_type());
1318}
1319
1320template <class _Tp, class _Allocator>
1321_LIBCPP_CONSTEXPR_SINCE_CXX20
1322void
1323vector<_Tp, _Allocator>::__move_assign(vector& __c, true_type)
1324    _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
1325{
1326    __vdeallocate();
1327    __move_assign_alloc(__c); // this can throw
1328    this->__begin_ = __c.__begin_;
1329    this->__end_ = __c.__end_;
1330    this->__end_cap() = __c.__end_cap();
1331    __c.__begin_ = __c.__end_ = __c.__end_cap() = nullptr;
1332    std::__debug_db_swap(this, std::addressof(__c));
1333}
1334
1335template <class _Tp, class _Allocator>
1336_LIBCPP_CONSTEXPR_SINCE_CXX20
1337inline _LIBCPP_HIDE_FROM_ABI
1338vector<_Tp, _Allocator>&
1339vector<_Tp, _Allocator>::operator=(const vector& __x)
1340{
1341    if (this != std::addressof(__x))
1342    {
1343        __copy_assign_alloc(__x);
1344        assign(__x.__begin_, __x.__end_);
1345    }
1346    return *this;
1347}
1348
1349template <class _Tp, class _Allocator>
1350template <class _InputIterator, __enable_if_t<__is_exactly_cpp17_input_iterator<_InputIterator>::value &&
1351                              is_constructible<_Tp, typename iterator_traits<_InputIterator>::reference>::value,
1352                          int> >
1353_LIBCPP_CONSTEXPR_SINCE_CXX20 void
1354vector<_Tp, _Allocator>::assign(_InputIterator __first, _InputIterator __last)
1355{
1356    clear();
1357    for (; __first != __last; ++__first)
1358        emplace_back(*__first);
1359}
1360
1361template <class _Tp, class _Allocator>
1362template <class _ForwardIterator, __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value &&
1363                        is_constructible<_Tp, typename iterator_traits<_ForwardIterator>::reference>::value,
1364                    int> >
1365_LIBCPP_CONSTEXPR_SINCE_CXX20 void
1366vector<_Tp, _Allocator>::assign(_ForwardIterator __first, _ForwardIterator __last)
1367{
1368    size_type __new_size = static_cast<size_type>(std::distance(__first, __last));
1369    if (__new_size <= capacity())
1370    {
1371        _ForwardIterator __mid = __last;
1372        bool __growing = false;
1373        if (__new_size > size())
1374        {
1375            __growing = true;
1376            __mid =  __first;
1377            std::advance(__mid, size());
1378        }
1379        pointer __m = std::copy(__first, __mid, this->__begin_);
1380        if (__growing)
1381            __construct_at_end(__mid, __last, __new_size - size());
1382        else
1383            this->__destruct_at_end(__m);
1384    }
1385    else
1386    {
1387        __vdeallocate();
1388        __vallocate(__recommend(__new_size));
1389        __construct_at_end(__first, __last, __new_size);
1390    }
1391    std::__debug_db_invalidate_all(this);
1392}
1393
1394template <class _Tp, class _Allocator>
1395_LIBCPP_CONSTEXPR_SINCE_CXX20
1396void
1397vector<_Tp, _Allocator>::assign(size_type __n, const_reference __u)
1398{
1399    if (__n <= capacity())
1400    {
1401        size_type __s = size();
1402        std::fill_n(this->__begin_, std::min(__n, __s), __u);
1403        if (__n > __s)
1404            __construct_at_end(__n - __s, __u);
1405        else
1406            this->__destruct_at_end(this->__begin_ + __n);
1407    }
1408    else
1409    {
1410        __vdeallocate();
1411        __vallocate(__recommend(static_cast<size_type>(__n)));
1412        __construct_at_end(__n, __u);
1413    }
1414    std::__debug_db_invalidate_all(this);
1415}
1416
1417template <class _Tp, class _Allocator>
1418_LIBCPP_CONSTEXPR_SINCE_CXX20
1419inline _LIBCPP_HIDE_FROM_ABI
1420typename vector<_Tp, _Allocator>::iterator
1421vector<_Tp, _Allocator>::begin() _NOEXCEPT
1422{
1423    return __make_iter(this->__begin_);
1424}
1425
1426template <class _Tp, class _Allocator>
1427_LIBCPP_CONSTEXPR_SINCE_CXX20
1428inline _LIBCPP_HIDE_FROM_ABI
1429typename vector<_Tp, _Allocator>::const_iterator
1430vector<_Tp, _Allocator>::begin() const _NOEXCEPT
1431{
1432    return __make_iter(this->__begin_);
1433}
1434
1435template <class _Tp, class _Allocator>
1436_LIBCPP_CONSTEXPR_SINCE_CXX20
1437inline _LIBCPP_HIDE_FROM_ABI
1438typename vector<_Tp, _Allocator>::iterator
1439vector<_Tp, _Allocator>::end() _NOEXCEPT
1440{
1441    return __make_iter(this->__end_);
1442}
1443
1444template <class _Tp, class _Allocator>
1445_LIBCPP_CONSTEXPR_SINCE_CXX20
1446inline _LIBCPP_HIDE_FROM_ABI
1447typename vector<_Tp, _Allocator>::const_iterator
1448vector<_Tp, _Allocator>::end() const _NOEXCEPT
1449{
1450    return __make_iter(this->__end_);
1451}
1452
1453template <class _Tp, class _Allocator>
1454_LIBCPP_CONSTEXPR_SINCE_CXX20
1455inline _LIBCPP_HIDE_FROM_ABI
1456typename vector<_Tp, _Allocator>::reference
1457vector<_Tp, _Allocator>::operator[](size_type __n) _NOEXCEPT
1458{
1459    _LIBCPP_ASSERT(__n < size(), "vector[] index out of bounds");
1460    return this->__begin_[__n];
1461}
1462
1463template <class _Tp, class _Allocator>
1464_LIBCPP_CONSTEXPR_SINCE_CXX20
1465inline _LIBCPP_HIDE_FROM_ABI
1466typename vector<_Tp, _Allocator>::const_reference
1467vector<_Tp, _Allocator>::operator[](size_type __n) const _NOEXCEPT
1468{
1469    _LIBCPP_ASSERT(__n < size(), "vector[] index out of bounds");
1470    return this->__begin_[__n];
1471}
1472
1473template <class _Tp, class _Allocator>
1474_LIBCPP_CONSTEXPR_SINCE_CXX20
1475typename vector<_Tp, _Allocator>::reference
1476vector<_Tp, _Allocator>::at(size_type __n)
1477{
1478    if (__n >= size())
1479        this->__throw_out_of_range();
1480    return this->__begin_[__n];
1481}
1482
1483template <class _Tp, class _Allocator>
1484_LIBCPP_CONSTEXPR_SINCE_CXX20
1485typename vector<_Tp, _Allocator>::const_reference
1486vector<_Tp, _Allocator>::at(size_type __n) const
1487{
1488    if (__n >= size())
1489        this->__throw_out_of_range();
1490    return this->__begin_[__n];
1491}
1492
1493template <class _Tp, class _Allocator>
1494_LIBCPP_CONSTEXPR_SINCE_CXX20
1495void
1496vector<_Tp, _Allocator>::reserve(size_type __n)
1497{
1498    if (__n > capacity())
1499    {
1500        if (__n > max_size())
1501            this->__throw_length_error();
1502        allocator_type& __a = this->__alloc();
1503        __split_buffer<value_type, allocator_type&> __v(__n, size(), __a);
1504        __swap_out_circular_buffer(__v);
1505    }
1506}
1507
1508template <class _Tp, class _Allocator>
1509_LIBCPP_CONSTEXPR_SINCE_CXX20
1510void
1511vector<_Tp, _Allocator>::shrink_to_fit() _NOEXCEPT
1512{
1513    if (capacity() > size())
1514    {
1515#ifndef _LIBCPP_NO_EXCEPTIONS
1516        try
1517        {
1518#endif // _LIBCPP_NO_EXCEPTIONS
1519            allocator_type& __a = this->__alloc();
1520            __split_buffer<value_type, allocator_type&> __v(size(), size(), __a);
1521            __swap_out_circular_buffer(__v);
1522#ifndef _LIBCPP_NO_EXCEPTIONS
1523        }
1524        catch (...)
1525        {
1526        }
1527#endif // _LIBCPP_NO_EXCEPTIONS
1528    }
1529}
1530
1531template <class _Tp, class _Allocator>
1532template <class _Up>
1533_LIBCPP_CONSTEXPR_SINCE_CXX20
1534void
1535vector<_Tp, _Allocator>::__push_back_slow_path(_Up&& __x)
1536{
1537    allocator_type& __a = this->__alloc();
1538    __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), size(), __a);
1539    // __v.push_back(std::forward<_Up>(__x));
1540    __alloc_traits::construct(__a, std::__to_address(__v.__end_), std::forward<_Up>(__x));
1541    __v.__end_++;
1542    __swap_out_circular_buffer(__v);
1543}
1544
1545template <class _Tp, class _Allocator>
1546_LIBCPP_CONSTEXPR_SINCE_CXX20
1547inline _LIBCPP_HIDE_FROM_ABI
1548void
1549vector<_Tp, _Allocator>::push_back(const_reference __x)
1550{
1551    if (this->__end_ != this->__end_cap())
1552    {
1553        __construct_one_at_end(__x);
1554    }
1555    else
1556        __push_back_slow_path(__x);
1557}
1558
1559template <class _Tp, class _Allocator>
1560_LIBCPP_CONSTEXPR_SINCE_CXX20
1561inline _LIBCPP_HIDE_FROM_ABI
1562void
1563vector<_Tp, _Allocator>::push_back(value_type&& __x)
1564{
1565    if (this->__end_ < this->__end_cap())
1566    {
1567        __construct_one_at_end(std::move(__x));
1568    }
1569    else
1570        __push_back_slow_path(std::move(__x));
1571}
1572
1573template <class _Tp, class _Allocator>
1574template <class... _Args>
1575_LIBCPP_CONSTEXPR_SINCE_CXX20
1576void
1577vector<_Tp, _Allocator>::__emplace_back_slow_path(_Args&&... __args)
1578{
1579    allocator_type& __a = this->__alloc();
1580    __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), size(), __a);
1581//    __v.emplace_back(std::forward<_Args>(__args)...);
1582    __alloc_traits::construct(__a, std::__to_address(__v.__end_), std::forward<_Args>(__args)...);
1583    __v.__end_++;
1584    __swap_out_circular_buffer(__v);
1585}
1586
1587template <class _Tp, class _Allocator>
1588template <class... _Args>
1589_LIBCPP_CONSTEXPR_SINCE_CXX20
1590inline
1591#if _LIBCPP_STD_VER > 14
1592typename vector<_Tp, _Allocator>::reference
1593#else
1594void
1595#endif
1596vector<_Tp, _Allocator>::emplace_back(_Args&&... __args)
1597{
1598    if (this->__end_ < this->__end_cap())
1599    {
1600        __construct_one_at_end(std::forward<_Args>(__args)...);
1601    }
1602    else
1603        __emplace_back_slow_path(std::forward<_Args>(__args)...);
1604#if _LIBCPP_STD_VER > 14
1605    return this->back();
1606#endif
1607}
1608
1609template <class _Tp, class _Allocator>
1610_LIBCPP_CONSTEXPR_SINCE_CXX20
1611inline
1612void
1613vector<_Tp, _Allocator>::pop_back()
1614{
1615    _LIBCPP_ASSERT(!empty(), "vector::pop_back called on an empty vector");
1616    this->__destruct_at_end(this->__end_ - 1);
1617}
1618
1619template <class _Tp, class _Allocator>
1620_LIBCPP_CONSTEXPR_SINCE_CXX20
1621inline _LIBCPP_HIDE_FROM_ABI
1622typename vector<_Tp, _Allocator>::iterator
1623vector<_Tp, _Allocator>::erase(const_iterator __position)
1624{
1625    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
1626                         "vector::erase(iterator) called with an iterator not referring to this vector");
1627    _LIBCPP_ASSERT(__position != end(),
1628        "vector::erase(iterator) called with a non-dereferenceable iterator");
1629    difference_type __ps = __position - cbegin();
1630    pointer __p = this->__begin_ + __ps;
1631    this->__destruct_at_end(std::move(__p + 1, this->__end_, __p));
1632    if (!__libcpp_is_constant_evaluated())
1633        this->__invalidate_iterators_past(__p - 1);
1634    return __make_iter(__p);
1635}
1636
1637template <class _Tp, class _Allocator>
1638_LIBCPP_CONSTEXPR_SINCE_CXX20
1639typename vector<_Tp, _Allocator>::iterator
1640vector<_Tp, _Allocator>::erase(const_iterator __first, const_iterator __last)
1641{
1642    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__first)) == this,
1643                         "vector::erase(iterator, iterator) called with an iterator not referring to this vector");
1644    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__last)) == this,
1645                         "vector::erase(iterator, iterator) called with an iterator not referring to this vector");
1646
1647    _LIBCPP_ASSERT(__first <= __last, "vector::erase(first, last) called with invalid range");
1648    pointer __p = this->__begin_ + (__first - begin());
1649    if (__first != __last) {
1650        this->__destruct_at_end(std::move(__p + (__last - __first), this->__end_, __p));
1651        if (!__libcpp_is_constant_evaluated())
1652            this->__invalidate_iterators_past(__p - 1);
1653    }
1654    return __make_iter(__p);
1655}
1656
1657template <class _Tp, class _Allocator>
1658_LIBCPP_CONSTEXPR_SINCE_CXX20
1659void
1660vector<_Tp, _Allocator>::__move_range(pointer __from_s, pointer __from_e, pointer __to)
1661{
1662    pointer __old_last = this->__end_;
1663    difference_type __n = __old_last - __to;
1664    {
1665      pointer __i = __from_s + __n;
1666      _ConstructTransaction __tx(*this, __from_e - __i);
1667      for (pointer __pos = __tx.__pos_; __i < __from_e;
1668           ++__i, (void) ++__pos, __tx.__pos_ = __pos) {
1669          __alloc_traits::construct(this->__alloc(),
1670                                    std::__to_address(__pos),
1671                                    std::move(*__i));
1672      }
1673    }
1674    std::move_backward(__from_s, __from_s + __n, __old_last);
1675}
1676
1677template <class _Tp, class _Allocator>
1678_LIBCPP_CONSTEXPR_SINCE_CXX20
1679typename vector<_Tp, _Allocator>::iterator
1680vector<_Tp, _Allocator>::insert(const_iterator __position, const_reference __x)
1681{
1682    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
1683                         "vector::insert(iterator, x) called with an iterator not referring to this vector");
1684    pointer __p = this->__begin_ + (__position - begin());
1685    // We can't compare unrelated pointers inside constant expressions
1686    if (!__libcpp_is_constant_evaluated() && this->__end_ < this->__end_cap())
1687    {
1688        if (__p == this->__end_)
1689        {
1690            __construct_one_at_end(__x);
1691        }
1692        else
1693        {
1694            __move_range(__p, this->__end_, __p + 1);
1695            const_pointer __xr = pointer_traits<const_pointer>::pointer_to(__x);
1696            if (__p <= __xr && __xr < this->__end_)
1697                ++__xr;
1698            *__p = *__xr;
1699        }
1700    }
1701    else
1702    {
1703        allocator_type& __a = this->__alloc();
1704        __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), __p - this->__begin_, __a);
1705        __v.push_back(__x);
1706        __p = __swap_out_circular_buffer(__v, __p);
1707    }
1708    return __make_iter(__p);
1709}
1710
1711template <class _Tp, class _Allocator>
1712_LIBCPP_CONSTEXPR_SINCE_CXX20
1713typename vector<_Tp, _Allocator>::iterator
1714vector<_Tp, _Allocator>::insert(const_iterator __position, value_type&& __x)
1715{
1716    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
1717                         "vector::insert(iterator, x) called with an iterator not referring to this vector");
1718    pointer __p = this->__begin_ + (__position - begin());
1719    if (this->__end_ < this->__end_cap())
1720    {
1721        if (__p == this->__end_)
1722        {
1723            __construct_one_at_end(std::move(__x));
1724        }
1725        else
1726        {
1727            __move_range(__p, this->__end_, __p + 1);
1728            *__p = std::move(__x);
1729        }
1730    }
1731    else
1732    {
1733        allocator_type& __a = this->__alloc();
1734        __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), __p - this->__begin_, __a);
1735        __v.push_back(std::move(__x));
1736        __p = __swap_out_circular_buffer(__v, __p);
1737    }
1738    return __make_iter(__p);
1739}
1740
1741template <class _Tp, class _Allocator>
1742template <class... _Args>
1743_LIBCPP_CONSTEXPR_SINCE_CXX20
1744typename vector<_Tp, _Allocator>::iterator
1745vector<_Tp, _Allocator>::emplace(const_iterator __position, _Args&&... __args)
1746{
1747    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
1748                         "vector::emplace(iterator, x) called with an iterator not referring to this vector");
1749    pointer __p = this->__begin_ + (__position - begin());
1750    if (this->__end_ < this->__end_cap())
1751    {
1752        if (__p == this->__end_)
1753        {
1754            __construct_one_at_end(std::forward<_Args>(__args)...);
1755        }
1756        else
1757        {
1758            __temp_value<value_type, _Allocator> __tmp(this->__alloc(), std::forward<_Args>(__args)...);
1759            __move_range(__p, this->__end_, __p + 1);
1760            *__p = std::move(__tmp.get());
1761        }
1762    }
1763    else
1764    {
1765        allocator_type& __a = this->__alloc();
1766        __split_buffer<value_type, allocator_type&> __v(__recommend(size() + 1), __p - this->__begin_, __a);
1767        __v.emplace_back(std::forward<_Args>(__args)...);
1768        __p = __swap_out_circular_buffer(__v, __p);
1769    }
1770    return __make_iter(__p);
1771}
1772
1773template <class _Tp, class _Allocator>
1774_LIBCPP_CONSTEXPR_SINCE_CXX20
1775typename vector<_Tp, _Allocator>::iterator
1776vector<_Tp, _Allocator>::insert(const_iterator __position, size_type __n, const_reference __x)
1777{
1778    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
1779                         "vector::insert(iterator, n, x) called with an iterator not referring to this vector");
1780    pointer __p = this->__begin_ + (__position - begin());
1781    if (__n > 0)
1782    {
1783        // We can't compare unrelated pointers inside constant expressions
1784        if (!__libcpp_is_constant_evaluated() && __n <= static_cast<size_type>(this->__end_cap() - this->__end_))
1785        {
1786            size_type __old_n = __n;
1787            pointer __old_last = this->__end_;
1788            if (__n > static_cast<size_type>(this->__end_ - __p))
1789            {
1790                size_type __cx = __n - (this->__end_ - __p);
1791                __construct_at_end(__cx, __x);
1792                __n -= __cx;
1793            }
1794            if (__n > 0)
1795            {
1796                __move_range(__p, __old_last, __p + __old_n);
1797                const_pointer __xr = pointer_traits<const_pointer>::pointer_to(__x);
1798                if (__p <= __xr && __xr < this->__end_)
1799                    __xr += __old_n;
1800                std::fill_n(__p, __n, *__xr);
1801            }
1802        }
1803        else
1804        {
1805            allocator_type& __a = this->__alloc();
1806            __split_buffer<value_type, allocator_type&> __v(__recommend(size() + __n), __p - this->__begin_, __a);
1807            __v.__construct_at_end(__n, __x);
1808            __p = __swap_out_circular_buffer(__v, __p);
1809        }
1810    }
1811    return __make_iter(__p);
1812}
1813
1814template <class _Tp, class _Allocator>
1815template <class _InputIterator, __enable_if_t<__is_exactly_cpp17_input_iterator<_InputIterator>::value &&
1816                              is_constructible<_Tp, typename iterator_traits<_InputIterator>::reference>::value,
1817                          int> >
1818_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::iterator
1819vector<_Tp, _Allocator>::insert(const_iterator __position, _InputIterator __first, _InputIterator __last)
1820{
1821    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
1822                         "vector::insert(iterator, range) called with an iterator not referring to this vector");
1823    difference_type __off = __position - begin();
1824    pointer __p = this->__begin_ + __off;
1825    allocator_type& __a = this->__alloc();
1826    pointer __old_last = this->__end_;
1827    for (; this->__end_ != this->__end_cap() && __first != __last; ++__first)
1828    {
1829        __construct_one_at_end(*__first);
1830    }
1831    __split_buffer<value_type, allocator_type&> __v(__a);
1832    if (__first != __last)
1833    {
1834#ifndef _LIBCPP_NO_EXCEPTIONS
1835        try
1836        {
1837#endif // _LIBCPP_NO_EXCEPTIONS
1838            __v.__construct_at_end(__first, __last);
1839            difference_type __old_size = __old_last - this->__begin_;
1840            difference_type __old_p = __p - this->__begin_;
1841            reserve(__recommend(size() + __v.size()));
1842            __p = this->__begin_ + __old_p;
1843            __old_last = this->__begin_ + __old_size;
1844#ifndef _LIBCPP_NO_EXCEPTIONS
1845        }
1846        catch (...)
1847        {
1848            erase(__make_iter(__old_last), end());
1849            throw;
1850        }
1851#endif // _LIBCPP_NO_EXCEPTIONS
1852    }
1853    __p = std::rotate(__p, __old_last, this->__end_);
1854    insert(__make_iter(__p), std::make_move_iterator(__v.begin()),
1855                             std::make_move_iterator(__v.end()));
1856    return begin() + __off;
1857}
1858
1859template <class _Tp, class _Allocator>
1860template <class _ForwardIterator, __enable_if_t<__is_cpp17_forward_iterator<_ForwardIterator>::value &&
1861                        is_constructible<_Tp, typename iterator_traits<_ForwardIterator>::reference>::value,
1862                    int> >
1863_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<_Tp, _Allocator>::iterator
1864vector<_Tp, _Allocator>::insert(const_iterator __position, _ForwardIterator __first, _ForwardIterator __last)
1865{
1866    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
1867                         "vector::insert(iterator, range) called with an iterator not referring to this vector");
1868    pointer __p = this->__begin_ + (__position - begin());
1869    difference_type __n = std::distance(__first, __last);
1870    if (__n > 0)
1871    {
1872        if (__n <= this->__end_cap() - this->__end_)
1873        {
1874            size_type __old_n = __n;
1875            pointer __old_last = this->__end_;
1876            _ForwardIterator __m = __last;
1877            difference_type __dx = this->__end_ - __p;
1878            if (__n > __dx)
1879            {
1880                __m = __first;
1881                difference_type __diff = this->__end_ - __p;
1882                std::advance(__m, __diff);
1883                __construct_at_end(__m, __last, __n - __diff);
1884                __n = __dx;
1885            }
1886            if (__n > 0)
1887            {
1888                __move_range(__p, __old_last, __p + __old_n);
1889                std::copy(__first, __m, __p);
1890            }
1891        }
1892        else
1893        {
1894            allocator_type& __a = this->__alloc();
1895            __split_buffer<value_type, allocator_type&> __v(__recommend(size() + __n), __p - this->__begin_, __a);
1896            __v.__construct_at_end(__first, __last);
1897            __p = __swap_out_circular_buffer(__v, __p);
1898        }
1899    }
1900    return __make_iter(__p);
1901}
1902
1903template <class _Tp, class _Allocator>
1904_LIBCPP_CONSTEXPR_SINCE_CXX20
1905void
1906vector<_Tp, _Allocator>::resize(size_type __sz)
1907{
1908    size_type __cs = size();
1909    if (__cs < __sz)
1910        this->__append(__sz - __cs);
1911    else if (__cs > __sz)
1912        this->__destruct_at_end(this->__begin_ + __sz);
1913}
1914
1915template <class _Tp, class _Allocator>
1916_LIBCPP_CONSTEXPR_SINCE_CXX20
1917void
1918vector<_Tp, _Allocator>::resize(size_type __sz, const_reference __x)
1919{
1920    size_type __cs = size();
1921    if (__cs < __sz)
1922        this->__append(__sz - __cs, __x);
1923    else if (__cs > __sz)
1924        this->__destruct_at_end(this->__begin_ + __sz);
1925}
1926
1927template <class _Tp, class _Allocator>
1928_LIBCPP_CONSTEXPR_SINCE_CXX20
1929void
1930vector<_Tp, _Allocator>::swap(vector& __x)
1931#if _LIBCPP_STD_VER >= 14
1932    _NOEXCEPT
1933#else
1934    _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
1935                __is_nothrow_swappable<allocator_type>::value)
1936#endif
1937{
1938    _LIBCPP_ASSERT(__alloc_traits::propagate_on_container_swap::value ||
1939                   this->__alloc() == __x.__alloc(),
1940                   "vector::swap: Either propagate_on_container_swap must be true"
1941                   " or the allocators must compare equal");
1942    std::swap(this->__begin_, __x.__begin_);
1943    std::swap(this->__end_, __x.__end_);
1944    std::swap(this->__end_cap(), __x.__end_cap());
1945    std::__swap_allocator(this->__alloc(), __x.__alloc(),
1946        integral_constant<bool,__alloc_traits::propagate_on_container_swap::value>());
1947    std::__debug_db_swap(this, std::addressof(__x));
1948}
1949
1950template <class _Tp, class _Allocator>
1951_LIBCPP_CONSTEXPR_SINCE_CXX20
1952bool
1953vector<_Tp, _Allocator>::__invariants() const
1954{
1955    if (this->__begin_ == nullptr)
1956    {
1957        if (this->__end_ != nullptr || this->__end_cap() != nullptr)
1958            return false;
1959    }
1960    else
1961    {
1962        if (this->__begin_ > this->__end_)
1963            return false;
1964        if (this->__begin_ == this->__end_cap())
1965            return false;
1966        if (this->__end_ > this->__end_cap())
1967            return false;
1968    }
1969    return true;
1970}
1971
1972#ifdef _LIBCPP_ENABLE_DEBUG_MODE
1973
1974template <class _Tp, class _Allocator>
1975bool
1976vector<_Tp, _Allocator>::__dereferenceable(const const_iterator* __i) const
1977{
1978    return this->__begin_ <= __i->base() && __i->base() < this->__end_;
1979}
1980
1981template <class _Tp, class _Allocator>
1982bool
1983vector<_Tp, _Allocator>::__decrementable(const const_iterator* __i) const
1984{
1985    return this->__begin_ < __i->base() && __i->base() <= this->__end_;
1986}
1987
1988template <class _Tp, class _Allocator>
1989bool
1990vector<_Tp, _Allocator>::__addable(const const_iterator* __i, ptrdiff_t __n) const
1991{
1992    const_pointer __p = __i->base() + __n;
1993    return this->__begin_ <= __p && __p <= this->__end_;
1994}
1995
1996template <class _Tp, class _Allocator>
1997bool
1998vector<_Tp, _Allocator>::__subscriptable(const const_iterator* __i, ptrdiff_t __n) const
1999{
2000    const_pointer __p = __i->base() + __n;
2001    return this->__begin_ <= __p && __p < this->__end_;
2002}
2003
2004#endif // _LIBCPP_ENABLE_DEBUG_MODE
2005
2006template <class _Tp, class _Allocator>
2007inline _LIBCPP_HIDE_FROM_ABI
2008void
2009vector<_Tp, _Allocator>::__invalidate_iterators_past(pointer __new_last) {
2010#ifdef _LIBCPP_ENABLE_DEBUG_MODE
2011  __c_node* __c = __get_db()->__find_c_and_lock(this);
2012  for (__i_node** __p = __c->end_; __p != __c->beg_; ) {
2013    --__p;
2014    const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
2015    if (__i->base() > __new_last) {
2016      (*__p)->__c_ = nullptr;
2017      if (--__c->end_ != __p)
2018        std::memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
2019    }
2020  }
2021  __get_db()->unlock();
2022#else
2023  ((void)__new_last);
2024#endif
2025}
2026
2027// vector<bool>
2028
2029template <class _Allocator> class vector<bool, _Allocator>;
2030
2031template <class _Allocator> struct hash<vector<bool, _Allocator> >;
2032
2033template <class _Allocator>
2034struct __has_storage_type<vector<bool, _Allocator> >
2035{
2036    static const bool value = true;
2037};
2038
2039template <class _Allocator>
2040class _LIBCPP_TEMPLATE_VIS vector<bool, _Allocator>
2041{
2042public:
2043    typedef vector                                   __self;
2044    typedef bool                                     value_type;
2045    typedef _Allocator                               allocator_type;
2046    typedef allocator_traits<allocator_type>         __alloc_traits;
2047    typedef typename __alloc_traits::size_type       size_type;
2048    typedef typename __alloc_traits::difference_type difference_type;
2049    typedef size_type __storage_type;
2050    typedef __bit_iterator<vector, false>            pointer;
2051    typedef __bit_iterator<vector, true>             const_pointer;
2052    typedef pointer                                  iterator;
2053    typedef const_pointer                            const_iterator;
2054    typedef std::reverse_iterator<iterator>         reverse_iterator;
2055    typedef std::reverse_iterator<const_iterator>   const_reverse_iterator;
2056
2057private:
2058    typedef __rebind_alloc<__alloc_traits, __storage_type> __storage_allocator;
2059    typedef allocator_traits<__storage_allocator>    __storage_traits;
2060    typedef typename __storage_traits::pointer       __storage_pointer;
2061    typedef typename __storage_traits::const_pointer __const_storage_pointer;
2062
2063    __storage_pointer                                      __begin_;
2064    size_type                                              __size_;
2065    __compressed_pair<size_type, __storage_allocator> __cap_alloc_;
2066public:
2067    typedef __bit_reference<vector>                  reference;
2068#ifdef _LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL
2069    using const_reference = bool;
2070#else
2071    typedef __bit_const_reference<vector>            const_reference;
2072#endif
2073private:
2074    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2075    size_type& __cap() _NOEXCEPT
2076        {return __cap_alloc_.first();}
2077    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2078    const size_type& __cap() const _NOEXCEPT
2079        {return __cap_alloc_.first();}
2080    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2081    __storage_allocator& __alloc() _NOEXCEPT
2082        {return __cap_alloc_.second();}
2083    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2084    const __storage_allocator& __alloc() const _NOEXCEPT
2085        {return __cap_alloc_.second();}
2086
2087    static const unsigned __bits_per_word = static_cast<unsigned>(sizeof(__storage_type) * CHAR_BIT);
2088
2089    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2090    static size_type __internal_cap_to_external(size_type __n) _NOEXCEPT
2091        {return __n * __bits_per_word;}
2092    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2093    static size_type __external_cap_to_internal(size_type __n) _NOEXCEPT
2094        {return (__n - 1) / __bits_per_word + 1;}
2095
2096public:
2097    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2098    vector() _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value);
2099
2100    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit vector(const allocator_type& __a)
2101#if _LIBCPP_STD_VER <= 14
2102        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value);
2103#else
2104        _NOEXCEPT;
2105#endif
2106
2107private:
2108  class __destroy_vector {
2109    public:
2110      _LIBCPP_CONSTEXPR __destroy_vector(vector& __vec) : __vec_(__vec) {}
2111
2112      _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void operator()() {
2113        if (__vec_.__begin_ != nullptr)
2114            __storage_traits::deallocate(__vec_.__alloc(), __vec_.__begin_, __vec_.__cap());
2115        std::__debug_db_invalidate_all(this);
2116      }
2117
2118    private:
2119      vector& __vec_;
2120  };
2121
2122public:
2123  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~vector() { __destroy_vector(*this)(); }
2124
2125    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit vector(size_type __n);
2126#if _LIBCPP_STD_VER > 11
2127    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit vector(size_type __n, const allocator_type& __a);
2128#endif
2129    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(size_type __n, const value_type& __v);
2130    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(size_type __n, const value_type& __v, const allocator_type& __a);
2131    template <class _InputIterator>
2132    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(_InputIterator __first, _InputIterator __last,
2133               typename enable_if<__is_exactly_cpp17_input_iterator<_InputIterator>::value>::type* = 0);
2134    template <class _InputIterator>
2135    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(_InputIterator __first, _InputIterator __last, const allocator_type& __a,
2136               typename enable_if<__is_exactly_cpp17_input_iterator<_InputIterator>::value>::type* = 0);
2137    template <class _ForwardIterator>
2138    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(_ForwardIterator __first, _ForwardIterator __last,
2139               typename enable_if<__is_cpp17_forward_iterator<_ForwardIterator>::value>::type* = 0);
2140    template <class _ForwardIterator>
2141    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(_ForwardIterator __first, _ForwardIterator __last, const allocator_type& __a,
2142               typename enable_if<__is_cpp17_forward_iterator<_ForwardIterator>::value>::type* = 0);
2143
2144    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(const vector& __v);
2145    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(const vector& __v, const allocator_type& __a);
2146    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector& operator=(const vector& __v);
2147
2148#ifndef _LIBCPP_CXX03_LANG
2149    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(initializer_list<value_type> __il);
2150    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(initializer_list<value_type> __il, const allocator_type& __a);
2151
2152    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2153    vector& operator=(initializer_list<value_type> __il)
2154        {assign(__il.begin(), __il.end()); return *this;}
2155
2156#endif // !_LIBCPP_CXX03_LANG
2157
2158    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2159    vector(vector&& __v)
2160#if _LIBCPP_STD_VER > 14
2161        noexcept;
2162#else
2163        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
2164#endif
2165    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector(vector&& __v, const __type_identity_t<allocator_type>& __a);
2166    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2167    vector& operator=(vector&& __v)
2168        _NOEXCEPT_((__noexcept_move_assign_container<_Allocator, __alloc_traits>::value));
2169
2170    template <class _InputIterator>
2171        typename enable_if <__is_exactly_cpp17_input_iterator<_InputIterator>::value,
2172           void
2173        >::type
2174    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 assign(_InputIterator __first, _InputIterator __last);
2175    template <class _ForwardIterator>
2176        typename enable_if
2177        <
2178            __is_cpp17_forward_iterator<_ForwardIterator>::value,
2179           void
2180        >::type
2181    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 assign(_ForwardIterator __first, _ForwardIterator __last);
2182
2183    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void assign(size_type __n, const value_type& __x);
2184
2185#ifndef _LIBCPP_CXX03_LANG
2186    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2187    void assign(initializer_list<value_type> __il)
2188        {assign(__il.begin(), __il.end());}
2189#endif
2190
2191    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 allocator_type get_allocator() const _NOEXCEPT
2192        {return allocator_type(this->__alloc());}
2193
2194    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_type max_size() const _NOEXCEPT;
2195    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2196    size_type capacity() const _NOEXCEPT
2197        {return __internal_cap_to_external(__cap());}
2198    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2199    size_type size() const _NOEXCEPT
2200        {return __size_;}
2201    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2202    bool empty() const _NOEXCEPT
2203        {return __size_ == 0;}
2204    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void reserve(size_type __n);
2205    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void shrink_to_fit() _NOEXCEPT;
2206
2207    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2208    iterator begin() _NOEXCEPT
2209        {return __make_iter(0);}
2210    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2211    const_iterator begin() const _NOEXCEPT
2212        {return __make_iter(0);}
2213    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2214    iterator end() _NOEXCEPT
2215        {return __make_iter(__size_);}
2216    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2217    const_iterator end()   const _NOEXCEPT
2218        {return __make_iter(__size_);}
2219
2220    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2221    reverse_iterator rbegin() _NOEXCEPT
2222        {return       reverse_iterator(end());}
2223    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2224    const_reverse_iterator rbegin() const _NOEXCEPT
2225        {return const_reverse_iterator(end());}
2226    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2227    reverse_iterator rend() _NOEXCEPT
2228        {return       reverse_iterator(begin());}
2229    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2230    const_reverse_iterator rend()   const _NOEXCEPT
2231        {return const_reverse_iterator(begin());}
2232
2233    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2234    const_iterator         cbegin()  const _NOEXCEPT
2235        {return __make_iter(0);}
2236    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2237    const_iterator         cend()    const _NOEXCEPT
2238        {return __make_iter(__size_);}
2239    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2240    const_reverse_iterator crbegin() const _NOEXCEPT
2241        {return rbegin();}
2242    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2243    const_reverse_iterator crend()   const _NOEXCEPT
2244        {return rend();}
2245
2246    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference       operator[](size_type __n)       {return __make_ref(__n);}
2247    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference operator[](size_type __n) const {return __make_ref(__n);}
2248    _LIBCPP_HIDE_FROM_ABI reference       at(size_type __n);
2249    _LIBCPP_HIDE_FROM_ABI const_reference at(size_type __n) const;
2250
2251    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference       front()       {return __make_ref(0);}
2252    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference front() const {return __make_ref(0);}
2253    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference       back()        {return __make_ref(__size_ - 1);}
2254    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_reference back()  const {return __make_ref(__size_ - 1);}
2255
2256    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void push_back(const value_type& __x);
2257#if _LIBCPP_STD_VER > 11
2258    template <class... _Args>
2259#if _LIBCPP_STD_VER > 14
2260    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 reference emplace_back(_Args&&... __args)
2261#else
2262    _LIBCPP_HIDE_FROM_ABI void      emplace_back(_Args&&... __args)
2263#endif
2264    {
2265        push_back ( value_type ( std::forward<_Args>(__args)... ));
2266#if _LIBCPP_STD_VER > 14
2267        return this->back();
2268#endif
2269    }
2270#endif
2271
2272    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void pop_back() {--__size_;}
2273
2274#if _LIBCPP_STD_VER > 11
2275    template <class... _Args>
2276   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator emplace(const_iterator __position, _Args&&... __args)
2277        { return insert ( __position, value_type ( std::forward<_Args>(__args)... )); }
2278#endif
2279
2280    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator insert(const_iterator __position, const value_type& __x);
2281    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator insert(const_iterator __position, size_type __n, const value_type& __x);
2282    template <class _InputIterator>
2283        typename enable_if <__is_exactly_cpp17_input_iterator<_InputIterator>::value,
2284            iterator
2285        >::type
2286        _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 insert(const_iterator __position, _InputIterator __first, _InputIterator __last);
2287    template <class _ForwardIterator>
2288        typename enable_if
2289        <
2290            __is_cpp17_forward_iterator<_ForwardIterator>::value,
2291            iterator
2292        >::type
2293        _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 insert(const_iterator __position, _ForwardIterator __first, _ForwardIterator __last);
2294
2295#ifndef _LIBCPP_CXX03_LANG
2296    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2297    iterator insert(const_iterator __position, initializer_list<value_type> __il)
2298        {return insert(__position, __il.begin(), __il.end());}
2299#endif
2300
2301    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator erase(const_iterator __position);
2302    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator erase(const_iterator __first, const_iterator __last);
2303
2304    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2305    void clear() _NOEXCEPT {__size_ = 0;}
2306
2307    _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(vector&)
2308#if _LIBCPP_STD_VER >= 14
2309        _NOEXCEPT;
2310#else
2311        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
2312                    __is_nothrow_swappable<allocator_type>::value);
2313#endif
2314    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static void swap(reference __x, reference __y) _NOEXCEPT { std::swap(__x, __y); }
2315
2316    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void resize(size_type __sz, value_type __x = false);
2317    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void flip() _NOEXCEPT;
2318
2319    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __invariants() const;
2320
2321private:
2322    _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI
2323    void __throw_length_error() const {
2324        std::__throw_length_error("vector");
2325    }
2326
2327    _LIBCPP_NORETURN _LIBCPP_HIDE_FROM_ABI
2328    void __throw_out_of_range() const {
2329        std::__throw_out_of_range("vector");
2330    }
2331
2332    //  Allocate space for __n objects
2333    //  throws length_error if __n > max_size()
2334    //  throws (probably bad_alloc) if memory run out
2335    //  Precondition:  __begin_ == __end_ == __cap() == 0
2336    //  Precondition:  __n > 0
2337    //  Postcondition:  capacity() >= __n
2338    //  Postcondition:  size() == 0
2339    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __vallocate(size_type __n) {
2340        if (__n > max_size())
2341            __throw_length_error();
2342        auto __allocation = std::__allocate_at_least(__alloc(), __external_cap_to_internal(__n));
2343        __begin_ = __allocation.ptr;
2344        __size_ = 0;
2345        __cap() = __allocation.count;
2346        if (__libcpp_is_constant_evaluated()) {
2347            for (size_type __i = 0; __i != __cap(); ++__i)
2348                std::__construct_at(std::__to_address(__begin_) + __i);
2349        }
2350    }
2351
2352    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __vdeallocate() _NOEXCEPT;
2353    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2354    static size_type __align_it(size_type __new_size) _NOEXCEPT
2355        {return (__new_size + (__bits_per_word-1)) & ~((size_type)__bits_per_word-1);}
2356    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20  size_type __recommend(size_type __new_size) const;
2357    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __construct_at_end(size_type __n, bool __x);
2358    template <class _ForwardIterator>
2359        typename enable_if
2360        <
2361            __is_cpp17_forward_iterator<_ForwardIterator>::value,
2362            void
2363        >::type
2364    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __construct_at_end(_ForwardIterator __first, _ForwardIterator __last);
2365    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __append(size_type __n, const_reference __x);
2366    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2367    reference __make_ref(size_type __pos) _NOEXCEPT
2368        {return reference(__begin_ + __pos / __bits_per_word, __storage_type(1) << __pos % __bits_per_word);}
2369    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2370    const_reference __make_ref(size_type __pos) const _NOEXCEPT {
2371        return __bit_const_reference<vector>(__begin_ + __pos / __bits_per_word,
2372                                             __storage_type(1) << __pos % __bits_per_word);
2373    }
2374    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2375    iterator __make_iter(size_type __pos) _NOEXCEPT
2376        {return iterator(__begin_ + __pos / __bits_per_word, static_cast<unsigned>(__pos % __bits_per_word));}
2377    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2378    const_iterator __make_iter(size_type __pos) const _NOEXCEPT
2379        {return const_iterator(__begin_ + __pos / __bits_per_word, static_cast<unsigned>(__pos % __bits_per_word));}
2380    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2381    iterator __const_iterator_cast(const_iterator __p) _NOEXCEPT
2382        {return begin() + (__p - cbegin());}
2383
2384    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2385    void __copy_assign_alloc(const vector& __v)
2386        {__copy_assign_alloc(__v, integral_constant<bool,
2387                      __storage_traits::propagate_on_container_copy_assignment::value>());}
2388    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2389    void __copy_assign_alloc(const vector& __c, true_type)
2390        {
2391            if (__alloc() != __c.__alloc())
2392                __vdeallocate();
2393            __alloc() = __c.__alloc();
2394        }
2395
2396    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2397    void __copy_assign_alloc(const vector&, false_type)
2398        {}
2399
2400    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign(vector& __c, false_type);
2401    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __move_assign(vector& __c, true_type)
2402        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
2403    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2404    void __move_assign_alloc(vector& __c)
2405        _NOEXCEPT_(
2406            !__storage_traits::propagate_on_container_move_assignment::value ||
2407            is_nothrow_move_assignable<allocator_type>::value)
2408        {__move_assign_alloc(__c, integral_constant<bool,
2409                      __storage_traits::propagate_on_container_move_assignment::value>());}
2410    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2411    void __move_assign_alloc(vector& __c, true_type)
2412        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
2413        {
2414            __alloc() = std::move(__c.__alloc());
2415        }
2416
2417    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2418    void __move_assign_alloc(vector&, false_type)
2419        _NOEXCEPT
2420        {}
2421
2422    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 size_t __hash_code() const _NOEXCEPT;
2423
2424    friend class __bit_reference<vector>;
2425    friend class __bit_const_reference<vector>;
2426    friend class __bit_iterator<vector, false>;
2427    friend class __bit_iterator<vector, true>;
2428    friend struct __bit_array<vector>;
2429    friend struct _LIBCPP_TEMPLATE_VIS hash<vector>;
2430};
2431
2432template <class _Allocator>
2433_LIBCPP_CONSTEXPR_SINCE_CXX20 void
2434vector<bool, _Allocator>::__vdeallocate() _NOEXCEPT
2435{
2436    if (this->__begin_ != nullptr)
2437    {
2438        __storage_traits::deallocate(this->__alloc(), this->__begin_, __cap());
2439        std::__debug_db_invalidate_all(this);
2440        this->__begin_ = nullptr;
2441        this->__size_ = this->__cap() = 0;
2442    }
2443}
2444
2445template <class _Allocator>
2446_LIBCPP_CONSTEXPR_SINCE_CXX20
2447typename vector<bool, _Allocator>::size_type
2448vector<bool, _Allocator>::max_size() const _NOEXCEPT
2449{
2450    size_type __amax = __storage_traits::max_size(__alloc());
2451    size_type __nmax = numeric_limits<size_type>::max() / 2;  // end() >= begin(), always
2452    if (__nmax / __bits_per_word <= __amax)
2453        return __nmax;
2454    return __internal_cap_to_external(__amax);
2455}
2456
2457//  Precondition:  __new_size > capacity()
2458template <class _Allocator>
2459inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2460typename vector<bool, _Allocator>::size_type
2461vector<bool, _Allocator>::__recommend(size_type __new_size) const
2462{
2463    const size_type __ms = max_size();
2464    if (__new_size > __ms)
2465        this->__throw_length_error();
2466    const size_type __cap = capacity();
2467    if (__cap >= __ms / 2)
2468        return __ms;
2469    return std::max(2 * __cap, __align_it(__new_size));
2470}
2471
2472//  Default constructs __n objects starting at __end_
2473//  Precondition:  __n > 0
2474//  Precondition:  size() + __n <= capacity()
2475//  Postcondition:  size() == size() + __n
2476template <class _Allocator>
2477inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2478void
2479vector<bool, _Allocator>::__construct_at_end(size_type __n, bool __x)
2480{
2481    size_type __old_size = this->__size_;
2482    this->__size_ += __n;
2483    if (__old_size == 0 || ((__old_size - 1) / __bits_per_word) != ((this->__size_ - 1) / __bits_per_word))
2484    {
2485        if (this->__size_ <= __bits_per_word)
2486            this->__begin_[0] = __storage_type(0);
2487        else
2488            this->__begin_[(this->__size_ - 1) / __bits_per_word] = __storage_type(0);
2489    }
2490    std::fill_n(__make_iter(__old_size), __n, __x);
2491}
2492
2493template <class _Allocator>
2494template <class _ForwardIterator>
2495_LIBCPP_CONSTEXPR_SINCE_CXX20
2496typename enable_if
2497<
2498    __is_cpp17_forward_iterator<_ForwardIterator>::value,
2499    void
2500>::type
2501vector<bool, _Allocator>::__construct_at_end(_ForwardIterator __first, _ForwardIterator __last)
2502{
2503    size_type __old_size = this->__size_;
2504    this->__size_ += std::distance(__first, __last);
2505    if (__old_size == 0 || ((__old_size - 1) / __bits_per_word) != ((this->__size_ - 1) / __bits_per_word))
2506    {
2507        if (this->__size_ <= __bits_per_word)
2508            this->__begin_[0] = __storage_type(0);
2509        else
2510            this->__begin_[(this->__size_ - 1) / __bits_per_word] = __storage_type(0);
2511    }
2512    std::copy(__first, __last, __make_iter(__old_size));
2513}
2514
2515template <class _Allocator>
2516inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2517vector<bool, _Allocator>::vector()
2518    _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
2519    : __begin_(nullptr),
2520      __size_(0),
2521      __cap_alloc_(0, __default_init_tag())
2522{
2523}
2524
2525template <class _Allocator>
2526inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2527vector<bool, _Allocator>::vector(const allocator_type& __a)
2528#if _LIBCPP_STD_VER <= 14
2529        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
2530#else
2531        _NOEXCEPT
2532#endif
2533    : __begin_(nullptr),
2534      __size_(0),
2535      __cap_alloc_(0, static_cast<__storage_allocator>(__a))
2536{
2537}
2538
2539template <class _Allocator>
2540_LIBCPP_CONSTEXPR_SINCE_CXX20
2541vector<bool, _Allocator>::vector(size_type __n)
2542    : __begin_(nullptr),
2543      __size_(0),
2544      __cap_alloc_(0, __default_init_tag())
2545{
2546    if (__n > 0)
2547    {
2548        __vallocate(__n);
2549        __construct_at_end(__n, false);
2550    }
2551}
2552
2553#if _LIBCPP_STD_VER > 11
2554template <class _Allocator>
2555_LIBCPP_CONSTEXPR_SINCE_CXX20
2556vector<bool, _Allocator>::vector(size_type __n, const allocator_type& __a)
2557    : __begin_(nullptr),
2558      __size_(0),
2559      __cap_alloc_(0, static_cast<__storage_allocator>(__a))
2560{
2561    if (__n > 0)
2562    {
2563        __vallocate(__n);
2564        __construct_at_end(__n, false);
2565    }
2566}
2567#endif
2568
2569template <class _Allocator>
2570_LIBCPP_CONSTEXPR_SINCE_CXX20
2571vector<bool, _Allocator>::vector(size_type __n, const value_type& __x)
2572    : __begin_(nullptr),
2573      __size_(0),
2574      __cap_alloc_(0, __default_init_tag())
2575{
2576    if (__n > 0)
2577    {
2578        __vallocate(__n);
2579        __construct_at_end(__n, __x);
2580    }
2581}
2582
2583template <class _Allocator>
2584_LIBCPP_CONSTEXPR_SINCE_CXX20
2585vector<bool, _Allocator>::vector(size_type __n, const value_type& __x, const allocator_type& __a)
2586    : __begin_(nullptr),
2587      __size_(0),
2588      __cap_alloc_(0, static_cast<__storage_allocator>(__a))
2589{
2590    if (__n > 0)
2591    {
2592        __vallocate(__n);
2593        __construct_at_end(__n, __x);
2594    }
2595}
2596
2597template <class _Allocator>
2598template <class _InputIterator>
2599_LIBCPP_CONSTEXPR_SINCE_CXX20
2600vector<bool, _Allocator>::vector(_InputIterator __first, _InputIterator __last,
2601       typename enable_if<__is_exactly_cpp17_input_iterator<_InputIterator>::value>::type*)
2602    : __begin_(nullptr),
2603      __size_(0),
2604      __cap_alloc_(0, __default_init_tag())
2605{
2606#ifndef _LIBCPP_NO_EXCEPTIONS
2607    try
2608    {
2609#endif // _LIBCPP_NO_EXCEPTIONS
2610        for (; __first != __last; ++__first)
2611            push_back(*__first);
2612#ifndef _LIBCPP_NO_EXCEPTIONS
2613    }
2614    catch (...)
2615    {
2616        if (__begin_ != nullptr)
2617            __storage_traits::deallocate(__alloc(), __begin_, __cap());
2618        std::__debug_db_invalidate_all(this);
2619        throw;
2620    }
2621#endif // _LIBCPP_NO_EXCEPTIONS
2622}
2623
2624template <class _Allocator>
2625template <class _InputIterator>
2626_LIBCPP_CONSTEXPR_SINCE_CXX20
2627vector<bool, _Allocator>::vector(_InputIterator __first, _InputIterator __last, const allocator_type& __a,
2628       typename enable_if<__is_exactly_cpp17_input_iterator<_InputIterator>::value>::type*)
2629    : __begin_(nullptr),
2630      __size_(0),
2631      __cap_alloc_(0, static_cast<__storage_allocator>(__a))
2632{
2633#ifndef _LIBCPP_NO_EXCEPTIONS
2634    try
2635    {
2636#endif // _LIBCPP_NO_EXCEPTIONS
2637        for (; __first != __last; ++__first)
2638            push_back(*__first);
2639#ifndef _LIBCPP_NO_EXCEPTIONS
2640    }
2641    catch (...)
2642    {
2643        if (__begin_ != nullptr)
2644            __storage_traits::deallocate(__alloc(), __begin_, __cap());
2645        std::__debug_db_invalidate_all(this);
2646        throw;
2647    }
2648#endif // _LIBCPP_NO_EXCEPTIONS
2649}
2650
2651template <class _Allocator>
2652template <class _ForwardIterator>
2653_LIBCPP_CONSTEXPR_SINCE_CXX20
2654vector<bool, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last,
2655                                typename enable_if<__is_cpp17_forward_iterator<_ForwardIterator>::value>::type*)
2656    : __begin_(nullptr),
2657      __size_(0),
2658      __cap_alloc_(0, __default_init_tag())
2659{
2660    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
2661    size_type __n = static_cast<size_type>(std::distance(__first, __last));
2662    if (__n > 0)
2663    {
2664        __vallocate(__n);
2665        __construct_at_end(__first, __last);
2666    }
2667    __guard.__complete();
2668}
2669
2670template <class _Allocator>
2671template <class _ForwardIterator>
2672_LIBCPP_CONSTEXPR_SINCE_CXX20
2673vector<bool, _Allocator>::vector(_ForwardIterator __first, _ForwardIterator __last, const allocator_type& __a,
2674                                typename enable_if<__is_cpp17_forward_iterator<_ForwardIterator>::value>::type*)
2675    : __begin_(nullptr),
2676      __size_(0),
2677      __cap_alloc_(0, static_cast<__storage_allocator>(__a))
2678{
2679    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
2680    size_type __n = static_cast<size_type>(std::distance(__first, __last));
2681    if (__n > 0)
2682    {
2683        __vallocate(__n);
2684        __construct_at_end(__first, __last);
2685    }
2686    __guard.__complete();
2687}
2688
2689#ifndef _LIBCPP_CXX03_LANG
2690
2691template <class _Allocator>
2692_LIBCPP_CONSTEXPR_SINCE_CXX20
2693vector<bool, _Allocator>::vector(initializer_list<value_type> __il)
2694    : __begin_(nullptr),
2695      __size_(0),
2696      __cap_alloc_(0, __default_init_tag())
2697{
2698    size_type __n = static_cast<size_type>(__il.size());
2699    if (__n > 0)
2700    {
2701        __vallocate(__n);
2702        __construct_at_end(__il.begin(), __il.end());
2703    }
2704}
2705
2706template <class _Allocator>
2707_LIBCPP_CONSTEXPR_SINCE_CXX20
2708vector<bool, _Allocator>::vector(initializer_list<value_type> __il, const allocator_type& __a)
2709    : __begin_(nullptr),
2710      __size_(0),
2711      __cap_alloc_(0, static_cast<__storage_allocator>(__a))
2712{
2713    size_type __n = static_cast<size_type>(__il.size());
2714    if (__n > 0)
2715    {
2716        __vallocate(__n);
2717        __construct_at_end(__il.begin(), __il.end());
2718    }
2719}
2720
2721#endif // _LIBCPP_CXX03_LANG
2722
2723template <class _Allocator>
2724_LIBCPP_CONSTEXPR_SINCE_CXX20
2725vector<bool, _Allocator>::vector(const vector& __v)
2726    : __begin_(nullptr),
2727      __size_(0),
2728      __cap_alloc_(0, __storage_traits::select_on_container_copy_construction(__v.__alloc()))
2729{
2730    if (__v.size() > 0)
2731    {
2732        __vallocate(__v.size());
2733        __construct_at_end(__v.begin(), __v.end());
2734    }
2735}
2736
2737template <class _Allocator>
2738_LIBCPP_CONSTEXPR_SINCE_CXX20
2739vector<bool, _Allocator>::vector(const vector& __v, const allocator_type& __a)
2740    : __begin_(nullptr),
2741      __size_(0),
2742      __cap_alloc_(0, __a)
2743{
2744    if (__v.size() > 0)
2745    {
2746        __vallocate(__v.size());
2747        __construct_at_end(__v.begin(), __v.end());
2748    }
2749}
2750
2751template <class _Allocator>
2752_LIBCPP_CONSTEXPR_SINCE_CXX20
2753vector<bool, _Allocator>&
2754vector<bool, _Allocator>::operator=(const vector& __v)
2755{
2756    if (this != std::addressof(__v))
2757    {
2758        __copy_assign_alloc(__v);
2759        if (__v.__size_)
2760        {
2761            if (__v.__size_ > capacity())
2762            {
2763                __vdeallocate();
2764                __vallocate(__v.__size_);
2765            }
2766            std::copy(__v.__begin_, __v.__begin_ + __external_cap_to_internal(__v.__size_), __begin_);
2767        }
2768        __size_ = __v.__size_;
2769    }
2770    return *this;
2771}
2772
2773template <class _Allocator>
2774inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 vector<bool, _Allocator>::vector(vector&& __v)
2775#if _LIBCPP_STD_VER > 14
2776    _NOEXCEPT
2777#else
2778    _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
2779#endif
2780    : __begin_(__v.__begin_),
2781      __size_(__v.__size_),
2782      __cap_alloc_(std::move(__v.__cap_alloc_)) {
2783    __v.__begin_ = nullptr;
2784    __v.__size_ = 0;
2785    __v.__cap() = 0;
2786}
2787
2788template <class _Allocator>
2789_LIBCPP_CONSTEXPR_SINCE_CXX20
2790vector<bool, _Allocator>::vector(vector&& __v, const __type_identity_t<allocator_type>& __a)
2791    : __begin_(nullptr),
2792      __size_(0),
2793      __cap_alloc_(0, __a)
2794{
2795    if (__a == allocator_type(__v.__alloc()))
2796    {
2797        this->__begin_ = __v.__begin_;
2798        this->__size_ = __v.__size_;
2799        this->__cap() = __v.__cap();
2800        __v.__begin_ = nullptr;
2801        __v.__cap() = __v.__size_ = 0;
2802    }
2803    else if (__v.size() > 0)
2804    {
2805        __vallocate(__v.size());
2806        __construct_at_end(__v.begin(), __v.end());
2807    }
2808}
2809
2810template <class _Allocator>
2811inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
2812vector<bool, _Allocator>&
2813vector<bool, _Allocator>::operator=(vector&& __v)
2814    _NOEXCEPT_((__noexcept_move_assign_container<_Allocator, __alloc_traits>::value))
2815{
2816    __move_assign(__v, integral_constant<bool,
2817          __storage_traits::propagate_on_container_move_assignment::value>());
2818    return *this;
2819}
2820
2821template <class _Allocator>
2822_LIBCPP_CONSTEXPR_SINCE_CXX20 void
2823vector<bool, _Allocator>::__move_assign(vector& __c, false_type)
2824{
2825    if (__alloc() != __c.__alloc())
2826        assign(__c.begin(), __c.end());
2827    else
2828        __move_assign(__c, true_type());
2829}
2830
2831template <class _Allocator>
2832_LIBCPP_CONSTEXPR_SINCE_CXX20 void
2833vector<bool, _Allocator>::__move_assign(vector& __c, true_type)
2834    _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
2835{
2836    __vdeallocate();
2837    __move_assign_alloc(__c);
2838    this->__begin_ = __c.__begin_;
2839    this->__size_ = __c.__size_;
2840    this->__cap() = __c.__cap();
2841    __c.__begin_ = nullptr;
2842    __c.__cap() = __c.__size_ = 0;
2843}
2844
2845template <class _Allocator>
2846_LIBCPP_CONSTEXPR_SINCE_CXX20 void
2847vector<bool, _Allocator>::assign(size_type __n, const value_type& __x)
2848{
2849    __size_ = 0;
2850    if (__n > 0)
2851    {
2852        size_type __c = capacity();
2853        if (__n <= __c)
2854            __size_ = __n;
2855        else
2856        {
2857            vector __v(get_allocator());
2858            __v.reserve(__recommend(__n));
2859            __v.__size_ = __n;
2860            swap(__v);
2861        }
2862        std::fill_n(begin(), __n, __x);
2863    }
2864    std::__debug_db_invalidate_all(this);
2865}
2866
2867template <class _Allocator>
2868template <class _InputIterator>
2869_LIBCPP_CONSTEXPR_SINCE_CXX20 typename enable_if <__is_exactly_cpp17_input_iterator<_InputIterator>::value,
2870   void
2871>::type
2872vector<bool, _Allocator>::assign(_InputIterator __first, _InputIterator __last)
2873{
2874    clear();
2875    for (; __first != __last; ++__first)
2876        push_back(*__first);
2877}
2878
2879template <class _Allocator>
2880template <class _ForwardIterator>
2881_LIBCPP_CONSTEXPR_SINCE_CXX20
2882typename enable_if
2883<
2884    __is_cpp17_forward_iterator<_ForwardIterator>::value,
2885   void
2886>::type
2887vector<bool, _Allocator>::assign(_ForwardIterator __first, _ForwardIterator __last)
2888{
2889    clear();
2890    difference_type __ns = std::distance(__first, __last);
2891    _LIBCPP_ASSERT(__ns >= 0, "invalid range specified");
2892    const size_t __n = static_cast<size_type>(__ns);
2893    if (__n)
2894    {
2895        if (__n > capacity())
2896        {
2897            __vdeallocate();
2898            __vallocate(__n);
2899        }
2900        __construct_at_end(__first, __last);
2901    }
2902}
2903
2904template <class _Allocator>
2905_LIBCPP_CONSTEXPR_SINCE_CXX20 void
2906vector<bool, _Allocator>::reserve(size_type __n)
2907{
2908    if (__n > capacity())
2909    {
2910        if (__n > max_size())
2911            this->__throw_length_error();
2912        vector __v(this->get_allocator());
2913        __v.__vallocate(__n);
2914        __v.__construct_at_end(this->begin(), this->end());
2915        swap(__v);
2916        std::__debug_db_invalidate_all(this);
2917    }
2918}
2919
2920template <class _Allocator>
2921_LIBCPP_CONSTEXPR_SINCE_CXX20 void
2922vector<bool, _Allocator>::shrink_to_fit() _NOEXCEPT
2923{
2924    if (__external_cap_to_internal(size()) > __cap())
2925    {
2926#ifndef _LIBCPP_NO_EXCEPTIONS
2927        try
2928        {
2929#endif // _LIBCPP_NO_EXCEPTIONS
2930            vector(*this, allocator_type(__alloc())).swap(*this);
2931#ifndef _LIBCPP_NO_EXCEPTIONS
2932        }
2933        catch (...)
2934        {
2935        }
2936#endif // _LIBCPP_NO_EXCEPTIONS
2937    }
2938}
2939
2940template <class _Allocator>
2941typename vector<bool, _Allocator>::reference
2942vector<bool, _Allocator>::at(size_type __n)
2943{
2944    if (__n >= size())
2945        this->__throw_out_of_range();
2946    return (*this)[__n];
2947}
2948
2949template <class _Allocator>
2950typename vector<bool, _Allocator>::const_reference
2951vector<bool, _Allocator>::at(size_type __n) const
2952{
2953    if (__n >= size())
2954        this->__throw_out_of_range();
2955    return (*this)[__n];
2956}
2957
2958template <class _Allocator>
2959_LIBCPP_CONSTEXPR_SINCE_CXX20 void
2960vector<bool, _Allocator>::push_back(const value_type& __x)
2961{
2962    if (this->__size_ == this->capacity())
2963        reserve(__recommend(this->__size_ + 1));
2964    ++this->__size_;
2965    back() = __x;
2966}
2967
2968template <class _Allocator>
2969_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::iterator
2970vector<bool, _Allocator>::insert(const_iterator __position, const value_type& __x)
2971{
2972    iterator __r;
2973    if (size() < capacity())
2974    {
2975        const_iterator __old_end = end();
2976        ++__size_;
2977        std::copy_backward(__position, __old_end, end());
2978        __r = __const_iterator_cast(__position);
2979    }
2980    else
2981    {
2982        vector __v(get_allocator());
2983        __v.reserve(__recommend(__size_ + 1));
2984        __v.__size_ = __size_ + 1;
2985        __r = std::copy(cbegin(), __position, __v.begin());
2986        std::copy_backward(__position, cend(), __v.end());
2987        swap(__v);
2988    }
2989    *__r = __x;
2990    return __r;
2991}
2992
2993template <class _Allocator>
2994_LIBCPP_CONSTEXPR_SINCE_CXX20 typename vector<bool, _Allocator>::iterator
2995vector<bool, _Allocator>::insert(const_iterator __position, size_type __n, const value_type& __x)
2996{
2997    iterator __r;
2998    size_type __c = capacity();
2999    if (__n <= __c && size() <= __c - __n)
3000    {
3001        const_iterator __old_end = end();
3002        __size_ += __n;
3003        std::copy_backward(__position, __old_end, end());
3004        __r = __const_iterator_cast(__position);
3005    }
3006    else
3007    {
3008        vector __v(get_allocator());
3009        __v.reserve(__recommend(__size_ + __n));
3010        __v.__size_ = __size_ + __n;
3011        __r = std::copy(cbegin(), __position, __v.begin());
3012        std::copy_backward(__position, cend(), __v.end());
3013        swap(__v);
3014    }
3015    std::fill_n(__r, __n, __x);
3016    return __r;
3017}
3018
3019template <class _Allocator>
3020template <class _InputIterator>
3021_LIBCPP_CONSTEXPR_SINCE_CXX20 typename enable_if <__is_exactly_cpp17_input_iterator<_InputIterator>::value,
3022    typename vector<bool, _Allocator>::iterator
3023>::type
3024vector<bool, _Allocator>::insert(const_iterator __position, _InputIterator __first, _InputIterator __last)
3025{
3026    difference_type __off = __position - begin();
3027    iterator __p = __const_iterator_cast(__position);
3028    iterator __old_end = end();
3029    for (; size() != capacity() && __first != __last; ++__first)
3030    {
3031        ++this->__size_;
3032        back() = *__first;
3033    }
3034    vector __v(get_allocator());
3035    if (__first != __last)
3036    {
3037#ifndef _LIBCPP_NO_EXCEPTIONS
3038        try
3039        {
3040#endif // _LIBCPP_NO_EXCEPTIONS
3041            __v.assign(__first, __last);
3042            difference_type __old_size = static_cast<difference_type>(__old_end - begin());
3043            difference_type __old_p = __p - begin();
3044            reserve(__recommend(size() + __v.size()));
3045            __p = begin() + __old_p;
3046            __old_end = begin() + __old_size;
3047#ifndef _LIBCPP_NO_EXCEPTIONS
3048        }
3049        catch (...)
3050        {
3051            erase(__old_end, end());
3052            throw;
3053        }
3054#endif // _LIBCPP_NO_EXCEPTIONS
3055    }
3056    __p = std::rotate(__p, __old_end, end());
3057    insert(__p, __v.begin(), __v.end());
3058    return begin() + __off;
3059}
3060
3061template <class _Allocator>
3062template <class _ForwardIterator>
3063_LIBCPP_CONSTEXPR_SINCE_CXX20
3064typename enable_if
3065<
3066    __is_cpp17_forward_iterator<_ForwardIterator>::value,
3067    typename vector<bool, _Allocator>::iterator
3068>::type
3069vector<bool, _Allocator>::insert(const_iterator __position, _ForwardIterator __first, _ForwardIterator __last)
3070{
3071    const difference_type __n_signed = std::distance(__first, __last);
3072    _LIBCPP_ASSERT(__n_signed >= 0, "invalid range specified");
3073    const size_type __n = static_cast<size_type>(__n_signed);
3074    iterator __r;
3075    size_type __c = capacity();
3076    if (__n <= __c && size() <= __c - __n)
3077    {
3078        const_iterator __old_end = end();
3079        __size_ += __n;
3080        std::copy_backward(__position, __old_end, end());
3081        __r = __const_iterator_cast(__position);
3082    }
3083    else
3084    {
3085        vector __v(get_allocator());
3086        __v.reserve(__recommend(__size_ + __n));
3087        __v.__size_ = __size_ + __n;
3088        __r = std::copy(cbegin(), __position, __v.begin());
3089        std::copy_backward(__position, cend(), __v.end());
3090        swap(__v);
3091    }
3092    std::copy(__first, __last, __r);
3093    return __r;
3094}
3095
3096template <class _Allocator>
3097inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
3098typename vector<bool, _Allocator>::iterator
3099vector<bool, _Allocator>::erase(const_iterator __position)
3100{
3101    iterator __r = __const_iterator_cast(__position);
3102    std::copy(__position + 1, this->cend(), __r);
3103    --__size_;
3104    return __r;
3105}
3106
3107template <class _Allocator>
3108_LIBCPP_CONSTEXPR_SINCE_CXX20
3109typename vector<bool, _Allocator>::iterator
3110vector<bool, _Allocator>::erase(const_iterator __first, const_iterator __last)
3111{
3112    iterator __r = __const_iterator_cast(__first);
3113    difference_type __d = __last - __first;
3114    std::copy(__last, this->cend(), __r);
3115    __size_ -= __d;
3116    return __r;
3117}
3118
3119template <class _Allocator>
3120_LIBCPP_CONSTEXPR_SINCE_CXX20 void
3121vector<bool, _Allocator>::swap(vector& __x)
3122#if _LIBCPP_STD_VER >= 14
3123    _NOEXCEPT
3124#else
3125    _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
3126                __is_nothrow_swappable<allocator_type>::value)
3127#endif
3128{
3129    std::swap(this->__begin_, __x.__begin_);
3130    std::swap(this->__size_, __x.__size_);
3131    std::swap(this->__cap(), __x.__cap());
3132    std::__swap_allocator(this->__alloc(), __x.__alloc(),
3133        integral_constant<bool, __alloc_traits::propagate_on_container_swap::value>());
3134}
3135
3136template <class _Allocator>
3137_LIBCPP_CONSTEXPR_SINCE_CXX20 void
3138vector<bool, _Allocator>::resize(size_type __sz, value_type __x)
3139{
3140    size_type __cs = size();
3141    if (__cs < __sz)
3142    {
3143        iterator __r;
3144        size_type __c = capacity();
3145        size_type __n = __sz - __cs;
3146        if (__n <= __c && __cs <= __c - __n)
3147        {
3148            __r = end();
3149            __size_ += __n;
3150        }
3151        else
3152        {
3153            vector __v(get_allocator());
3154            __v.reserve(__recommend(__size_ + __n));
3155            __v.__size_ = __size_ + __n;
3156            __r = std::copy(cbegin(), cend(), __v.begin());
3157            swap(__v);
3158        }
3159        std::fill_n(__r, __n, __x);
3160    }
3161    else
3162        __size_ = __sz;
3163}
3164
3165template <class _Allocator>
3166_LIBCPP_CONSTEXPR_SINCE_CXX20 void
3167vector<bool, _Allocator>::flip() _NOEXCEPT
3168{
3169    // do middle whole words
3170    size_type __n = __size_;
3171    __storage_pointer __p = __begin_;
3172    for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)
3173        *__p = ~*__p;
3174    // do last partial word
3175    if (__n > 0)
3176    {
3177        __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
3178        __storage_type __b = *__p & __m;
3179        *__p &= ~__m;
3180        *__p |= ~__b & __m;
3181    }
3182}
3183
3184template <class _Allocator>
3185_LIBCPP_CONSTEXPR_SINCE_CXX20 bool
3186vector<bool, _Allocator>::__invariants() const
3187{
3188    if (this->__begin_ == nullptr)
3189    {
3190        if (this->__size_ != 0 || this->__cap() != 0)
3191            return false;
3192    }
3193    else
3194    {
3195        if (this->__cap() == 0)
3196            return false;
3197        if (this->__size_ > this->capacity())
3198            return false;
3199    }
3200    return true;
3201}
3202
3203template <class _Allocator>
3204_LIBCPP_CONSTEXPR_SINCE_CXX20 size_t
3205vector<bool, _Allocator>::__hash_code() const _NOEXCEPT
3206{
3207    size_t __h = 0;
3208    // do middle whole words
3209    size_type __n = __size_;
3210    __storage_pointer __p = __begin_;
3211    for (; __n >= __bits_per_word; ++__p, __n -= __bits_per_word)
3212        __h ^= *__p;
3213    // do last partial word
3214    if (__n > 0)
3215    {
3216        const __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
3217        __h ^= *__p & __m;
3218    }
3219    return __h;
3220}
3221
3222template <class _Allocator>
3223struct _LIBCPP_TEMPLATE_VIS hash<vector<bool, _Allocator> >
3224    : public __unary_function<vector<bool, _Allocator>, size_t>
3225{
3226    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
3227    size_t operator()(const vector<bool, _Allocator>& __vec) const _NOEXCEPT
3228        {return __vec.__hash_code();}
3229};
3230
3231template <class _Tp, class _Allocator>
3232_LIBCPP_CONSTEXPR_SINCE_CXX20
3233inline _LIBCPP_HIDE_FROM_ABI
3234bool
3235operator==(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y)
3236{
3237    const typename vector<_Tp, _Allocator>::size_type __sz = __x.size();
3238    return __sz == __y.size() && std::equal(__x.begin(), __x.end(), __y.begin());
3239}
3240
3241template <class _Tp, class _Allocator>
3242_LIBCPP_CONSTEXPR_SINCE_CXX20
3243inline _LIBCPP_HIDE_FROM_ABI
3244bool
3245operator!=(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y)
3246{
3247    return !(__x == __y);
3248}
3249
3250template <class _Tp, class _Allocator>
3251_LIBCPP_CONSTEXPR_SINCE_CXX20
3252inline _LIBCPP_HIDE_FROM_ABI
3253bool
3254operator< (const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y)
3255{
3256    return std::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
3257}
3258
3259template <class _Tp, class _Allocator>
3260_LIBCPP_CONSTEXPR_SINCE_CXX20
3261inline _LIBCPP_HIDE_FROM_ABI
3262bool
3263operator> (const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y)
3264{
3265    return __y < __x;
3266}
3267
3268template <class _Tp, class _Allocator>
3269_LIBCPP_CONSTEXPR_SINCE_CXX20
3270inline _LIBCPP_HIDE_FROM_ABI
3271bool
3272operator>=(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y)
3273{
3274    return !(__x < __y);
3275}
3276
3277template <class _Tp, class _Allocator>
3278_LIBCPP_CONSTEXPR_SINCE_CXX20
3279inline _LIBCPP_HIDE_FROM_ABI
3280bool
3281operator<=(const vector<_Tp, _Allocator>& __x, const vector<_Tp, _Allocator>& __y)
3282{
3283    return !(__y < __x);
3284}
3285
3286template <class _Tp, class _Allocator>
3287_LIBCPP_CONSTEXPR_SINCE_CXX20
3288inline _LIBCPP_HIDE_FROM_ABI
3289void
3290swap(vector<_Tp, _Allocator>& __x, vector<_Tp, _Allocator>& __y)
3291    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
3292{
3293    __x.swap(__y);
3294}
3295
3296#if _LIBCPP_STD_VER > 17
3297template <class _Tp, class _Allocator, class _Up>
3298_LIBCPP_CONSTEXPR_SINCE_CXX20
3299inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::size_type
3300erase(vector<_Tp, _Allocator>& __c, const _Up& __v) {
3301  auto __old_size = __c.size();
3302  __c.erase(std::remove(__c.begin(), __c.end(), __v), __c.end());
3303  return __old_size - __c.size();
3304}
3305
3306template <class _Tp, class _Allocator, class _Predicate>
3307_LIBCPP_CONSTEXPR_SINCE_CXX20
3308inline _LIBCPP_HIDE_FROM_ABI typename vector<_Tp, _Allocator>::size_type
3309erase_if(vector<_Tp, _Allocator>& __c, _Predicate __pred) {
3310  auto __old_size = __c.size();
3311  __c.erase(std::remove_if(__c.begin(), __c.end(), __pred), __c.end());
3312  return __old_size - __c.size();
3313}
3314
3315template <>
3316inline constexpr bool __format::__enable_insertable<vector<char>> = true;
3317#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
3318template <>
3319inline constexpr bool __format::__enable_insertable<vector<wchar_t>> = true;
3320#endif
3321
3322#endif // _LIBCPP_STD_VER > 17
3323
3324#if _LIBCPP_STD_VER > 20
3325template <class _Tp, class CharT>
3326// Since is-vector-bool-reference is only used once it's inlined here.
3327  requires same_as<typename _Tp::__container, vector<bool, typename _Tp::__container::allocator_type>>
3328struct _LIBCPP_TEMPLATE_VIS _LIBCPP_AVAILABILITY_FORMAT formatter<_Tp, CharT> {
3329private:
3330  formatter<bool, CharT> __underlying_;
3331
3332public:
3333  template <class _ParseContext>
3334  _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
3335        return __underlying_.parse(__ctx);
3336  }
3337
3338  template <class _FormatContext>
3339  _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(const _Tp& __ref, _FormatContext& __ctx) const {
3340        return __underlying_.format(__ref, __ctx);
3341  }
3342};
3343#endif // _LIBCPP_STD_VER > 20
3344
3345_LIBCPP_END_NAMESPACE_STD
3346
3347#if _LIBCPP_STD_VER > 14
3348_LIBCPP_BEGIN_NAMESPACE_STD
3349namespace pmr {
3350template <class _ValueT>
3351using vector = std::vector<_ValueT, polymorphic_allocator<_ValueT>>;
3352} // namespace pmr
3353_LIBCPP_END_NAMESPACE_STD
3354#endif
3355
3356_LIBCPP_POP_MACROS
3357
3358#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
3359#  include <algorithm>
3360#  include <atomic>
3361#  include <concepts>
3362#  include <typeinfo>
3363#  include <utility>
3364#endif
3365
3366#endif // _LIBCPP_VECTOR
3367