xref: /llvm-project-15.0.7/libcxx/include/deque (revision d5658b08)
1// -*- C++ -*-
2//===---------------------------- deque -----------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_DEQUE
12#define _LIBCPP_DEQUE
13
14/*
15    deque synopsis
16
17namespace std
18{
19
20template <class T, class Allocator = allocator<T> >
21class deque
22{
23public:
24    // types:
25    typedef T value_type;
26    typedef Allocator allocator_type;
27
28    typedef typename allocator_type::reference       reference;
29    typedef typename allocator_type::const_reference const_reference;
30    typedef implementation-defined                   iterator;
31    typedef implementation-defined                   const_iterator;
32    typedef typename allocator_type::size_type       size_type;
33    typedef typename allocator_type::difference_type difference_type;
34
35    typedef typename allocator_type::pointer         pointer;
36    typedef typename allocator_type::const_pointer   const_pointer;
37    typedef std::reverse_iterator<iterator>          reverse_iterator;
38    typedef std::reverse_iterator<const_iterator>    const_reverse_iterator;
39
40    // construct/copy/destroy:
41    deque() noexcept(is_nothrow_default_constructible<allocator_type>::value);
42    explicit deque(const allocator_type& a);
43    explicit deque(size_type n);
44    explicit deque(size_type n, const allocator_type& a); // C++14
45    deque(size_type n, const value_type& v);
46    deque(size_type n, const value_type& v, const allocator_type& a);
47    template <class InputIterator>
48        deque(InputIterator f, InputIterator l);
49    template <class InputIterator>
50        deque(InputIterator f, InputIterator l, const allocator_type& a);
51    deque(const deque& c);
52    deque(deque&& c)
53        noexcept(is_nothrow_move_constructible<allocator_type>::value);
54    deque(initializer_list<value_type> il, const Allocator& a = allocator_type());
55    deque(const deque& c, const allocator_type& a);
56    deque(deque&& c, const allocator_type& a);
57    ~deque();
58
59    deque& operator=(const deque& c);
60    deque& operator=(deque&& c)
61        noexcept(
62             allocator_type::propagate_on_container_move_assignment::value &&
63             is_nothrow_move_assignable<allocator_type>::value);
64    deque& operator=(initializer_list<value_type> il);
65
66    template <class InputIterator>
67        void assign(InputIterator f, InputIterator l);
68    void assign(size_type n, const value_type& v);
69    void assign(initializer_list<value_type> il);
70
71    allocator_type get_allocator() const noexcept;
72
73    // iterators:
74
75    iterator       begin() noexcept;
76    const_iterator begin() const noexcept;
77    iterator       end() noexcept;
78    const_iterator end() const noexcept;
79
80    reverse_iterator       rbegin() noexcept;
81    const_reverse_iterator rbegin() const noexcept;
82    reverse_iterator       rend() noexcept;
83    const_reverse_iterator rend() const noexcept;
84
85    const_iterator         cbegin() const noexcept;
86    const_iterator         cend() const noexcept;
87    const_reverse_iterator crbegin() const noexcept;
88    const_reverse_iterator crend() const noexcept;
89
90    // capacity:
91    size_type size() const noexcept;
92    size_type max_size() const noexcept;
93    void resize(size_type n);
94    void resize(size_type n, const value_type& v);
95    void shrink_to_fit();
96    bool empty() const noexcept;
97
98    // element access:
99    reference operator[](size_type i);
100    const_reference operator[](size_type i) const;
101    reference at(size_type i);
102    const_reference at(size_type i) const;
103    reference front();
104    const_reference front() const;
105    reference back();
106    const_reference back() const;
107
108    // modifiers:
109    void push_front(const value_type& v);
110    void push_front(value_type&& v);
111    void push_back(const value_type& v);
112    void push_back(value_type&& v);
113    template <class... Args> void emplace_front(Args&&... args);
114    template <class... Args> void emplace_back(Args&&... args);
115    template <class... Args> iterator emplace(const_iterator p, Args&&... args);
116    iterator insert(const_iterator p, const value_type& v);
117    iterator insert(const_iterator p, value_type&& v);
118    iterator insert(const_iterator p, size_type n, const value_type& v);
119    template <class InputIterator>
120        iterator insert(const_iterator p, InputIterator f, InputIterator l);
121    iterator insert(const_iterator p, initializer_list<value_type> il);
122    void pop_front();
123    void pop_back();
124    iterator erase(const_iterator p);
125    iterator erase(const_iterator f, const_iterator l);
126    void swap(deque& c)
127        noexcept(allocator_traits<allocator_type>::is_always_equal::value);  // C++17
128    void clear() noexcept;
129};
130
131template <class T, class Allocator>
132    bool operator==(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
133template <class T, class Allocator>
134    bool operator< (const deque<T,Allocator>& x, const deque<T,Allocator>& y);
135template <class T, class Allocator>
136    bool operator!=(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
137template <class T, class Allocator>
138    bool operator> (const deque<T,Allocator>& x, const deque<T,Allocator>& y);
139template <class T, class Allocator>
140    bool operator>=(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
141template <class T, class Allocator>
142    bool operator<=(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
143
144// specialized algorithms:
145template <class T, class Allocator>
146    void swap(deque<T,Allocator>& x, deque<T,Allocator>& y)
147         noexcept(noexcept(x.swap(y)));
148
149}  // std
150
151*/
152
153#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
154#pragma GCC system_header
155#endif
156
157#include <__config>
158#include <__split_buffer>
159#include <type_traits>
160#include <initializer_list>
161#include <iterator>
162#include <algorithm>
163#include <stdexcept>
164
165#include <__undef_min_max>
166
167_LIBCPP_BEGIN_NAMESPACE_STD
168
169template <class _Tp, class _Allocator> class __deque_base;
170template <class _Tp, class _Allocator = allocator<_Tp> > class _LIBCPP_TYPE_VIS_ONLY deque;
171
172template <class _ValueType, class _Pointer, class _Reference, class _MapPointer,
173          class _DiffType, _DiffType _BlockSize>
174class _LIBCPP_TYPE_VIS_ONLY __deque_iterator;
175
176template <class _RAIter,
177          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
178__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
179copy(_RAIter __f,
180     _RAIter __l,
181     __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
182     typename enable_if<__is_random_access_iterator<_RAIter>::value>::type* = 0);
183
184template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
185          class _OutputIterator>
186_OutputIterator
187copy(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
188     __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
189     _OutputIterator __r);
190
191template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
192          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
193__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
194copy(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
195     __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
196     __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r);
197
198template <class _RAIter,
199          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
200__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
201copy_backward(_RAIter __f,
202              _RAIter __l,
203              __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
204              typename enable_if<__is_random_access_iterator<_RAIter>::value>::type* = 0);
205
206template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
207          class _OutputIterator>
208_OutputIterator
209copy_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
210              __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
211              _OutputIterator __r);
212
213template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
214          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
215__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
216copy_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
217              __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
218              __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r);
219
220template <class _RAIter,
221          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
222__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
223move(_RAIter __f,
224     _RAIter __l,
225     __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
226     typename enable_if<__is_random_access_iterator<_RAIter>::value>::type* = 0);
227
228template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
229          class _OutputIterator>
230_OutputIterator
231move(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
232     __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
233     _OutputIterator __r);
234
235template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
236          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
237__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
238move(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
239     __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
240     __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r);
241
242template <class _RAIter,
243          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
244__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
245move_backward(_RAIter __f,
246              _RAIter __l,
247              __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
248              typename enable_if<__is_random_access_iterator<_RAIter>::value>::type* = 0);
249
250template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
251          class _OutputIterator>
252_OutputIterator
253move_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
254              __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
255              _OutputIterator __r);
256
257template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
258          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
259__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
260move_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
261              __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
262              __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r);
263
264template <class _ValueType, class _DiffType>
265struct __deque_block_size {
266  static const _DiffType value = sizeof(_ValueType) < 256 ? 4096 / sizeof(_ValueType) : 16;
267};
268
269template <class _ValueType, class _Pointer, class _Reference, class _MapPointer,
270          class _DiffType, _DiffType _BS =
271#ifdef _LIBCPP_ABI_INCOMPLETE_TYPES_IN_DEQUE
272// Keep template parameter to avoid changing all template declarations thoughout
273// this file.
274                               0
275#else
276                               __deque_block_size<_ValueType, _DiffType>::value
277#endif
278          >
279class _LIBCPP_TYPE_VIS_ONLY __deque_iterator
280{
281    typedef _MapPointer __map_iterator;
282public:
283    typedef _Pointer  pointer;
284    typedef _DiffType difference_type;
285private:
286    __map_iterator __m_iter_;
287    pointer        __ptr_;
288
289    static const difference_type __block_size;
290public:
291    typedef _ValueType                  value_type;
292    typedef random_access_iterator_tag  iterator_category;
293    typedef _Reference                  reference;
294
295    _LIBCPP_INLINE_VISIBILITY __deque_iterator() _NOEXCEPT
296#if _LIBCPP_STD_VER > 11
297     : __m_iter_(nullptr), __ptr_(nullptr)
298#endif
299     {}
300
301    template <class _Pp, class _Rp, class _MP>
302    _LIBCPP_INLINE_VISIBILITY
303    __deque_iterator(const __deque_iterator<value_type, _Pp, _Rp, _MP, difference_type, _BS>& __it,
304                typename enable_if<is_convertible<_Pp, pointer>::value>::type* = 0) _NOEXCEPT
305        : __m_iter_(__it.__m_iter_), __ptr_(__it.__ptr_) {}
306
307    _LIBCPP_INLINE_VISIBILITY reference operator*() const {return *__ptr_;}
308    _LIBCPP_INLINE_VISIBILITY pointer operator->() const {return __ptr_;}
309
310    _LIBCPP_INLINE_VISIBILITY __deque_iterator& operator++()
311    {
312        if (++__ptr_ - *__m_iter_ == __block_size)
313        {
314            ++__m_iter_;
315            __ptr_ = *__m_iter_;
316        }
317        return *this;
318    }
319
320    _LIBCPP_INLINE_VISIBILITY __deque_iterator operator++(int)
321    {
322        __deque_iterator __tmp = *this;
323        ++(*this);
324        return __tmp;
325    }
326
327    _LIBCPP_INLINE_VISIBILITY __deque_iterator& operator--()
328    {
329        if (__ptr_ == *__m_iter_)
330        {
331            --__m_iter_;
332            __ptr_ = *__m_iter_ + __block_size;
333        }
334        --__ptr_;
335        return *this;
336    }
337
338    _LIBCPP_INLINE_VISIBILITY __deque_iterator operator--(int)
339    {
340        __deque_iterator __tmp = *this;
341        --(*this);
342        return __tmp;
343    }
344
345    _LIBCPP_INLINE_VISIBILITY __deque_iterator& operator+=(difference_type __n)
346    {
347        if (__n != 0)
348        {
349            __n += __ptr_ - *__m_iter_;
350            if (__n > 0)
351            {
352                __m_iter_ += __n / __block_size;
353                __ptr_ = *__m_iter_ + __n % __block_size;
354            }
355            else // (__n < 0)
356            {
357                difference_type __z = __block_size - 1 - __n;
358                __m_iter_ -= __z / __block_size;
359                __ptr_ = *__m_iter_ + (__block_size - 1 - __z % __block_size);
360            }
361        }
362        return *this;
363    }
364
365    _LIBCPP_INLINE_VISIBILITY __deque_iterator& operator-=(difference_type __n)
366    {
367        return *this += -__n;
368    }
369
370    _LIBCPP_INLINE_VISIBILITY __deque_iterator operator+(difference_type __n) const
371    {
372        __deque_iterator __t(*this);
373        __t += __n;
374        return __t;
375    }
376
377    _LIBCPP_INLINE_VISIBILITY __deque_iterator operator-(difference_type __n) const
378    {
379        __deque_iterator __t(*this);
380        __t -= __n;
381        return __t;
382    }
383
384    _LIBCPP_INLINE_VISIBILITY
385    friend __deque_iterator operator+(difference_type __n, const __deque_iterator& __it)
386        {return __it + __n;}
387
388    _LIBCPP_INLINE_VISIBILITY
389    friend difference_type operator-(const __deque_iterator& __x, const __deque_iterator& __y)
390    {
391        if (__x != __y)
392            return (__x.__m_iter_ - __y.__m_iter_) * __block_size
393                 + (__x.__ptr_ - *__x.__m_iter_)
394                 - (__y.__ptr_ - *__y.__m_iter_);
395        return 0;
396    }
397
398    _LIBCPP_INLINE_VISIBILITY reference operator[](difference_type __n) const
399        {return *(*this + __n);}
400
401    _LIBCPP_INLINE_VISIBILITY friend
402        bool operator==(const __deque_iterator& __x, const __deque_iterator& __y)
403        {return __x.__ptr_ == __y.__ptr_;}
404
405    _LIBCPP_INLINE_VISIBILITY friend
406        bool operator!=(const __deque_iterator& __x, const __deque_iterator& __y)
407        {return !(__x == __y);}
408
409    _LIBCPP_INLINE_VISIBILITY friend
410        bool operator<(const __deque_iterator& __x, const __deque_iterator& __y)
411        {return __x.__m_iter_ < __y.__m_iter_ ||
412               (__x.__m_iter_ == __y.__m_iter_ && __x.__ptr_ < __y.__ptr_);}
413
414    _LIBCPP_INLINE_VISIBILITY friend
415        bool operator>(const __deque_iterator& __x, const __deque_iterator& __y)
416        {return __y < __x;}
417
418    _LIBCPP_INLINE_VISIBILITY friend
419        bool operator<=(const __deque_iterator& __x, const __deque_iterator& __y)
420        {return !(__y < __x);}
421
422    _LIBCPP_INLINE_VISIBILITY friend
423        bool operator>=(const __deque_iterator& __x, const __deque_iterator& __y)
424        {return !(__x < __y);}
425
426private:
427    _LIBCPP_INLINE_VISIBILITY __deque_iterator(__map_iterator __m, pointer __p) _NOEXCEPT
428        : __m_iter_(__m), __ptr_(__p) {}
429
430    template <class _Tp, class _Ap> friend class __deque_base;
431    template <class _Tp, class _Ap> friend class _LIBCPP_TYPE_VIS_ONLY deque;
432    template <class _Vp, class _Pp, class _Rp, class _MP, class _Dp, _Dp>
433        friend class _LIBCPP_TYPE_VIS_ONLY __deque_iterator;
434
435    template <class _RAIter,
436              class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
437    friend
438    __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
439    copy(_RAIter __f,
440         _RAIter __l,
441         __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
442         typename enable_if<__is_random_access_iterator<_RAIter>::value>::type*);
443
444    template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
445              class _OutputIterator>
446    friend
447    _OutputIterator
448    copy(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
449         __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
450         _OutputIterator __r);
451
452    template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
453              class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
454    friend
455    __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
456    copy(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
457         __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
458         __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r);
459
460    template <class _RAIter,
461              class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
462    friend
463    __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
464    copy_backward(_RAIter __f,
465                  _RAIter __l,
466                  __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
467                  typename enable_if<__is_random_access_iterator<_RAIter>::value>::type*);
468
469    template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
470              class _OutputIterator>
471    friend
472    _OutputIterator
473    copy_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
474                  __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
475                  _OutputIterator __r);
476
477    template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
478              class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
479    friend
480    __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
481    copy_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
482                  __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
483                  __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r);
484
485    template <class _RAIter,
486              class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
487    friend
488    __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
489    move(_RAIter __f,
490         _RAIter __l,
491         __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
492         typename enable_if<__is_random_access_iterator<_RAIter>::value>::type*);
493
494    template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
495              class _OutputIterator>
496    friend
497    _OutputIterator
498    move(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
499         __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
500         _OutputIterator __r);
501
502    template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
503              class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
504    friend
505    __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
506    move(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
507         __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
508         __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r);
509
510    template <class _RAIter,
511              class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
512    friend
513    __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
514    move_backward(_RAIter __f,
515                  _RAIter __l,
516                  __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
517                  typename enable_if<__is_random_access_iterator<_RAIter>::value>::type*);
518
519    template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
520              class _OutputIterator>
521    friend
522    _OutputIterator
523    move_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
524                  __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
525                  _OutputIterator __r);
526
527    template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
528              class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
529    friend
530    __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
531    move_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
532                  __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
533                  __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r);
534};
535
536template <class _ValueType, class _Pointer, class _Reference, class _MapPointer,
537          class _DiffType, _DiffType _BlockSize>
538const _DiffType __deque_iterator<_ValueType, _Pointer, _Reference, _MapPointer,
539                                 _DiffType, _BlockSize>::__block_size =
540    __deque_block_size<_ValueType, _DiffType>::value;
541
542// copy
543
544template <class _RAIter,
545          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
546__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
547copy(_RAIter __f,
548     _RAIter __l,
549     __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
550     typename enable_if<__is_random_access_iterator<_RAIter>::value>::type*)
551{
552    typedef typename __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::difference_type difference_type;
553    typedef typename __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::pointer pointer;
554    const difference_type __block_size = __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::__block_size;
555    while (__f != __l)
556    {
557        pointer __rb = __r.__ptr_;
558        pointer __re = *__r.__m_iter_ + __block_size;
559        difference_type __bs = __re - __rb;
560        difference_type __n = __l - __f;
561        _RAIter __m = __l;
562        if (__n > __bs)
563        {
564            __n = __bs;
565            __m = __f + __n;
566        }
567        _VSTD::copy(__f, __m, __rb);
568        __f = __m;
569        __r += __n;
570    }
571    return __r;
572}
573
574template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
575          class _OutputIterator>
576_OutputIterator
577copy(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
578     __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
579     _OutputIterator __r)
580{
581    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::difference_type difference_type;
582    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::pointer pointer;
583    const difference_type __block_size = __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::__block_size;
584    difference_type __n = __l - __f;
585    while (__n > 0)
586    {
587        pointer __fb = __f.__ptr_;
588        pointer __fe = *__f.__m_iter_ + __block_size;
589        difference_type __bs = __fe - __fb;
590        if (__bs > __n)
591        {
592            __bs = __n;
593            __fe = __fb + __bs;
594        }
595        __r = _VSTD::copy(__fb, __fe, __r);
596        __n -= __bs;
597        __f += __bs;
598    }
599    return __r;
600}
601
602template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
603          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
604__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
605copy(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
606     __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
607     __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r)
608{
609    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::difference_type difference_type;
610    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::pointer pointer;
611    const difference_type __block_size = __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::__block_size;
612    difference_type __n = __l - __f;
613    while (__n > 0)
614    {
615        pointer __fb = __f.__ptr_;
616        pointer __fe = *__f.__m_iter_ + __block_size;
617        difference_type __bs = __fe - __fb;
618        if (__bs > __n)
619        {
620            __bs = __n;
621            __fe = __fb + __bs;
622        }
623        __r = _VSTD::copy(__fb, __fe, __r);
624        __n -= __bs;
625        __f += __bs;
626    }
627    return __r;
628}
629
630// copy_backward
631
632template <class _RAIter,
633          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
634__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
635copy_backward(_RAIter __f,
636              _RAIter __l,
637              __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
638              typename enable_if<__is_random_access_iterator<_RAIter>::value>::type*)
639{
640    typedef typename __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::difference_type difference_type;
641    typedef typename __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::pointer pointer;
642    while (__f != __l)
643    {
644        __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __rp = _VSTD::prev(__r);
645        pointer __rb = *__rp.__m_iter_;
646        pointer __re = __rp.__ptr_ + 1;
647        difference_type __bs = __re - __rb;
648        difference_type __n = __l - __f;
649        _RAIter __m = __f;
650        if (__n > __bs)
651        {
652            __n = __bs;
653            __m = __l - __n;
654        }
655        _VSTD::copy_backward(__m, __l, __re);
656        __l = __m;
657        __r -= __n;
658    }
659    return __r;
660}
661
662template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
663          class _OutputIterator>
664_OutputIterator
665copy_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
666              __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
667              _OutputIterator __r)
668{
669    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::difference_type difference_type;
670    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::pointer pointer;
671    difference_type __n = __l - __f;
672    while (__n > 0)
673    {
674        --__l;
675        pointer __lb = *__l.__m_iter_;
676        pointer __le = __l.__ptr_ + 1;
677        difference_type __bs = __le - __lb;
678        if (__bs > __n)
679        {
680            __bs = __n;
681            __lb = __le - __bs;
682        }
683        __r = _VSTD::copy_backward(__lb, __le, __r);
684        __n -= __bs;
685        __l -= __bs - 1;
686    }
687    return __r;
688}
689
690template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
691          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
692__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
693copy_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
694              __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
695              __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r)
696{
697    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::difference_type difference_type;
698    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::pointer pointer;
699    difference_type __n = __l - __f;
700    while (__n > 0)
701    {
702        --__l;
703        pointer __lb = *__l.__m_iter_;
704        pointer __le = __l.__ptr_ + 1;
705        difference_type __bs = __le - __lb;
706        if (__bs > __n)
707        {
708            __bs = __n;
709            __lb = __le - __bs;
710        }
711        __r = _VSTD::copy_backward(__lb, __le, __r);
712        __n -= __bs;
713        __l -= __bs - 1;
714    }
715    return __r;
716}
717
718// move
719
720template <class _RAIter,
721          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
722__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
723move(_RAIter __f,
724     _RAIter __l,
725     __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
726     typename enable_if<__is_random_access_iterator<_RAIter>::value>::type*)
727{
728    typedef typename __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::difference_type difference_type;
729    typedef typename __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::pointer pointer;
730    const difference_type __block_size = __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::__block_size;
731    while (__f != __l)
732    {
733        pointer __rb = __r.__ptr_;
734        pointer __re = *__r.__m_iter_ + __block_size;
735        difference_type __bs = __re - __rb;
736        difference_type __n = __l - __f;
737        _RAIter __m = __l;
738        if (__n > __bs)
739        {
740            __n = __bs;
741            __m = __f + __n;
742        }
743        _VSTD::move(__f, __m, __rb);
744        __f = __m;
745        __r += __n;
746    }
747    return __r;
748}
749
750template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
751          class _OutputIterator>
752_OutputIterator
753move(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
754     __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
755     _OutputIterator __r)
756{
757    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::difference_type difference_type;
758    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::pointer pointer;
759    const difference_type __block_size = __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::__block_size;
760    difference_type __n = __l - __f;
761    while (__n > 0)
762    {
763        pointer __fb = __f.__ptr_;
764        pointer __fe = *__f.__m_iter_ + __block_size;
765        difference_type __bs = __fe - __fb;
766        if (__bs > __n)
767        {
768            __bs = __n;
769            __fe = __fb + __bs;
770        }
771        __r = _VSTD::move(__fb, __fe, __r);
772        __n -= __bs;
773        __f += __bs;
774    }
775    return __r;
776}
777
778template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
779          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
780__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
781move(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
782     __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
783     __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r)
784{
785    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::difference_type difference_type;
786    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::pointer pointer;
787    const difference_type __block_size = __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::__block_size;
788    difference_type __n = __l - __f;
789    while (__n > 0)
790    {
791        pointer __fb = __f.__ptr_;
792        pointer __fe = *__f.__m_iter_ + __block_size;
793        difference_type __bs = __fe - __fb;
794        if (__bs > __n)
795        {
796            __bs = __n;
797            __fe = __fb + __bs;
798        }
799        __r = _VSTD::move(__fb, __fe, __r);
800        __n -= __bs;
801        __f += __bs;
802    }
803    return __r;
804}
805
806// move_backward
807
808template <class _RAIter,
809          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
810__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
811move_backward(_RAIter __f,
812              _RAIter __l,
813              __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r,
814              typename enable_if<__is_random_access_iterator<_RAIter>::value>::type*)
815{
816    typedef typename __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::difference_type difference_type;
817    typedef typename __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>::pointer pointer;
818    while (__f != __l)
819    {
820        __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __rp = _VSTD::prev(__r);
821        pointer __rb = *__rp.__m_iter_;
822        pointer __re = __rp.__ptr_ + 1;
823        difference_type __bs = __re - __rb;
824        difference_type __n = __l - __f;
825        _RAIter __m = __f;
826        if (__n > __bs)
827        {
828            __n = __bs;
829            __m = __l - __n;
830        }
831        _VSTD::move_backward(__m, __l, __re);
832        __l = __m;
833        __r -= __n;
834    }
835    return __r;
836}
837
838template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
839          class _OutputIterator>
840_OutputIterator
841move_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
842              __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
843              _OutputIterator __r)
844{
845    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::difference_type difference_type;
846    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::pointer pointer;
847    difference_type __n = __l - __f;
848    while (__n > 0)
849    {
850        --__l;
851        pointer __lb = *__l.__m_iter_;
852        pointer __le = __l.__ptr_ + 1;
853        difference_type __bs = __le - __lb;
854        if (__bs > __n)
855        {
856            __bs = __n;
857            __lb = __le - __bs;
858        }
859        __r = _VSTD::move_backward(__lb, __le, __r);
860        __n -= __bs;
861        __l -= __bs - 1;
862    }
863    return __r;
864}
865
866template <class _V1, class _P1, class _R1, class _M1, class _D1, _D1 _B1,
867          class _V2, class _P2, class _R2, class _M2, class _D2, _D2 _B2>
868__deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2>
869move_backward(__deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __f,
870              __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1> __l,
871              __deque_iterator<_V2, _P2, _R2, _M2, _D2, _B2> __r)
872{
873    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::difference_type difference_type;
874    typedef typename __deque_iterator<_V1, _P1, _R1, _M1, _D1, _B1>::pointer pointer;
875    difference_type __n = __l - __f;
876    while (__n > 0)
877    {
878        --__l;
879        pointer __lb = *__l.__m_iter_;
880        pointer __le = __l.__ptr_ + 1;
881        difference_type __bs = __le - __lb;
882        if (__bs > __n)
883        {
884            __bs = __n;
885            __lb = __le - __bs;
886        }
887        __r = _VSTD::move_backward(__lb, __le, __r);
888        __n -= __bs;
889        __l -= __bs - 1;
890    }
891    return __r;
892}
893
894template <bool>
895class __deque_base_common
896{
897protected:
898    void __throw_length_error() const;
899    void __throw_out_of_range() const;
900};
901
902template <bool __b>
903void
904__deque_base_common<__b>::__throw_length_error() const
905{
906#ifndef _LIBCPP_NO_EXCEPTIONS
907    throw length_error("deque");
908#endif
909}
910
911template <bool __b>
912void
913__deque_base_common<__b>::__throw_out_of_range() const
914{
915#ifndef _LIBCPP_NO_EXCEPTIONS
916    throw out_of_range("deque");
917#endif
918}
919
920template <class _Tp, class _Allocator>
921class __deque_base
922    : protected __deque_base_common<true>
923{
924    __deque_base(const __deque_base& __c);
925    __deque_base& operator=(const __deque_base& __c);
926protected:
927    typedef _Tp                                      value_type;
928    typedef _Allocator                               allocator_type;
929    typedef allocator_traits<allocator_type>         __alloc_traits;
930    typedef value_type&                              reference;
931    typedef const value_type&                        const_reference;
932    typedef typename __alloc_traits::size_type       size_type;
933    typedef typename __alloc_traits::difference_type difference_type;
934    typedef typename __alloc_traits::pointer         pointer;
935    typedef typename __alloc_traits::const_pointer   const_pointer;
936
937    static const difference_type __block_size;
938
939    typedef typename __rebind_alloc_helper<__alloc_traits, pointer>::type __pointer_allocator;
940    typedef allocator_traits<__pointer_allocator>        __map_traits;
941    typedef typename __map_traits::pointer               __map_pointer;
942    typedef typename __rebind_alloc_helper<__alloc_traits, const_pointer>::type __const_pointer_allocator;
943    typedef typename allocator_traits<__const_pointer_allocator>::const_pointer __map_const_pointer;
944    typedef __split_buffer<pointer, __pointer_allocator> __map;
945
946    typedef __deque_iterator<value_type, pointer, reference, __map_pointer,
947                             difference_type>    iterator;
948    typedef __deque_iterator<value_type, const_pointer, const_reference, __map_const_pointer,
949                             difference_type>    const_iterator;
950
951    __map __map_;
952    size_type __start_;
953    __compressed_pair<size_type, allocator_type> __size_;
954
955    iterator       begin() _NOEXCEPT;
956    const_iterator begin() const _NOEXCEPT;
957    iterator       end() _NOEXCEPT;
958    const_iterator end() const _NOEXCEPT;
959
960    _LIBCPP_INLINE_VISIBILITY size_type&            size()          {return __size_.first();}
961    _LIBCPP_INLINE_VISIBILITY
962    const size_type& size() const _NOEXCEPT {return __size_.first();}
963    _LIBCPP_INLINE_VISIBILITY allocator_type&       __alloc()       {return __size_.second();}
964    _LIBCPP_INLINE_VISIBILITY
965    const allocator_type& __alloc() const _NOEXCEPT {return __size_.second();}
966
967    _LIBCPP_INLINE_VISIBILITY
968    __deque_base()
969        _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value);
970    _LIBCPP_INLINE_VISIBILITY
971    explicit __deque_base(const allocator_type& __a);
972public:
973    ~__deque_base();
974
975#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
976
977    __deque_base(__deque_base&& __c)
978        _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value);
979    __deque_base(__deque_base&& __c, const allocator_type& __a);
980
981#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
982    void swap(__deque_base& __c)
983#if _LIBCPP_STD_VER >= 14
984        _NOEXCEPT;
985#else
986        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
987                    __is_nothrow_swappable<allocator_type>::value);
988#endif
989protected:
990    void clear() _NOEXCEPT;
991
992    bool __invariants() const;
993
994    _LIBCPP_INLINE_VISIBILITY
995    void __move_assign(__deque_base& __c)
996        _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value &&
997                   is_nothrow_move_assignable<allocator_type>::value)
998    {
999        __map_ = _VSTD::move(__c.__map_);
1000        __start_ = __c.__start_;
1001        size() = __c.size();
1002        __move_assign_alloc(__c);
1003        __c.__start_ = __c.size() = 0;
1004    }
1005
1006    _LIBCPP_INLINE_VISIBILITY
1007    void __move_assign_alloc(__deque_base& __c)
1008        _NOEXCEPT_(!__alloc_traits::propagate_on_container_move_assignment::value ||
1009                   is_nothrow_move_assignable<allocator_type>::value)
1010        {__move_assign_alloc(__c, integral_constant<bool,
1011                      __alloc_traits::propagate_on_container_move_assignment::value>());}
1012
1013private:
1014    _LIBCPP_INLINE_VISIBILITY
1015    void __move_assign_alloc(__deque_base& __c, true_type)
1016        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
1017        {
1018            __alloc() = _VSTD::move(__c.__alloc());
1019        }
1020
1021    _LIBCPP_INLINE_VISIBILITY
1022    void __move_assign_alloc(__deque_base&, false_type) _NOEXCEPT
1023        {}
1024};
1025
1026template <class _Tp, class _Allocator>
1027const typename __deque_base<_Tp, _Allocator>::difference_type
1028    __deque_base<_Tp, _Allocator>::__block_size =
1029        __deque_block_size<value_type, difference_type>::value;
1030
1031template <class _Tp, class _Allocator>
1032bool
1033__deque_base<_Tp, _Allocator>::__invariants() const
1034{
1035    if (!__map_.__invariants())
1036        return false;
1037    if (__map_.size() >= size_type(-1) / __block_size)
1038        return false;
1039    for (typename __map::const_iterator __i = __map_.begin(), __e = __map_.end();
1040         __i != __e; ++__i)
1041        if (*__i == nullptr)
1042            return false;
1043    if (__map_.size() != 0)
1044    {
1045        if (size() >= __map_.size() * __block_size)
1046            return false;
1047        if (__start_ >= __map_.size() * __block_size - size())
1048            return false;
1049    }
1050    else
1051    {
1052        if (size() != 0)
1053            return false;
1054        if (__start_ != 0)
1055            return false;
1056    }
1057    return true;
1058}
1059
1060template <class _Tp, class _Allocator>
1061typename __deque_base<_Tp, _Allocator>::iterator
1062__deque_base<_Tp, _Allocator>::begin() _NOEXCEPT
1063{
1064    __map_pointer __mp = __map_.begin() + __start_ / __block_size;
1065    return iterator(__mp, __map_.empty() ? 0 : *__mp + __start_ % __block_size);
1066}
1067
1068template <class _Tp, class _Allocator>
1069typename __deque_base<_Tp, _Allocator>::const_iterator
1070__deque_base<_Tp, _Allocator>::begin() const _NOEXCEPT
1071{
1072    __map_const_pointer __mp = static_cast<__map_const_pointer>(__map_.begin() + __start_ / __block_size);
1073    return const_iterator(__mp, __map_.empty() ? 0 : *__mp + __start_ % __block_size);
1074}
1075
1076template <class _Tp, class _Allocator>
1077typename __deque_base<_Tp, _Allocator>::iterator
1078__deque_base<_Tp, _Allocator>::end() _NOEXCEPT
1079{
1080    size_type __p = size() + __start_;
1081    __map_pointer __mp = __map_.begin() + __p / __block_size;
1082    return iterator(__mp, __map_.empty() ? 0 : *__mp + __p % __block_size);
1083}
1084
1085template <class _Tp, class _Allocator>
1086typename __deque_base<_Tp, _Allocator>::const_iterator
1087__deque_base<_Tp, _Allocator>::end() const _NOEXCEPT
1088{
1089    size_type __p = size() + __start_;
1090    __map_const_pointer __mp = static_cast<__map_const_pointer>(__map_.begin() + __p / __block_size);
1091    return const_iterator(__mp, __map_.empty() ? 0 : *__mp + __p % __block_size);
1092}
1093
1094template <class _Tp, class _Allocator>
1095inline
1096__deque_base<_Tp, _Allocator>::__deque_base()
1097    _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
1098    : __start_(0), __size_(0) {}
1099
1100template <class _Tp, class _Allocator>
1101inline
1102__deque_base<_Tp, _Allocator>::__deque_base(const allocator_type& __a)
1103    : __map_(__pointer_allocator(__a)), __start_(0), __size_(0, __a) {}
1104
1105template <class _Tp, class _Allocator>
1106__deque_base<_Tp, _Allocator>::~__deque_base()
1107{
1108    clear();
1109    typename __map::iterator __i = __map_.begin();
1110    typename __map::iterator __e = __map_.end();
1111    for (; __i != __e; ++__i)
1112        __alloc_traits::deallocate(__alloc(), *__i, __block_size);
1113}
1114
1115#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1116
1117template <class _Tp, class _Allocator>
1118__deque_base<_Tp, _Allocator>::__deque_base(__deque_base&& __c)
1119    _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
1120    : __map_(_VSTD::move(__c.__map_)),
1121      __start_(_VSTD::move(__c.__start_)),
1122      __size_(_VSTD::move(__c.__size_))
1123{
1124    __c.__start_ = 0;
1125    __c.size() = 0;
1126}
1127
1128template <class _Tp, class _Allocator>
1129__deque_base<_Tp, _Allocator>::__deque_base(__deque_base&& __c, const allocator_type& __a)
1130    : __map_(_VSTD::move(__c.__map_), __pointer_allocator(__a)),
1131      __start_(_VSTD::move(__c.__start_)),
1132      __size_(_VSTD::move(__c.size()), __a)
1133{
1134    if (__a == __c.__alloc())
1135    {
1136        __c.__start_ = 0;
1137        __c.size() = 0;
1138    }
1139    else
1140    {
1141        __map_.clear();
1142        __start_ = 0;
1143        size() = 0;
1144    }
1145}
1146
1147#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1148
1149template <class _Tp, class _Allocator>
1150void
1151__deque_base<_Tp, _Allocator>::swap(__deque_base& __c)
1152#if _LIBCPP_STD_VER >= 14
1153        _NOEXCEPT
1154#else
1155        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
1156                    __is_nothrow_swappable<allocator_type>::value)
1157#endif
1158{
1159    __map_.swap(__c.__map_);
1160    _VSTD::swap(__start_, __c.__start_);
1161    _VSTD::swap(size(), __c.size());
1162    __swap_allocator(__alloc(), __c.__alloc());
1163}
1164
1165template <class _Tp, class _Allocator>
1166void
1167__deque_base<_Tp, _Allocator>::clear() _NOEXCEPT
1168{
1169    allocator_type& __a = __alloc();
1170    for (iterator __i = begin(), __e = end(); __i != __e; ++__i)
1171        __alloc_traits::destroy(__a, _VSTD::addressof(*__i));
1172    size() = 0;
1173    while (__map_.size() > 2)
1174    {
1175        __alloc_traits::deallocate(__a, __map_.front(), __block_size);
1176        __map_.pop_front();
1177    }
1178    switch (__map_.size())
1179    {
1180    case 1:
1181        __start_ = __block_size / 2;
1182        break;
1183    case 2:
1184        __start_ = __block_size;
1185        break;
1186    }
1187}
1188
1189template <class _Tp, class _Allocator /*= allocator<_Tp>*/>
1190class _LIBCPP_TYPE_VIS_ONLY deque
1191    : private __deque_base<_Tp, _Allocator>
1192{
1193public:
1194    // types:
1195
1196    typedef _Tp value_type;
1197    typedef _Allocator allocator_type;
1198
1199    typedef __deque_base<value_type, allocator_type> __base;
1200
1201    typedef typename __base::__alloc_traits        __alloc_traits;
1202    typedef typename __base::reference             reference;
1203    typedef typename __base::const_reference       const_reference;
1204    typedef typename __base::iterator              iterator;
1205    typedef typename __base::const_iterator        const_iterator;
1206    typedef typename __base::size_type             size_type;
1207    typedef typename __base::difference_type       difference_type;
1208
1209    typedef typename __base::pointer               pointer;
1210    typedef typename __base::const_pointer         const_pointer;
1211    typedef _VSTD::reverse_iterator<iterator>       reverse_iterator;
1212    typedef _VSTD::reverse_iterator<const_iterator> const_reverse_iterator;
1213
1214    // construct/copy/destroy:
1215    _LIBCPP_INLINE_VISIBILITY
1216    deque()
1217        _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
1218        {}
1219    _LIBCPP_INLINE_VISIBILITY explicit deque(const allocator_type& __a) : __base(__a) {}
1220    explicit deque(size_type __n);
1221#if _LIBCPP_STD_VER > 11
1222    explicit deque(size_type __n, const _Allocator& __a);
1223#endif
1224    deque(size_type __n, const value_type& __v);
1225    deque(size_type __n, const value_type& __v, const allocator_type& __a);
1226    template <class _InputIter>
1227        deque(_InputIter __f, _InputIter __l,
1228              typename enable_if<__is_input_iterator<_InputIter>::value>::type* = 0);
1229    template <class _InputIter>
1230        deque(_InputIter __f, _InputIter __l, const allocator_type& __a,
1231              typename enable_if<__is_input_iterator<_InputIter>::value>::type* = 0);
1232    deque(const deque& __c);
1233    deque(const deque& __c, const allocator_type& __a);
1234#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1235    deque(initializer_list<value_type> __il);
1236    deque(initializer_list<value_type> __il, const allocator_type& __a);
1237#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1238
1239    deque& operator=(const deque& __c);
1240#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1241    _LIBCPP_INLINE_VISIBILITY
1242    deque& operator=(initializer_list<value_type> __il) {assign(__il); return *this;}
1243#endif   // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1244
1245#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1246    _LIBCPP_INLINE_VISIBILITY
1247    deque(deque&& __c) _NOEXCEPT_(is_nothrow_move_constructible<__base>::value);
1248    _LIBCPP_INLINE_VISIBILITY
1249    deque(deque&& __c, const allocator_type& __a);
1250    _LIBCPP_INLINE_VISIBILITY
1251    deque& operator=(deque&& __c)
1252        _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value &&
1253                   is_nothrow_move_assignable<allocator_type>::value);
1254#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1255
1256    template <class _InputIter>
1257        void assign(_InputIter __f, _InputIter __l,
1258                    typename enable_if<__is_input_iterator<_InputIter>::value &&
1259                                      !__is_random_access_iterator<_InputIter>::value>::type* = 0);
1260    template <class _RAIter>
1261        void assign(_RAIter __f, _RAIter __l,
1262                    typename enable_if<__is_random_access_iterator<_RAIter>::value>::type* = 0);
1263    void assign(size_type __n, const value_type& __v);
1264#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1265    _LIBCPP_INLINE_VISIBILITY
1266    void assign(initializer_list<value_type> __il) {assign(__il.begin(), __il.end());}
1267#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1268
1269    _LIBCPP_INLINE_VISIBILITY
1270    allocator_type get_allocator() const _NOEXCEPT;
1271
1272    // iterators:
1273
1274    _LIBCPP_INLINE_VISIBILITY
1275    iterator       begin() _NOEXCEPT       {return __base::begin();}
1276    _LIBCPP_INLINE_VISIBILITY
1277    const_iterator begin() const _NOEXCEPT {return __base::begin();}
1278    _LIBCPP_INLINE_VISIBILITY
1279    iterator       end() _NOEXCEPT         {return __base::end();}
1280    _LIBCPP_INLINE_VISIBILITY
1281    const_iterator end()   const _NOEXCEPT {return __base::end();}
1282
1283    _LIBCPP_INLINE_VISIBILITY
1284    reverse_iterator       rbegin() _NOEXCEPT
1285        {return       reverse_iterator(__base::end());}
1286    _LIBCPP_INLINE_VISIBILITY
1287    const_reverse_iterator rbegin() const _NOEXCEPT
1288        {return const_reverse_iterator(__base::end());}
1289    _LIBCPP_INLINE_VISIBILITY
1290    reverse_iterator       rend() _NOEXCEPT
1291        {return       reverse_iterator(__base::begin());}
1292    _LIBCPP_INLINE_VISIBILITY
1293    const_reverse_iterator rend()   const _NOEXCEPT
1294        {return const_reverse_iterator(__base::begin());}
1295
1296    _LIBCPP_INLINE_VISIBILITY
1297    const_iterator         cbegin()  const _NOEXCEPT
1298        {return __base::begin();}
1299    _LIBCPP_INLINE_VISIBILITY
1300    const_iterator         cend()    const _NOEXCEPT
1301        {return __base::end();}
1302    _LIBCPP_INLINE_VISIBILITY
1303    const_reverse_iterator crbegin() const _NOEXCEPT
1304        {return const_reverse_iterator(__base::end());}
1305    _LIBCPP_INLINE_VISIBILITY
1306    const_reverse_iterator crend()   const _NOEXCEPT
1307        {return const_reverse_iterator(__base::begin());}
1308
1309    // capacity:
1310    _LIBCPP_INLINE_VISIBILITY
1311    size_type size() const _NOEXCEPT {return __base::size();}
1312    _LIBCPP_INLINE_VISIBILITY
1313    size_type max_size() const _NOEXCEPT
1314        {return __alloc_traits::max_size(__base::__alloc());}
1315    void resize(size_type __n);
1316    void resize(size_type __n, const value_type& __v);
1317    void shrink_to_fit() _NOEXCEPT;
1318    _LIBCPP_INLINE_VISIBILITY
1319    bool empty() const _NOEXCEPT {return __base::size() == 0;}
1320
1321    // element access:
1322    _LIBCPP_INLINE_VISIBILITY
1323    reference operator[](size_type __i);
1324    _LIBCPP_INLINE_VISIBILITY
1325    const_reference operator[](size_type __i) const;
1326    _LIBCPP_INLINE_VISIBILITY
1327    reference at(size_type __i);
1328    _LIBCPP_INLINE_VISIBILITY
1329    const_reference at(size_type __i) const;
1330    _LIBCPP_INLINE_VISIBILITY
1331    reference front();
1332    _LIBCPP_INLINE_VISIBILITY
1333    const_reference front() const;
1334    _LIBCPP_INLINE_VISIBILITY
1335    reference back();
1336    _LIBCPP_INLINE_VISIBILITY
1337    const_reference back() const;
1338
1339    // 23.2.2.3 modifiers:
1340    void push_front(const value_type& __v);
1341    void push_back(const value_type& __v);
1342#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1343#ifndef _LIBCPP_HAS_NO_VARIADICS
1344    template <class... _Args> void emplace_front(_Args&&... __args);
1345    template <class... _Args> void emplace_back(_Args&&... __args);
1346    template <class... _Args> iterator emplace(const_iterator __p, _Args&&... __args);
1347#endif  // _LIBCPP_HAS_NO_VARIADICS
1348    void push_front(value_type&& __v);
1349    void push_back(value_type&& __v);
1350    iterator insert(const_iterator __p, value_type&& __v);
1351#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1352    iterator insert(const_iterator __p, const value_type& __v);
1353    iterator insert(const_iterator __p, size_type __n, const value_type& __v);
1354    template <class _InputIter>
1355        iterator insert(const_iterator __p, _InputIter __f, _InputIter __l,
1356                         typename enable_if<__is_input_iterator<_InputIter>::value
1357                                         &&!__is_forward_iterator<_InputIter>::value>::type* = 0);
1358    template <class _ForwardIterator>
1359        iterator insert(const_iterator __p, _ForwardIterator __f, _ForwardIterator __l,
1360                               typename enable_if<__is_forward_iterator<_ForwardIterator>::value
1361                                         &&!__is_bidirectional_iterator<_ForwardIterator>::value>::type* = 0);
1362    template <class _BiIter>
1363        iterator insert(const_iterator __p, _BiIter __f, _BiIter __l,
1364                         typename enable_if<__is_bidirectional_iterator<_BiIter>::value>::type* = 0);
1365#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1366    _LIBCPP_INLINE_VISIBILITY
1367    iterator insert(const_iterator __p, initializer_list<value_type> __il)
1368        {return insert(__p, __il.begin(), __il.end());}
1369#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1370    void pop_front();
1371    void pop_back();
1372    iterator erase(const_iterator __p);
1373    iterator erase(const_iterator __f, const_iterator __l);
1374
1375    _LIBCPP_INLINE_VISIBILITY
1376    void swap(deque& __c)
1377#if _LIBCPP_STD_VER >= 14
1378        _NOEXCEPT;
1379#else
1380        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
1381                   __is_nothrow_swappable<allocator_type>::value);
1382#endif
1383    _LIBCPP_INLINE_VISIBILITY
1384    void clear() _NOEXCEPT;
1385
1386    _LIBCPP_INLINE_VISIBILITY
1387    bool __invariants() const {return __base::__invariants();}
1388private:
1389    typedef typename __base::__map_const_pointer __map_const_pointer;
1390
1391    _LIBCPP_INLINE_VISIBILITY
1392    static size_type __recommend_blocks(size_type __n)
1393    {
1394        return __n / __base::__block_size + (__n % __base::__block_size != 0);
1395    }
1396    _LIBCPP_INLINE_VISIBILITY
1397    size_type __capacity() const
1398    {
1399        return __base::__map_.size() == 0 ? 0 : __base::__map_.size() * __base::__block_size - 1;
1400    }
1401    _LIBCPP_INLINE_VISIBILITY
1402    size_type __front_spare() const
1403    {
1404        return __base::__start_;
1405    }
1406    _LIBCPP_INLINE_VISIBILITY
1407    size_type __back_spare() const
1408    {
1409        return __capacity() - (__base::__start_ + __base::size());
1410    }
1411
1412    template <class _InpIter>
1413        void __append(_InpIter __f, _InpIter __l,
1414                 typename enable_if<__is_input_iterator<_InpIter>::value &&
1415                                   !__is_forward_iterator<_InpIter>::value>::type* = 0);
1416    template <class _ForIter>
1417        void __append(_ForIter __f, _ForIter __l,
1418                      typename enable_if<__is_forward_iterator<_ForIter>::value>::type* = 0);
1419    void __append(size_type __n);
1420    void __append(size_type __n, const value_type& __v);
1421    void __erase_to_end(const_iterator __f);
1422    void __add_front_capacity();
1423    void __add_front_capacity(size_type __n);
1424    void __add_back_capacity();
1425    void __add_back_capacity(size_type __n);
1426    iterator __move_and_check(iterator __f, iterator __l, iterator __r,
1427                              const_pointer& __vt);
1428    iterator __move_backward_and_check(iterator __f, iterator __l, iterator __r,
1429                                       const_pointer& __vt);
1430    void __move_construct_and_check(iterator __f, iterator __l,
1431                                    iterator __r, const_pointer& __vt);
1432    void __move_construct_backward_and_check(iterator __f, iterator __l,
1433                                             iterator __r, const_pointer& __vt);
1434
1435    _LIBCPP_INLINE_VISIBILITY
1436    void __copy_assign_alloc(const deque& __c)
1437        {__copy_assign_alloc(__c, integral_constant<bool,
1438                      __alloc_traits::propagate_on_container_copy_assignment::value>());}
1439
1440    _LIBCPP_INLINE_VISIBILITY
1441    void __copy_assign_alloc(const deque& __c, true_type)
1442        {
1443            if (__base::__alloc() != __c.__alloc())
1444            {
1445                clear();
1446                shrink_to_fit();
1447            }
1448            __base::__alloc() = __c.__alloc();
1449            __base::__map_.__alloc() = __c.__map_.__alloc();
1450        }
1451
1452    _LIBCPP_INLINE_VISIBILITY
1453    void __copy_assign_alloc(const deque&, false_type)
1454        {}
1455
1456    void __move_assign(deque& __c, true_type)
1457        _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
1458    void __move_assign(deque& __c, false_type);
1459};
1460
1461template <class _Tp, class _Allocator>
1462deque<_Tp, _Allocator>::deque(size_type __n)
1463{
1464    if (__n > 0)
1465        __append(__n);
1466}
1467
1468#if _LIBCPP_STD_VER > 11
1469template <class _Tp, class _Allocator>
1470deque<_Tp, _Allocator>::deque(size_type __n, const _Allocator& __a)
1471    : __base(__a)
1472{
1473    if (__n > 0)
1474        __append(__n);
1475}
1476#endif
1477
1478template <class _Tp, class _Allocator>
1479deque<_Tp, _Allocator>::deque(size_type __n, const value_type& __v)
1480{
1481    if (__n > 0)
1482        __append(__n, __v);
1483}
1484
1485template <class _Tp, class _Allocator>
1486deque<_Tp, _Allocator>::deque(size_type __n, const value_type& __v, const allocator_type& __a)
1487    : __base(__a)
1488{
1489    if (__n > 0)
1490        __append(__n, __v);
1491}
1492
1493template <class _Tp, class _Allocator>
1494template <class _InputIter>
1495deque<_Tp, _Allocator>::deque(_InputIter __f, _InputIter __l,
1496              typename enable_if<__is_input_iterator<_InputIter>::value>::type*)
1497{
1498    __append(__f, __l);
1499}
1500
1501template <class _Tp, class _Allocator>
1502template <class _InputIter>
1503deque<_Tp, _Allocator>::deque(_InputIter __f, _InputIter __l, const allocator_type& __a,
1504              typename enable_if<__is_input_iterator<_InputIter>::value>::type*)
1505    : __base(__a)
1506{
1507    __append(__f, __l);
1508}
1509
1510template <class _Tp, class _Allocator>
1511deque<_Tp, _Allocator>::deque(const deque& __c)
1512    : __base(__alloc_traits::select_on_container_copy_construction(__c.__alloc()))
1513{
1514    __append(__c.begin(), __c.end());
1515}
1516
1517template <class _Tp, class _Allocator>
1518deque<_Tp, _Allocator>::deque(const deque& __c, const allocator_type& __a)
1519    : __base(__a)
1520{
1521    __append(__c.begin(), __c.end());
1522}
1523
1524#ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1525
1526template <class _Tp, class _Allocator>
1527deque<_Tp, _Allocator>::deque(initializer_list<value_type> __il)
1528{
1529    __append(__il.begin(), __il.end());
1530}
1531
1532template <class _Tp, class _Allocator>
1533deque<_Tp, _Allocator>::deque(initializer_list<value_type> __il, const allocator_type& __a)
1534    : __base(__a)
1535{
1536    __append(__il.begin(), __il.end());
1537}
1538
1539#endif  // _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
1540
1541template <class _Tp, class _Allocator>
1542deque<_Tp, _Allocator>&
1543deque<_Tp, _Allocator>::operator=(const deque& __c)
1544{
1545    if (this != &__c)
1546    {
1547        __copy_assign_alloc(__c);
1548        assign(__c.begin(), __c.end());
1549    }
1550    return *this;
1551}
1552
1553#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1554
1555template <class _Tp, class _Allocator>
1556inline
1557deque<_Tp, _Allocator>::deque(deque&& __c)
1558    _NOEXCEPT_(is_nothrow_move_constructible<__base>::value)
1559    : __base(_VSTD::move(__c))
1560{
1561}
1562
1563template <class _Tp, class _Allocator>
1564inline
1565deque<_Tp, _Allocator>::deque(deque&& __c, const allocator_type& __a)
1566    : __base(_VSTD::move(__c), __a)
1567{
1568    if (__a != __c.__alloc())
1569    {
1570        typedef move_iterator<iterator> _Ip;
1571        assign(_Ip(__c.begin()), _Ip(__c.end()));
1572    }
1573}
1574
1575template <class _Tp, class _Allocator>
1576inline
1577deque<_Tp, _Allocator>&
1578deque<_Tp, _Allocator>::operator=(deque&& __c)
1579        _NOEXCEPT_(__alloc_traits::propagate_on_container_move_assignment::value &&
1580                   is_nothrow_move_assignable<allocator_type>::value)
1581{
1582    __move_assign(__c, integral_constant<bool,
1583          __alloc_traits::propagate_on_container_move_assignment::value>());
1584    return *this;
1585}
1586
1587template <class _Tp, class _Allocator>
1588void
1589deque<_Tp, _Allocator>::__move_assign(deque& __c, false_type)
1590{
1591    if (__base::__alloc() != __c.__alloc())
1592    {
1593        typedef move_iterator<iterator> _Ip;
1594        assign(_Ip(__c.begin()), _Ip(__c.end()));
1595    }
1596    else
1597        __move_assign(__c, true_type());
1598}
1599
1600template <class _Tp, class _Allocator>
1601void
1602deque<_Tp, _Allocator>::__move_assign(deque& __c, true_type)
1603    _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
1604{
1605    clear();
1606    shrink_to_fit();
1607    __base::__move_assign(__c);
1608}
1609
1610#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1611
1612template <class _Tp, class _Allocator>
1613template <class _InputIter>
1614void
1615deque<_Tp, _Allocator>::assign(_InputIter __f, _InputIter __l,
1616                               typename enable_if<__is_input_iterator<_InputIter>::value &&
1617                                                 !__is_random_access_iterator<_InputIter>::value>::type*)
1618{
1619    iterator __i = __base::begin();
1620    iterator __e = __base::end();
1621    for (; __f != __l && __i != __e; ++__f, (void) ++__i)
1622        *__i = *__f;
1623    if (__f != __l)
1624        __append(__f, __l);
1625    else
1626        __erase_to_end(__i);
1627}
1628
1629template <class _Tp, class _Allocator>
1630template <class _RAIter>
1631void
1632deque<_Tp, _Allocator>::assign(_RAIter __f, _RAIter __l,
1633                               typename enable_if<__is_random_access_iterator<_RAIter>::value>::type*)
1634{
1635    if (static_cast<size_type>(__l - __f) > __base::size())
1636    {
1637        _RAIter __m = __f + __base::size();
1638        _VSTD::copy(__f, __m, __base::begin());
1639        __append(__m, __l);
1640    }
1641    else
1642        __erase_to_end(_VSTD::copy(__f, __l, __base::begin()));
1643}
1644
1645template <class _Tp, class _Allocator>
1646void
1647deque<_Tp, _Allocator>::assign(size_type __n, const value_type& __v)
1648{
1649    if (__n > __base::size())
1650    {
1651        _VSTD::fill_n(__base::begin(), __base::size(), __v);
1652        __n -= __base::size();
1653        __append(__n, __v);
1654    }
1655    else
1656        __erase_to_end(_VSTD::fill_n(__base::begin(), __n, __v));
1657}
1658
1659template <class _Tp, class _Allocator>
1660inline
1661_Allocator
1662deque<_Tp, _Allocator>::get_allocator() const _NOEXCEPT
1663{
1664    return __base::__alloc();
1665}
1666
1667template <class _Tp, class _Allocator>
1668void
1669deque<_Tp, _Allocator>::resize(size_type __n)
1670{
1671    if (__n > __base::size())
1672        __append(__n - __base::size());
1673    else if (__n < __base::size())
1674        __erase_to_end(__base::begin() + __n);
1675}
1676
1677template <class _Tp, class _Allocator>
1678void
1679deque<_Tp, _Allocator>::resize(size_type __n, const value_type& __v)
1680{
1681    if (__n > __base::size())
1682        __append(__n - __base::size(), __v);
1683    else if (__n < __base::size())
1684        __erase_to_end(__base::begin() + __n);
1685}
1686
1687template <class _Tp, class _Allocator>
1688void
1689deque<_Tp, _Allocator>::shrink_to_fit() _NOEXCEPT
1690{
1691    allocator_type& __a = __base::__alloc();
1692    if (empty())
1693    {
1694        while (__base::__map_.size() > 0)
1695        {
1696            __alloc_traits::deallocate(__a, __base::__map_.back(), __base::__block_size);
1697            __base::__map_.pop_back();
1698        }
1699        __base::__start_ = 0;
1700    }
1701    else
1702    {
1703        if (__front_spare() >= __base::__block_size)
1704        {
1705            __alloc_traits::deallocate(__a, __base::__map_.front(), __base::__block_size);
1706            __base::__map_.pop_front();
1707            __base::__start_ -= __base::__block_size;
1708        }
1709        if (__back_spare() >= __base::__block_size)
1710        {
1711            __alloc_traits::deallocate(__a, __base::__map_.back(), __base::__block_size);
1712            __base::__map_.pop_back();
1713        }
1714    }
1715    __base::__map_.shrink_to_fit();
1716}
1717
1718template <class _Tp, class _Allocator>
1719inline
1720typename deque<_Tp, _Allocator>::reference
1721deque<_Tp, _Allocator>::operator[](size_type __i)
1722{
1723    size_type __p = __base::__start_ + __i;
1724    return *(*(__base::__map_.begin() + __p / __base::__block_size) + __p % __base::__block_size);
1725}
1726
1727template <class _Tp, class _Allocator>
1728inline
1729typename deque<_Tp, _Allocator>::const_reference
1730deque<_Tp, _Allocator>::operator[](size_type __i) const
1731{
1732    size_type __p = __base::__start_ + __i;
1733    return *(*(__base::__map_.begin() + __p / __base::__block_size) + __p % __base::__block_size);
1734}
1735
1736template <class _Tp, class _Allocator>
1737inline
1738typename deque<_Tp, _Allocator>::reference
1739deque<_Tp, _Allocator>::at(size_type __i)
1740{
1741    if (__i >= __base::size())
1742        __base::__throw_out_of_range();
1743    size_type __p = __base::__start_ + __i;
1744    return *(*(__base::__map_.begin() + __p / __base::__block_size) + __p % __base::__block_size);
1745}
1746
1747template <class _Tp, class _Allocator>
1748inline
1749typename deque<_Tp, _Allocator>::const_reference
1750deque<_Tp, _Allocator>::at(size_type __i) const
1751{
1752    if (__i >= __base::size())
1753        __base::__throw_out_of_range();
1754    size_type __p = __base::__start_ + __i;
1755    return *(*(__base::__map_.begin() + __p / __base::__block_size) + __p % __base::__block_size);
1756}
1757
1758template <class _Tp, class _Allocator>
1759inline
1760typename deque<_Tp, _Allocator>::reference
1761deque<_Tp, _Allocator>::front()
1762{
1763    return *(*(__base::__map_.begin() + __base::__start_ / __base::__block_size)
1764                                      + __base::__start_ % __base::__block_size);
1765}
1766
1767template <class _Tp, class _Allocator>
1768inline
1769typename deque<_Tp, _Allocator>::const_reference
1770deque<_Tp, _Allocator>::front() const
1771{
1772    return *(*(__base::__map_.begin() + __base::__start_ / __base::__block_size)
1773                                      + __base::__start_ % __base::__block_size);
1774}
1775
1776template <class _Tp, class _Allocator>
1777inline
1778typename deque<_Tp, _Allocator>::reference
1779deque<_Tp, _Allocator>::back()
1780{
1781    size_type __p = __base::size() + __base::__start_ - 1;
1782    return *(*(__base::__map_.begin() + __p / __base::__block_size) + __p % __base::__block_size);
1783}
1784
1785template <class _Tp, class _Allocator>
1786inline
1787typename deque<_Tp, _Allocator>::const_reference
1788deque<_Tp, _Allocator>::back() const
1789{
1790    size_type __p = __base::size() + __base::__start_ - 1;
1791    return *(*(__base::__map_.begin() + __p / __base::__block_size) + __p % __base::__block_size);
1792}
1793
1794template <class _Tp, class _Allocator>
1795void
1796deque<_Tp, _Allocator>::push_back(const value_type& __v)
1797{
1798    allocator_type& __a = __base::__alloc();
1799    if (__back_spare() == 0)
1800        __add_back_capacity();
1801    // __back_spare() >= 1
1802    __alloc_traits::construct(__a, _VSTD::addressof(*__base::end()), __v);
1803    ++__base::size();
1804}
1805
1806#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1807
1808template <class _Tp, class _Allocator>
1809void
1810deque<_Tp, _Allocator>::push_back(value_type&& __v)
1811{
1812    allocator_type& __a = __base::__alloc();
1813    if (__back_spare() == 0)
1814        __add_back_capacity();
1815    // __back_spare() >= 1
1816    __alloc_traits::construct(__a, _VSTD::addressof(*__base::end()), _VSTD::move(__v));
1817    ++__base::size();
1818}
1819
1820#ifndef _LIBCPP_HAS_NO_VARIADICS
1821
1822template <class _Tp, class _Allocator>
1823template <class... _Args>
1824void
1825deque<_Tp, _Allocator>::emplace_back(_Args&&... __args)
1826{
1827    allocator_type& __a = __base::__alloc();
1828    if (__back_spare() == 0)
1829        __add_back_capacity();
1830    // __back_spare() >= 1
1831    __alloc_traits::construct(__a, _VSTD::addressof(*__base::end()), _VSTD::forward<_Args>(__args)...);
1832    ++__base::size();
1833}
1834
1835#endif  // _LIBCPP_HAS_NO_VARIADICS
1836#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1837
1838template <class _Tp, class _Allocator>
1839void
1840deque<_Tp, _Allocator>::push_front(const value_type& __v)
1841{
1842    allocator_type& __a = __base::__alloc();
1843    if (__front_spare() == 0)
1844        __add_front_capacity();
1845    // __front_spare() >= 1
1846    __alloc_traits::construct(__a, _VSTD::addressof(*--__base::begin()), __v);
1847    --__base::__start_;
1848    ++__base::size();
1849}
1850
1851#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1852
1853template <class _Tp, class _Allocator>
1854void
1855deque<_Tp, _Allocator>::push_front(value_type&& __v)
1856{
1857    allocator_type& __a = __base::__alloc();
1858    if (__front_spare() == 0)
1859        __add_front_capacity();
1860    // __front_spare() >= 1
1861    __alloc_traits::construct(__a, _VSTD::addressof(*--__base::begin()), _VSTD::move(__v));
1862    --__base::__start_;
1863    ++__base::size();
1864}
1865
1866#ifndef _LIBCPP_HAS_NO_VARIADICS
1867
1868template <class _Tp, class _Allocator>
1869template <class... _Args>
1870void
1871deque<_Tp, _Allocator>::emplace_front(_Args&&... __args)
1872{
1873    allocator_type& __a = __base::__alloc();
1874    if (__front_spare() == 0)
1875        __add_front_capacity();
1876    // __front_spare() >= 1
1877    __alloc_traits::construct(__a, _VSTD::addressof(*--__base::begin()), _VSTD::forward<_Args>(__args)...);
1878    --__base::__start_;
1879    ++__base::size();
1880}
1881
1882#endif  // _LIBCPP_HAS_NO_VARIADICS
1883#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
1884
1885template <class _Tp, class _Allocator>
1886typename deque<_Tp, _Allocator>::iterator
1887deque<_Tp, _Allocator>::insert(const_iterator __p, const value_type& __v)
1888{
1889    size_type __pos = __p - __base::begin();
1890    size_type __to_end = __base::size() - __pos;
1891    allocator_type& __a = __base::__alloc();
1892    if (__pos < __to_end)
1893    {   // insert by shifting things backward
1894        if (__front_spare() == 0)
1895            __add_front_capacity();
1896        // __front_spare() >= 1
1897        if (__pos == 0)
1898        {
1899            __alloc_traits::construct(__a, _VSTD::addressof(*--__base::begin()), __v);
1900            --__base::__start_;
1901            ++__base::size();
1902        }
1903        else
1904        {
1905            const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
1906            iterator __b = __base::begin();
1907            iterator __bm1 = _VSTD::prev(__b);
1908            if (__vt == pointer_traits<const_pointer>::pointer_to(*__b))
1909                __vt = pointer_traits<const_pointer>::pointer_to(*__bm1);
1910            __alloc_traits::construct(__a, _VSTD::addressof(*__bm1), _VSTD::move(*__b));
1911            --__base::__start_;
1912            ++__base::size();
1913            if (__pos > 1)
1914                __b = __move_and_check(_VSTD::next(__b), __b + __pos, __b, __vt);
1915            *__b = *__vt;
1916        }
1917    }
1918    else
1919    {   // insert by shifting things forward
1920        if (__back_spare() == 0)
1921            __add_back_capacity();
1922        // __back_capacity >= 1
1923        size_type __de = __base::size() - __pos;
1924        if (__de == 0)
1925        {
1926            __alloc_traits::construct(__a, _VSTD::addressof(*__base::end()), __v);
1927            ++__base::size();
1928        }
1929        else
1930        {
1931            const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
1932            iterator __e = __base::end();
1933            iterator __em1 = _VSTD::prev(__e);
1934            if (__vt == pointer_traits<const_pointer>::pointer_to(*__em1))
1935                __vt = pointer_traits<const_pointer>::pointer_to(*__e);
1936            __alloc_traits::construct(__a, _VSTD::addressof(*__e), _VSTD::move(*__em1));
1937            ++__base::size();
1938            if (__de > 1)
1939                __e = __move_backward_and_check(__e - __de, __em1, __e, __vt);
1940            *--__e = *__vt;
1941        }
1942    }
1943    return __base::begin() + __pos;
1944}
1945
1946#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
1947
1948template <class _Tp, class _Allocator>
1949typename deque<_Tp, _Allocator>::iterator
1950deque<_Tp, _Allocator>::insert(const_iterator __p, value_type&& __v)
1951{
1952    size_type __pos = __p - __base::begin();
1953    size_type __to_end = __base::size() - __pos;
1954    allocator_type& __a = __base::__alloc();
1955    if (__pos < __to_end)
1956    {   // insert by shifting things backward
1957        if (__front_spare() == 0)
1958            __add_front_capacity();
1959        // __front_spare() >= 1
1960        if (__pos == 0)
1961        {
1962            __alloc_traits::construct(__a, _VSTD::addressof(*--__base::begin()), _VSTD::move(__v));
1963            --__base::__start_;
1964            ++__base::size();
1965        }
1966        else
1967        {
1968            iterator __b = __base::begin();
1969            iterator __bm1 = _VSTD::prev(__b);
1970            __alloc_traits::construct(__a, _VSTD::addressof(*__bm1), _VSTD::move(*__b));
1971            --__base::__start_;
1972            ++__base::size();
1973            if (__pos > 1)
1974                __b = _VSTD::move(_VSTD::next(__b), __b + __pos, __b);
1975            *__b = _VSTD::move(__v);
1976        }
1977    }
1978    else
1979    {   // insert by shifting things forward
1980        if (__back_spare() == 0)
1981            __add_back_capacity();
1982        // __back_capacity >= 1
1983        size_type __de = __base::size() - __pos;
1984        if (__de == 0)
1985        {
1986            __alloc_traits::construct(__a, _VSTD::addressof(*__base::end()), _VSTD::move(__v));
1987            ++__base::size();
1988        }
1989        else
1990        {
1991            iterator __e = __base::end();
1992            iterator __em1 = _VSTD::prev(__e);
1993            __alloc_traits::construct(__a, _VSTD::addressof(*__e), _VSTD::move(*__em1));
1994            ++__base::size();
1995            if (__de > 1)
1996                __e = _VSTD::move_backward(__e - __de, __em1, __e);
1997            *--__e = _VSTD::move(__v);
1998        }
1999    }
2000    return __base::begin() + __pos;
2001}
2002
2003#ifndef _LIBCPP_HAS_NO_VARIADICS
2004
2005template <class _Tp, class _Allocator>
2006template <class... _Args>
2007typename deque<_Tp, _Allocator>::iterator
2008deque<_Tp, _Allocator>::emplace(const_iterator __p, _Args&&... __args)
2009{
2010    size_type __pos = __p - __base::begin();
2011    size_type __to_end = __base::size() - __pos;
2012    allocator_type& __a = __base::__alloc();
2013    if (__pos < __to_end)
2014    {   // insert by shifting things backward
2015        if (__front_spare() == 0)
2016            __add_front_capacity();
2017        // __front_spare() >= 1
2018        if (__pos == 0)
2019        {
2020            __alloc_traits::construct(__a, _VSTD::addressof(*--__base::begin()), _VSTD::forward<_Args>(__args)...);
2021            --__base::__start_;
2022            ++__base::size();
2023        }
2024        else
2025        {
2026            value_type __tmp(_VSTD::forward<_Args>(__args)...);
2027            iterator __b = __base::begin();
2028            iterator __bm1 = _VSTD::prev(__b);
2029            __alloc_traits::construct(__a, _VSTD::addressof(*__bm1), _VSTD::move(*__b));
2030            --__base::__start_;
2031            ++__base::size();
2032            if (__pos > 1)
2033                __b = _VSTD::move(_VSTD::next(__b), __b + __pos, __b);
2034            *__b = _VSTD::move(__tmp);
2035        }
2036    }
2037    else
2038    {   // insert by shifting things forward
2039        if (__back_spare() == 0)
2040            __add_back_capacity();
2041        // __back_capacity >= 1
2042        size_type __de = __base::size() - __pos;
2043        if (__de == 0)
2044        {
2045            __alloc_traits::construct(__a, _VSTD::addressof(*__base::end()), _VSTD::forward<_Args>(__args)...);
2046            ++__base::size();
2047        }
2048        else
2049        {
2050            value_type __tmp(_VSTD::forward<_Args>(__args)...);
2051            iterator __e = __base::end();
2052            iterator __em1 = _VSTD::prev(__e);
2053            __alloc_traits::construct(__a, _VSTD::addressof(*__e), _VSTD::move(*__em1));
2054            ++__base::size();
2055            if (__de > 1)
2056                __e = _VSTD::move_backward(__e - __de, __em1, __e);
2057            *--__e = _VSTD::move(__tmp);
2058        }
2059    }
2060    return __base::begin() + __pos;
2061}
2062
2063#endif  // _LIBCPP_HAS_NO_VARIADICS
2064#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2065
2066template <class _Tp, class _Allocator>
2067typename deque<_Tp, _Allocator>::iterator
2068deque<_Tp, _Allocator>::insert(const_iterator __p, size_type __n, const value_type& __v)
2069{
2070    size_type __pos = __p - __base::begin();
2071    size_type __to_end = __base::size() - __pos;
2072    allocator_type& __a = __base::__alloc();
2073    if (__pos < __to_end)
2074    {   // insert by shifting things backward
2075        if (__n > __front_spare())
2076            __add_front_capacity(__n - __front_spare());
2077        // __n <= __front_spare()
2078        iterator __old_begin = __base::begin();
2079        iterator __i = __old_begin;
2080        if (__n > __pos)
2081        {
2082            for (size_type __m = __n - __pos; __m; --__m, --__base::__start_, ++__base::size())
2083                __alloc_traits::construct(__a, _VSTD::addressof(*--__i), __v);
2084            __n = __pos;
2085        }
2086        if (__n > 0)
2087        {
2088            const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
2089            iterator __obn = __old_begin + __n;
2090            __move_construct_backward_and_check(__old_begin, __obn, __i, __vt);
2091            if (__n < __pos)
2092                __old_begin = __move_and_check(__obn, __old_begin + __pos, __old_begin, __vt);
2093            _VSTD::fill_n(__old_begin, __n, *__vt);
2094        }
2095    }
2096    else
2097    {   // insert by shifting things forward
2098        size_type __back_capacity = __back_spare();
2099        if (__n > __back_capacity)
2100            __add_back_capacity(__n - __back_capacity);
2101        // __n <= __back_capacity
2102        iterator __old_end = __base::end();
2103        iterator __i = __old_end;
2104        size_type __de = __base::size() - __pos;
2105        if (__n > __de)
2106        {
2107            for (size_type __m = __n - __de; __m; --__m, ++__i, ++__base::size())
2108                __alloc_traits::construct(__a, _VSTD::addressof(*__i), __v);
2109            __n = __de;
2110        }
2111        if (__n > 0)
2112        {
2113            const_pointer __vt = pointer_traits<const_pointer>::pointer_to(__v);
2114            iterator __oen = __old_end - __n;
2115            __move_construct_and_check(__oen, __old_end, __i, __vt);
2116            if (__n < __de)
2117                __old_end = __move_backward_and_check(__old_end - __de, __oen, __old_end, __vt);
2118            _VSTD::fill_n(__old_end - __n, __n, *__vt);
2119        }
2120    }
2121    return __base::begin() + __pos;
2122}
2123
2124template <class _Tp, class _Allocator>
2125template <class _InputIter>
2126typename deque<_Tp, _Allocator>::iterator
2127deque<_Tp, _Allocator>::insert(const_iterator __p, _InputIter __f, _InputIter __l,
2128                               typename enable_if<__is_input_iterator<_InputIter>::value
2129                                               &&!__is_forward_iterator<_InputIter>::value>::type*)
2130{
2131    __split_buffer<value_type, allocator_type&> __buf(__base::__alloc());
2132    __buf.__construct_at_end(__f, __l);
2133    typedef typename __split_buffer<value_type, allocator_type&>::iterator __bi;
2134    return insert(__p, move_iterator<__bi>(__buf.begin()), move_iterator<__bi>(__buf.end()));
2135}
2136
2137template <class _Tp, class _Allocator>
2138template <class _ForwardIterator>
2139typename deque<_Tp, _Allocator>::iterator
2140deque<_Tp, _Allocator>::insert(const_iterator __p, _ForwardIterator __f, _ForwardIterator __l,
2141                               typename enable_if<__is_forward_iterator<_ForwardIterator>::value
2142                                               &&!__is_bidirectional_iterator<_ForwardIterator>::value>::type*)
2143{
2144    size_type __n = _VSTD::distance(__f, __l);
2145    __split_buffer<value_type, allocator_type&> __buf(__n, 0, __base::__alloc());
2146    __buf.__construct_at_end(__f, __l);
2147    typedef typename __split_buffer<value_type, allocator_type&>::iterator __fwd;
2148    return insert(__p, move_iterator<__fwd>(__buf.begin()), move_iterator<__fwd>(__buf.end()));
2149}
2150
2151template <class _Tp, class _Allocator>
2152template <class _BiIter>
2153typename deque<_Tp, _Allocator>::iterator
2154deque<_Tp, _Allocator>::insert(const_iterator __p, _BiIter __f, _BiIter __l,
2155                               typename enable_if<__is_bidirectional_iterator<_BiIter>::value>::type*)
2156{
2157    size_type __n = _VSTD::distance(__f, __l);
2158    size_type __pos = __p - __base::begin();
2159    size_type __to_end = __base::size() - __pos;
2160    allocator_type& __a = __base::__alloc();
2161    if (__pos < __to_end)
2162    {   // insert by shifting things backward
2163        if (__n > __front_spare())
2164            __add_front_capacity(__n - __front_spare());
2165        // __n <= __front_spare()
2166        iterator __old_begin = __base::begin();
2167        iterator __i = __old_begin;
2168        _BiIter __m = __f;
2169        if (__n > __pos)
2170        {
2171            __m = __pos < __n / 2 ? _VSTD::prev(__l, __pos) : _VSTD::next(__f, __n - __pos);
2172            for (_BiIter __j = __m; __j != __f; --__base::__start_, ++__base::size())
2173                __alloc_traits::construct(__a, _VSTD::addressof(*--__i), *--__j);
2174            __n = __pos;
2175        }
2176        if (__n > 0)
2177        {
2178            iterator __obn = __old_begin + __n;
2179            for (iterator __j = __obn; __j != __old_begin;)
2180            {
2181                __alloc_traits::construct(__a, _VSTD::addressof(*--__i), _VSTD::move(*--__j));
2182                --__base::__start_;
2183                ++__base::size();
2184            }
2185            if (__n < __pos)
2186                __old_begin = _VSTD::move(__obn, __old_begin + __pos, __old_begin);
2187            _VSTD::copy(__m, __l, __old_begin);
2188        }
2189    }
2190    else
2191    {   // insert by shifting things forward
2192        size_type __back_capacity = __back_spare();
2193        if (__n > __back_capacity)
2194            __add_back_capacity(__n - __back_capacity);
2195        // __n <= __back_capacity
2196        iterator __old_end = __base::end();
2197        iterator __i = __old_end;
2198        _BiIter __m = __l;
2199        size_type __de = __base::size() - __pos;
2200        if (__n > __de)
2201        {
2202            __m = __de < __n / 2 ? _VSTD::next(__f, __de) : _VSTD::prev(__l, __n - __de);
2203            for (_BiIter __j = __m; __j != __l; ++__i, (void) ++__j, ++__base::size())
2204                __alloc_traits::construct(__a, _VSTD::addressof(*__i), *__j);
2205            __n = __de;
2206        }
2207        if (__n > 0)
2208        {
2209            iterator __oen = __old_end - __n;
2210            for (iterator __j = __oen; __j != __old_end; ++__i, ++__j, ++__base::size())
2211                __alloc_traits::construct(__a, _VSTD::addressof(*__i), _VSTD::move(*__j));
2212            if (__n < __de)
2213                __old_end = _VSTD::move_backward(__old_end - __de, __oen, __old_end);
2214            _VSTD::copy_backward(__f, __m, __old_end);
2215        }
2216    }
2217    return __base::begin() + __pos;
2218}
2219
2220template <class _Tp, class _Allocator>
2221template <class _InpIter>
2222void
2223deque<_Tp, _Allocator>::__append(_InpIter __f, _InpIter __l,
2224                                 typename enable_if<__is_input_iterator<_InpIter>::value &&
2225                                                   !__is_forward_iterator<_InpIter>::value>::type*)
2226{
2227    for (; __f != __l; ++__f)
2228        push_back(*__f);
2229}
2230
2231template <class _Tp, class _Allocator>
2232template <class _ForIter>
2233void
2234deque<_Tp, _Allocator>::__append(_ForIter __f, _ForIter __l,
2235                                 typename enable_if<__is_forward_iterator<_ForIter>::value>::type*)
2236{
2237    size_type __n = _VSTD::distance(__f, __l);
2238    allocator_type& __a = __base::__alloc();
2239    size_type __back_capacity = __back_spare();
2240    if (__n > __back_capacity)
2241        __add_back_capacity(__n - __back_capacity);
2242    // __n <= __back_capacity
2243    for (iterator __i = __base::end(); __f != __l; ++__i, (void) ++__f, ++__base::size())
2244        __alloc_traits::construct(__a, _VSTD::addressof(*__i), *__f);
2245}
2246
2247template <class _Tp, class _Allocator>
2248void
2249deque<_Tp, _Allocator>::__append(size_type __n)
2250{
2251    allocator_type& __a = __base::__alloc();
2252    size_type __back_capacity = __back_spare();
2253    if (__n > __back_capacity)
2254        __add_back_capacity(__n - __back_capacity);
2255    // __n <= __back_capacity
2256    for (iterator __i = __base::end(); __n; --__n, ++__i, ++__base::size())
2257        __alloc_traits::construct(__a, _VSTD::addressof(*__i));
2258}
2259
2260template <class _Tp, class _Allocator>
2261void
2262deque<_Tp, _Allocator>::__append(size_type __n, const value_type& __v)
2263{
2264    allocator_type& __a = __base::__alloc();
2265    size_type __back_capacity = __back_spare();
2266    if (__n > __back_capacity)
2267        __add_back_capacity(__n - __back_capacity);
2268    // __n <= __back_capacity
2269    for (iterator __i = __base::end(); __n; --__n, ++__i, ++__base::size())
2270        __alloc_traits::construct(__a, _VSTD::addressof(*__i), __v);
2271}
2272
2273// Create front capacity for one block of elements.
2274// Strong guarantee.  Either do it or don't touch anything.
2275template <class _Tp, class _Allocator>
2276void
2277deque<_Tp, _Allocator>::__add_front_capacity()
2278{
2279    allocator_type& __a = __base::__alloc();
2280    if (__back_spare() >= __base::__block_size)
2281    {
2282        __base::__start_ += __base::__block_size;
2283        pointer __pt = __base::__map_.back();
2284        __base::__map_.pop_back();
2285        __base::__map_.push_front(__pt);
2286    }
2287    // Else if __base::__map_.size() < __base::__map_.capacity() then we need to allocate 1 buffer
2288    else if (__base::__map_.size() < __base::__map_.capacity())
2289    {   // we can put the new buffer into the map, but don't shift things around
2290        // until all buffers are allocated.  If we throw, we don't need to fix
2291        // anything up (any added buffers are undetectible)
2292        if (__base::__map_.__front_spare() > 0)
2293            __base::__map_.push_front(__alloc_traits::allocate(__a, __base::__block_size));
2294        else
2295        {
2296            __base::__map_.push_back(__alloc_traits::allocate(__a, __base::__block_size));
2297            // Done allocating, reorder capacity
2298            pointer __pt = __base::__map_.back();
2299            __base::__map_.pop_back();
2300            __base::__map_.push_front(__pt);
2301        }
2302        __base::__start_ = __base::__map_.size() == 1 ?
2303                               __base::__block_size / 2 :
2304                               __base::__start_ + __base::__block_size;
2305    }
2306    // Else need to allocate 1 buffer, *and* we need to reallocate __map_.
2307    else
2308    {
2309        __split_buffer<pointer, typename __base::__pointer_allocator&>
2310            __buf(max<size_type>(2 * __base::__map_.capacity(), 1),
2311                  0, __base::__map_.__alloc());
2312
2313        typedef __allocator_destructor<_Allocator> _Dp;
2314        unique_ptr<pointer, _Dp> __hold(
2315            __alloc_traits::allocate(__a, __base::__block_size),
2316                _Dp(__a, __base::__block_size));
2317        __buf.push_back(__hold.get());
2318        __hold.release();
2319
2320        for (typename __base::__map_pointer __i = __base::__map_.begin();
2321                __i != __base::__map_.end(); ++__i)
2322            __buf.push_back(*__i);
2323        _VSTD::swap(__base::__map_.__first_, __buf.__first_);
2324        _VSTD::swap(__base::__map_.__begin_, __buf.__begin_);
2325        _VSTD::swap(__base::__map_.__end_, __buf.__end_);
2326        _VSTD::swap(__base::__map_.__end_cap(), __buf.__end_cap());
2327        __base::__start_ = __base::__map_.size() == 1 ?
2328                               __base::__block_size / 2 :
2329                               __base::__start_ + __base::__block_size;
2330    }
2331}
2332
2333// Create front capacity for __n elements.
2334// Strong guarantee.  Either do it or don't touch anything.
2335template <class _Tp, class _Allocator>
2336void
2337deque<_Tp, _Allocator>::__add_front_capacity(size_type __n)
2338{
2339    allocator_type& __a = __base::__alloc();
2340    size_type __nb = __recommend_blocks(__n + __base::__map_.empty());
2341    // Number of unused blocks at back:
2342    size_type __back_capacity = __back_spare() / __base::__block_size;
2343    __back_capacity = _VSTD::min(__back_capacity, __nb);  // don't take more than you need
2344    __nb -= __back_capacity;  // number of blocks need to allocate
2345    // If __nb == 0, then we have sufficient capacity.
2346    if (__nb == 0)
2347    {
2348        __base::__start_ += __base::__block_size * __back_capacity;
2349        for (; __back_capacity > 0; --__back_capacity)
2350        {
2351            pointer __pt = __base::__map_.back();
2352            __base::__map_.pop_back();
2353            __base::__map_.push_front(__pt);
2354        }
2355    }
2356    // Else if __nb <= __map_.capacity() - __map_.size() then we need to allocate __nb buffers
2357    else if (__nb <= __base::__map_.capacity() - __base::__map_.size())
2358    {   // we can put the new buffers into the map, but don't shift things around
2359        // until all buffers are allocated.  If we throw, we don't need to fix
2360        // anything up (any added buffers are undetectible)
2361        for (; __nb > 0; --__nb, __base::__start_ += __base::__block_size - (__base::__map_.size() == 1))
2362        {
2363            if (__base::__map_.__front_spare() == 0)
2364                break;
2365            __base::__map_.push_front(__alloc_traits::allocate(__a, __base::__block_size));
2366        }
2367        for (; __nb > 0; --__nb, ++__back_capacity)
2368            __base::__map_.push_back(__alloc_traits::allocate(__a, __base::__block_size));
2369        // Done allocating, reorder capacity
2370        __base::__start_ += __back_capacity * __base::__block_size;
2371        for (; __back_capacity > 0; --__back_capacity)
2372        {
2373            pointer __pt = __base::__map_.back();
2374            __base::__map_.pop_back();
2375            __base::__map_.push_front(__pt);
2376        }
2377    }
2378    // Else need to allocate __nb buffers, *and* we need to reallocate __map_.
2379    else
2380    {
2381        size_type __ds = (__nb + __back_capacity) * __base::__block_size - __base::__map_.empty();
2382        __split_buffer<pointer, typename __base::__pointer_allocator&>
2383            __buf(max<size_type>(2* __base::__map_.capacity(),
2384                                 __nb + __base::__map_.size()),
2385                  0, __base::__map_.__alloc());
2386#ifndef _LIBCPP_NO_EXCEPTIONS
2387        try
2388        {
2389#endif  // _LIBCPP_NO_EXCEPTIONS
2390            for (; __nb > 0; --__nb)
2391                __buf.push_back(__alloc_traits::allocate(__a, __base::__block_size));
2392#ifndef _LIBCPP_NO_EXCEPTIONS
2393        }
2394        catch (...)
2395        {
2396            for (typename __base::__map_pointer __i = __buf.begin();
2397                    __i != __buf.end(); ++__i)
2398                __alloc_traits::deallocate(__a, *__i, __base::__block_size);
2399            throw;
2400        }
2401#endif  // _LIBCPP_NO_EXCEPTIONS
2402        for (; __back_capacity > 0; --__back_capacity)
2403        {
2404            __buf.push_back(__base::__map_.back());
2405            __base::__map_.pop_back();
2406        }
2407        for (typename __base::__map_pointer __i = __base::__map_.begin();
2408                __i != __base::__map_.end(); ++__i)
2409            __buf.push_back(*__i);
2410        _VSTD::swap(__base::__map_.__first_, __buf.__first_);
2411        _VSTD::swap(__base::__map_.__begin_, __buf.__begin_);
2412        _VSTD::swap(__base::__map_.__end_, __buf.__end_);
2413        _VSTD::swap(__base::__map_.__end_cap(), __buf.__end_cap());
2414        __base::__start_ += __ds;
2415    }
2416}
2417
2418// Create back capacity for one block of elements.
2419// Strong guarantee.  Either do it or don't touch anything.
2420template <class _Tp, class _Allocator>
2421void
2422deque<_Tp, _Allocator>::__add_back_capacity()
2423{
2424    allocator_type& __a = __base::__alloc();
2425    if (__front_spare() >= __base::__block_size)
2426    {
2427        __base::__start_ -= __base::__block_size;
2428        pointer __pt = __base::__map_.front();
2429        __base::__map_.pop_front();
2430        __base::__map_.push_back(__pt);
2431    }
2432    // Else if __nb <= __map_.capacity() - __map_.size() then we need to allocate __nb buffers
2433    else if (__base::__map_.size() < __base::__map_.capacity())
2434    {   // we can put the new buffer into the map, but don't shift things around
2435        // until it is allocated.  If we throw, we don't need to fix
2436        // anything up (any added buffers are undetectible)
2437        if (__base::__map_.__back_spare() != 0)
2438            __base::__map_.push_back(__alloc_traits::allocate(__a, __base::__block_size));
2439        else
2440        {
2441            __base::__map_.push_front(__alloc_traits::allocate(__a, __base::__block_size));
2442            // Done allocating, reorder capacity
2443            pointer __pt = __base::__map_.front();
2444            __base::__map_.pop_front();
2445            __base::__map_.push_back(__pt);
2446        }
2447    }
2448    // Else need to allocate 1 buffer, *and* we need to reallocate __map_.
2449    else
2450    {
2451        __split_buffer<pointer, typename __base::__pointer_allocator&>
2452            __buf(max<size_type>(2* __base::__map_.capacity(), 1),
2453                  __base::__map_.size(),
2454                  __base::__map_.__alloc());
2455
2456        typedef __allocator_destructor<_Allocator> _Dp;
2457        unique_ptr<pointer, _Dp> __hold(
2458            __alloc_traits::allocate(__a, __base::__block_size),
2459                _Dp(__a, __base::__block_size));
2460        __buf.push_back(__hold.get());
2461        __hold.release();
2462
2463        for (typename __base::__map_pointer __i = __base::__map_.end();
2464                __i != __base::__map_.begin();)
2465            __buf.push_front(*--__i);
2466        _VSTD::swap(__base::__map_.__first_, __buf.__first_);
2467        _VSTD::swap(__base::__map_.__begin_, __buf.__begin_);
2468        _VSTD::swap(__base::__map_.__end_, __buf.__end_);
2469        _VSTD::swap(__base::__map_.__end_cap(), __buf.__end_cap());
2470    }
2471}
2472
2473// Create back capacity for __n elements.
2474// Strong guarantee.  Either do it or don't touch anything.
2475template <class _Tp, class _Allocator>
2476void
2477deque<_Tp, _Allocator>::__add_back_capacity(size_type __n)
2478{
2479    allocator_type& __a = __base::__alloc();
2480    size_type __nb = __recommend_blocks(__n + __base::__map_.empty());
2481    // Number of unused blocks at front:
2482    size_type __front_capacity = __front_spare() / __base::__block_size;
2483    __front_capacity = _VSTD::min(__front_capacity, __nb);  // don't take more than you need
2484    __nb -= __front_capacity;  // number of blocks need to allocate
2485    // If __nb == 0, then we have sufficient capacity.
2486    if (__nb == 0)
2487    {
2488        __base::__start_ -= __base::__block_size * __front_capacity;
2489        for (; __front_capacity > 0; --__front_capacity)
2490        {
2491            pointer __pt = __base::__map_.front();
2492            __base::__map_.pop_front();
2493            __base::__map_.push_back(__pt);
2494        }
2495    }
2496    // Else if __nb <= __map_.capacity() - __map_.size() then we need to allocate __nb buffers
2497    else if (__nb <= __base::__map_.capacity() - __base::__map_.size())
2498    {   // we can put the new buffers into the map, but don't shift things around
2499        // until all buffers are allocated.  If we throw, we don't need to fix
2500        // anything up (any added buffers are undetectible)
2501        for (; __nb > 0; --__nb)
2502        {
2503            if (__base::__map_.__back_spare() == 0)
2504                break;
2505            __base::__map_.push_back(__alloc_traits::allocate(__a, __base::__block_size));
2506        }
2507        for (; __nb > 0; --__nb, ++__front_capacity, __base::__start_ +=
2508                                 __base::__block_size - (__base::__map_.size() == 1))
2509            __base::__map_.push_front(__alloc_traits::allocate(__a, __base::__block_size));
2510        // Done allocating, reorder capacity
2511        __base::__start_ -= __base::__block_size * __front_capacity;
2512        for (; __front_capacity > 0; --__front_capacity)
2513        {
2514            pointer __pt = __base::__map_.front();
2515            __base::__map_.pop_front();
2516            __base::__map_.push_back(__pt);
2517        }
2518    }
2519    // Else need to allocate __nb buffers, *and* we need to reallocate __map_.
2520    else
2521    {
2522        size_type __ds = __front_capacity * __base::__block_size;
2523        __split_buffer<pointer, typename __base::__pointer_allocator&>
2524            __buf(max<size_type>(2* __base::__map_.capacity(),
2525                                 __nb + __base::__map_.size()),
2526                  __base::__map_.size() - __front_capacity,
2527                  __base::__map_.__alloc());
2528#ifndef _LIBCPP_NO_EXCEPTIONS
2529        try
2530        {
2531#endif  // _LIBCPP_NO_EXCEPTIONS
2532            for (; __nb > 0; --__nb)
2533                __buf.push_back(__alloc_traits::allocate(__a, __base::__block_size));
2534#ifndef _LIBCPP_NO_EXCEPTIONS
2535        }
2536        catch (...)
2537        {
2538            for (typename __base::__map_pointer __i = __buf.begin();
2539                    __i != __buf.end(); ++__i)
2540                __alloc_traits::deallocate(__a, *__i, __base::__block_size);
2541            throw;
2542        }
2543#endif  // _LIBCPP_NO_EXCEPTIONS
2544        for (; __front_capacity > 0; --__front_capacity)
2545        {
2546            __buf.push_back(__base::__map_.front());
2547            __base::__map_.pop_front();
2548        }
2549        for (typename __base::__map_pointer __i = __base::__map_.end();
2550                __i != __base::__map_.begin();)
2551            __buf.push_front(*--__i);
2552        _VSTD::swap(__base::__map_.__first_, __buf.__first_);
2553        _VSTD::swap(__base::__map_.__begin_, __buf.__begin_);
2554        _VSTD::swap(__base::__map_.__end_, __buf.__end_);
2555        _VSTD::swap(__base::__map_.__end_cap(), __buf.__end_cap());
2556        __base::__start_ -= __ds;
2557    }
2558}
2559
2560template <class _Tp, class _Allocator>
2561void
2562deque<_Tp, _Allocator>::pop_front()
2563{
2564    allocator_type& __a = __base::__alloc();
2565    __alloc_traits::destroy(__a, __to_raw_pointer(*(__base::__map_.begin() +
2566                                                    __base::__start_ / __base::__block_size) +
2567                                                    __base::__start_ % __base::__block_size));
2568    --__base::size();
2569    if (++__base::__start_ >= 2 * __base::__block_size)
2570    {
2571        __alloc_traits::deallocate(__a, __base::__map_.front(), __base::__block_size);
2572        __base::__map_.pop_front();
2573        __base::__start_ -= __base::__block_size;
2574    }
2575}
2576
2577template <class _Tp, class _Allocator>
2578void
2579deque<_Tp, _Allocator>::pop_back()
2580{
2581    allocator_type& __a = __base::__alloc();
2582    size_type __p = __base::size() + __base::__start_ - 1;
2583    __alloc_traits::destroy(__a, __to_raw_pointer(*(__base::__map_.begin() +
2584                                                    __p / __base::__block_size) +
2585                                                    __p % __base::__block_size));
2586    --__base::size();
2587    if (__back_spare() >= 2 * __base::__block_size)
2588    {
2589        __alloc_traits::deallocate(__a, __base::__map_.back(), __base::__block_size);
2590        __base::__map_.pop_back();
2591    }
2592}
2593
2594// move assign [__f, __l) to [__r, __r + (__l-__f)).
2595// If __vt points into [__f, __l), then subtract (__f - __r) from __vt.
2596template <class _Tp, class _Allocator>
2597typename deque<_Tp, _Allocator>::iterator
2598deque<_Tp, _Allocator>::__move_and_check(iterator __f, iterator __l, iterator __r,
2599                                         const_pointer& __vt)
2600{
2601    // as if
2602    //   for (; __f != __l; ++__f, ++__r)
2603    //       *__r = _VSTD::move(*__f);
2604    difference_type __n = __l - __f;
2605    while (__n > 0)
2606    {
2607        pointer __fb = __f.__ptr_;
2608        pointer __fe = *__f.__m_iter_ + __base::__block_size;
2609        difference_type __bs = __fe - __fb;
2610        if (__bs > __n)
2611        {
2612            __bs = __n;
2613            __fe = __fb + __bs;
2614        }
2615        if (__fb <= __vt && __vt < __fe)
2616            __vt = (const_iterator(static_cast<__map_const_pointer>(__f.__m_iter_), __vt) -= __f - __r).__ptr_;
2617        __r = _VSTD::move(__fb, __fe, __r);
2618        __n -= __bs;
2619        __f += __bs;
2620    }
2621    return __r;
2622}
2623
2624// move assign [__f, __l) to [__r - (__l-__f), __r) backwards.
2625// If __vt points into [__f, __l), then add (__r - __l) to __vt.
2626template <class _Tp, class _Allocator>
2627typename deque<_Tp, _Allocator>::iterator
2628deque<_Tp, _Allocator>::__move_backward_and_check(iterator __f, iterator __l, iterator __r,
2629                                                  const_pointer& __vt)
2630{
2631    // as if
2632    //   while (__f != __l)
2633    //       *--__r = _VSTD::move(*--__l);
2634    difference_type __n = __l - __f;
2635    while (__n > 0)
2636    {
2637        --__l;
2638        pointer __lb = *__l.__m_iter_;
2639        pointer __le = __l.__ptr_ + 1;
2640        difference_type __bs = __le - __lb;
2641        if (__bs > __n)
2642        {
2643            __bs = __n;
2644            __lb = __le - __bs;
2645        }
2646        if (__lb <= __vt && __vt < __le)
2647            __vt = (const_iterator(static_cast<__map_const_pointer>(__l.__m_iter_), __vt) += __r - __l - 1).__ptr_;
2648        __r = _VSTD::move_backward(__lb, __le, __r);
2649        __n -= __bs;
2650        __l -= __bs - 1;
2651    }
2652    return __r;
2653}
2654
2655// move construct [__f, __l) to [__r, __r + (__l-__f)).
2656// If __vt points into [__f, __l), then add (__r - __f) to __vt.
2657template <class _Tp, class _Allocator>
2658void
2659deque<_Tp, _Allocator>::__move_construct_and_check(iterator __f, iterator __l,
2660                                                   iterator __r, const_pointer& __vt)
2661{
2662    allocator_type& __a = __base::__alloc();
2663    // as if
2664    //   for (; __f != __l; ++__r, ++__f, ++__base::size())
2665    //       __alloc_traits::construct(__a, _VSTD::addressof(*__r), _VSTD::move(*__f));
2666    difference_type __n = __l - __f;
2667    while (__n > 0)
2668    {
2669        pointer __fb = __f.__ptr_;
2670        pointer __fe = *__f.__m_iter_ + __base::__block_size;
2671        difference_type __bs = __fe - __fb;
2672        if (__bs > __n)
2673        {
2674            __bs = __n;
2675            __fe = __fb + __bs;
2676        }
2677        if (__fb <= __vt && __vt < __fe)
2678            __vt = (const_iterator(static_cast<__map_const_pointer>(__f.__m_iter_), __vt) += __r - __f).__ptr_;
2679        for (; __fb != __fe; ++__fb, ++__r, ++__base::size())
2680            __alloc_traits::construct(__a, _VSTD::addressof(*__r), _VSTD::move(*__fb));
2681        __n -= __bs;
2682        __f += __bs;
2683    }
2684}
2685
2686// move construct [__f, __l) to [__r - (__l-__f), __r) backwards.
2687// If __vt points into [__f, __l), then subtract (__l - __r) from __vt.
2688template <class _Tp, class _Allocator>
2689void
2690deque<_Tp, _Allocator>::__move_construct_backward_and_check(iterator __f, iterator __l,
2691                                                            iterator __r, const_pointer& __vt)
2692{
2693    allocator_type& __a = __base::__alloc();
2694    // as if
2695    //   for (iterator __j = __l; __j != __f;)
2696    //   {
2697    //       __alloc_traitsconstruct(__a, _VSTD::addressof(*--__r), _VSTD::move(*--__j));
2698    //       --__base::__start_;
2699    //       ++__base::size();
2700    //   }
2701    difference_type __n = __l - __f;
2702    while (__n > 0)
2703    {
2704        --__l;
2705        pointer __lb = *__l.__m_iter_;
2706        pointer __le = __l.__ptr_ + 1;
2707        difference_type __bs = __le - __lb;
2708        if (__bs > __n)
2709        {
2710            __bs = __n;
2711            __lb = __le - __bs;
2712        }
2713        if (__lb <= __vt && __vt < __le)
2714            __vt = (const_iterator(static_cast<__map_const_pointer>(__l.__m_iter_), __vt) -= __l - __r + 1).__ptr_;
2715        while (__le != __lb)
2716        {
2717            __alloc_traits::construct(__a, _VSTD::addressof(*--__r), _VSTD::move(*--__le));
2718            --__base::__start_;
2719            ++__base::size();
2720        }
2721        __n -= __bs;
2722        __l -= __bs - 1;
2723    }
2724}
2725
2726template <class _Tp, class _Allocator>
2727typename deque<_Tp, _Allocator>::iterator
2728deque<_Tp, _Allocator>::erase(const_iterator __f)
2729{
2730    iterator __b = __base::begin();
2731    difference_type __pos = __f - __b;
2732    iterator __p = __b + __pos;
2733    allocator_type& __a = __base::__alloc();
2734    if (__pos <= (__base::size() - 1) / 2)
2735    {   // erase from front
2736        _VSTD::move_backward(__b, __p, _VSTD::next(__p));
2737        __alloc_traits::destroy(__a, _VSTD::addressof(*__b));
2738        --__base::size();
2739        ++__base::__start_;
2740        if (__front_spare() >= 2 * __base::__block_size)
2741        {
2742            __alloc_traits::deallocate(__a, __base::__map_.front(), __base::__block_size);
2743            __base::__map_.pop_front();
2744            __base::__start_ -= __base::__block_size;
2745        }
2746    }
2747    else
2748    {   // erase from back
2749        iterator __i = _VSTD::move(_VSTD::next(__p), __base::end(), __p);
2750        __alloc_traits::destroy(__a, _VSTD::addressof(*__i));
2751        --__base::size();
2752        if (__back_spare() >= 2 * __base::__block_size)
2753        {
2754            __alloc_traits::deallocate(__a, __base::__map_.back(), __base::__block_size);
2755            __base::__map_.pop_back();
2756        }
2757    }
2758    return __base::begin() + __pos;
2759}
2760
2761template <class _Tp, class _Allocator>
2762typename deque<_Tp, _Allocator>::iterator
2763deque<_Tp, _Allocator>::erase(const_iterator __f, const_iterator __l)
2764{
2765    difference_type __n = __l - __f;
2766    iterator __b = __base::begin();
2767    difference_type __pos = __f - __b;
2768    iterator __p = __b + __pos;
2769    if (__n > 0)
2770    {
2771        allocator_type& __a = __base::__alloc();
2772        if (__pos <= (__base::size() - __n) / 2)
2773        {   // erase from front
2774            iterator __i = _VSTD::move_backward(__b, __p, __p + __n);
2775            for (; __b != __i; ++__b)
2776                __alloc_traits::destroy(__a, _VSTD::addressof(*__b));
2777            __base::size() -= __n;
2778            __base::__start_ += __n;
2779            while (__front_spare() >= 2 * __base::__block_size)
2780            {
2781                __alloc_traits::deallocate(__a, __base::__map_.front(), __base::__block_size);
2782                __base::__map_.pop_front();
2783                __base::__start_ -= __base::__block_size;
2784            }
2785        }
2786        else
2787        {   // erase from back
2788            iterator __i = _VSTD::move(__p + __n, __base::end(), __p);
2789            for (iterator __e = __base::end(); __i != __e; ++__i)
2790                __alloc_traits::destroy(__a, _VSTD::addressof(*__i));
2791            __base::size() -= __n;
2792            while (__back_spare() >= 2 * __base::__block_size)
2793            {
2794                __alloc_traits::deallocate(__a, __base::__map_.back(), __base::__block_size);
2795                __base::__map_.pop_back();
2796            }
2797        }
2798    }
2799    return __base::begin() + __pos;
2800}
2801
2802template <class _Tp, class _Allocator>
2803void
2804deque<_Tp, _Allocator>::__erase_to_end(const_iterator __f)
2805{
2806    iterator __e = __base::end();
2807    difference_type __n = __e - __f;
2808    if (__n > 0)
2809    {
2810        allocator_type& __a = __base::__alloc();
2811        iterator __b = __base::begin();
2812        difference_type __pos = __f - __b;
2813        for (iterator __p = __b + __pos; __p != __e; ++__p)
2814            __alloc_traits::destroy(__a, _VSTD::addressof(*__p));
2815        __base::size() -= __n;
2816        while (__back_spare() >= 2 * __base::__block_size)
2817        {
2818            __alloc_traits::deallocate(__a, __base::__map_.back(), __base::__block_size);
2819            __base::__map_.pop_back();
2820        }
2821    }
2822}
2823
2824template <class _Tp, class _Allocator>
2825inline
2826void
2827deque<_Tp, _Allocator>::swap(deque& __c)
2828#if _LIBCPP_STD_VER >= 14
2829        _NOEXCEPT
2830#else
2831        _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
2832                    __is_nothrow_swappable<allocator_type>::value)
2833#endif
2834{
2835    __base::swap(__c);
2836}
2837
2838template <class _Tp, class _Allocator>
2839inline
2840void
2841deque<_Tp, _Allocator>::clear() _NOEXCEPT
2842{
2843    __base::clear();
2844}
2845
2846template <class _Tp, class _Allocator>
2847inline _LIBCPP_INLINE_VISIBILITY
2848bool
2849operator==(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2850{
2851    const typename deque<_Tp, _Allocator>::size_type __sz = __x.size();
2852    return __sz == __y.size() && _VSTD::equal(__x.begin(), __x.end(), __y.begin());
2853}
2854
2855template <class _Tp, class _Allocator>
2856inline _LIBCPP_INLINE_VISIBILITY
2857bool
2858operator!=(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2859{
2860    return !(__x == __y);
2861}
2862
2863template <class _Tp, class _Allocator>
2864inline _LIBCPP_INLINE_VISIBILITY
2865bool
2866operator< (const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2867{
2868    return _VSTD::lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end());
2869}
2870
2871template <class _Tp, class _Allocator>
2872inline _LIBCPP_INLINE_VISIBILITY
2873bool
2874operator> (const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2875{
2876    return __y < __x;
2877}
2878
2879template <class _Tp, class _Allocator>
2880inline _LIBCPP_INLINE_VISIBILITY
2881bool
2882operator>=(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2883{
2884    return !(__x < __y);
2885}
2886
2887template <class _Tp, class _Allocator>
2888inline _LIBCPP_INLINE_VISIBILITY
2889bool
2890operator<=(const deque<_Tp, _Allocator>& __x, const deque<_Tp, _Allocator>& __y)
2891{
2892    return !(__y < __x);
2893}
2894
2895template <class _Tp, class _Allocator>
2896inline _LIBCPP_INLINE_VISIBILITY
2897void
2898swap(deque<_Tp, _Allocator>& __x, deque<_Tp, _Allocator>& __y)
2899    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
2900{
2901    __x.swap(__y);
2902}
2903
2904_LIBCPP_END_NAMESPACE_STD
2905
2906#endif  // _LIBCPP_DEQUE
2907