/storage/packages/gcc/5.3.0/include/c++/5.3.0/bits/stl_vector.h

// Vector implementation -*- C++ -*-

// Copyright (C) 2001-2015 Free Software Foundation, Inc.

//

// This file is part of the GNU ISO C++ Library.  This library is free

// software; you can redistribute it and/or modify it under the

// terms of the GNU General Public License as published by the

// Free Software Foundation; either version 3, or (at your option)

// any later version.

// This library is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional

// permissions described in the GCC Runtime Library Exception, version

// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and

// a copy of the GCC Runtime Library Exception along with this program;

// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see

// <http://www.gnu.org/licenses/>.

/*

 *

 * Copyright (c) 1994

 * Hewlett-Packard Company

 *

 * Permission to use, copy, modify, distribute and sell this software

 * and its documentation for any purpose is hereby granted without fee,

 * provided that the above copyright notice appear in all copies and

 * that both that copyright notice and this permission notice appear

 * in supporting documentation.  Hewlett-Packard Company makes no

 * representations about the suitability of this software for any

 * purpose.  It is provided "as is" without express or implied warranty.

 *

 *

 * Copyright (c) 1996

 * Silicon Graphics Computer Systems, Inc.

 *

 * Permission to use, copy, modify, distribute and sell this software

 * and its documentation for any purpose is hereby granted without fee,

 * provided that the above copyright notice appear in all copies and

 * that both that copyright notice and this permission notice appear

 * in supporting documentation.  Silicon Graphics makes no

 * representations about the suitability of this  software for any

 * purpose.  It is provided "as is" without express or implied warranty.

 */

/** @file bits/stl_vector.h

 *  This is an internal header file, included by other library headers.

 *  Do not attempt to use it directly. @headername{vector}

 */

#ifndef _STL_VECTOR_H

#define _STL_VECTOR_H 1

#include <bits/stl_iterator_base_funcs.h>

#include <bits/functexcept.h>

#include <bits/concept_check.h>

#if __cplusplus >= 201103L

#include <initializer_list>

#endif

namespace std _GLIBCXX_VISIBILITY(default)

{

_GLIBCXX_BEGIN_NAMESPACE_CONTAINER

  /// See bits/stl_deque.h's _Deque_base for an explanation.

  template<typename _Tp, typename _Alloc>

    struct _Vector_base

    {

      typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template

        rebind<_Tp>::other _Tp_alloc_type;

      typedef typename __gnu_cxx::__alloc_traits<_Tp_alloc_type>::pointer

       	pointer;

      struct _Vector_impl 

      : public _Tp_alloc_type

      {

	pointer _M_start;

	pointer _M_finish;

	pointer _M_end_of_storage;

	_Vector_impl()

	: _Tp_alloc_type(), _M_start(), _M_finish(), _M_end_of_storage()

	{ }

	_Vector_impl(_Tp_alloc_type const& __a) _GLIBCXX_NOEXCEPT

	: _Tp_alloc_type(__a), _M_start(), _M_finish(), _M_end_of_storage()

	{ }

#if __cplusplus >= 201103L

	_Vector_impl(_Tp_alloc_type&& __a) noexcept

	: _Tp_alloc_type(std::move(__a)),

	  _M_start(), _M_finish(), _M_end_of_storage()

	{ }

#endif

	void _M_swap_data(_Vector_impl& __x) _GLIBCXX_NOEXCEPT

	{

	  std::swap(_M_start, __x._M_start);

	  std::swap(_M_finish, __x._M_finish);

	  std::swap(_M_end_of_storage, __x._M_end_of_storage);

	}

      };

    public:

      typedef _Alloc allocator_type;

      _Tp_alloc_type&

      _M_get_Tp_allocator() _GLIBCXX_NOEXCEPT

      { return *static_cast<_Tp_alloc_type*>(&this->_M_impl); }

      const _Tp_alloc_type&

      _M_get_Tp_allocator() const _GLIBCXX_NOEXCEPT

      { return *static_cast<const _Tp_alloc_type*>(&this->_M_impl); }

      allocator_type

      get_allocator() const _GLIBCXX_NOEXCEPT

      { return allocator_type(_M_get_Tp_allocator()); }

      _Vector_base()

      : _M_impl() { }

      _Vector_base(const allocator_type& __a) _GLIBCXX_NOEXCEPT

      : _M_impl(__a) { }

      _Vector_base(size_t __n)

      : _M_impl()

      { _M_create_storage(__n); }

      _Vector_base(size_t __n, const allocator_type& __a)

      : _M_impl(__a)

      { _M_create_storage(__n); }

#if __cplusplus >= 201103L

      _Vector_base(_Tp_alloc_type&& __a) noexcept

      : _M_impl(std::move(__a)) { }

      _Vector_base(_Vector_base&& __x) noexcept

      : _M_impl(std::move(__x._M_get_Tp_allocator()))

      { this->_M_impl._M_swap_data(__x._M_impl); }

      _Vector_base(_Vector_base&& __x, const allocator_type& __a)

      : _M_impl(__a)

      {

	if (__x.get_allocator() == __a)

	  this->_M_impl._M_swap_data(__x._M_impl);

	else

	  {

	    size_t __n = __x._M_impl._M_finish - __x._M_impl._M_start;

	    _M_create_storage(__n);

	  }

      }

#endif

      ~_Vector_base() _GLIBCXX_NOEXCEPT

      { _M_deallocate(this->_M_impl._M_start, this->_M_impl._M_end_of_storage

		      - this->_M_impl._M_start); }

    public:

      _Vector_impl _M_impl;

      pointer

      _M_allocate(size_t __n)

      {

	typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Tr;

	return __n != 0 ? _Tr::allocate(_M_impl, __n) : pointer();

      }

      void

      _M_deallocate(pointer __p, size_t __n)

      {

	typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Tr;

	if (__p)

	  _Tr::deallocate(_M_impl, __p, __n);

      }

    private:

      void

      _M_create_storage(size_t __n)

      {

	this->_M_impl._M_start = this->_M_allocate(__n);

	this->_M_impl._M_finish = this->_M_impl._M_start;

	this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __n;

      }

    };

  /**

   *  @brief A standard container which offers fixed time access to

   *  individual elements in any order.

   *

   *  @ingroup sequences

   *

   *  @tparam _Tp  Type of element.

   *  @tparam _Alloc  Allocator type, defaults to allocator<_Tp>.

   *

   *  Meets the requirements of a <a href="tables.html#65">container</a>, a

   *  <a href="tables.html#66">reversible container</a>, and a

   *  <a href="tables.html#67">sequence</a>, including the

   *  <a href="tables.html#68">optional sequence requirements</a> with the

   *  %exception of @c push_front and @c pop_front.

   *

   *  In some terminology a %vector can be described as a dynamic

   *  C-style array, it offers fast and efficient access to individual

   *  elements in any order and saves the user from worrying about

   *  memory and size allocation.  Subscripting ( @c [] ) access is

   *  also provided as with C-style arrays.

  */

  template<typename _Tp, typename _Alloc = std::allocator<_Tp> >

    class vector : protected _Vector_base<_Tp, _Alloc>

    {

      // Concept requirements.

      typedef typename _Alloc::value_type                _Alloc_value_type;

      __glibcxx_class_requires(_Tp, _SGIAssignableConcept)

      __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept)

      typedef _Vector_base<_Tp, _Alloc>			 _Base;

      typedef typename _Base::_Tp_alloc_type		 _Tp_alloc_type;

      typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type>  _Alloc_traits;

    public:

      typedef _Tp					 value_type;

      typedef typename _Base::pointer                    pointer;

      typedef typename _Alloc_traits::const_pointer      const_pointer;

      typedef typename _Alloc_traits::reference          reference;

      typedef typename _Alloc_traits::const_reference    const_reference;

      typedef __gnu_cxx::__normal_iterator<pointer, vector> iterator;

      typedef __gnu_cxx::__normal_iterator<const_pointer, vector>

      const_iterator;

      typedef std::reverse_iterator<const_iterator>  const_reverse_iterator;

      typedef std::reverse_iterator<iterator>		 reverse_iterator;

      typedef size_t					 size_type;

      typedef ptrdiff_t					 difference_type;

      typedef _Alloc                        		 allocator_type;

    protected:

      using _Base::_M_allocate;

      using _Base::_M_deallocate;

      using _Base::_M_impl;

      using _Base::_M_get_Tp_allocator;

    public:

      // [23.2.4.1] construct/copy/destroy

      // (assign() and get_allocator() are also listed in this section)

      /**

       *  @brief  Creates a %vector with no elements.

       */

      vector()

#if __cplusplus >= 201103L

      noexcept(is_nothrow_default_constructible<_Alloc>::value)

#endif

      : _Base() { }

      /**

       *  @brief  Creates a %vector with no elements.

       *  @param  __a  An allocator object.

       */

      explicit

      vector(const allocator_type& __a) _GLIBCXX_NOEXCEPT

      : _Base(__a) { }

#if __cplusplus >= 201103L

      /**

       *  @brief  Creates a %vector with default constructed elements.

       *  @param  __n  The number of elements to initially create.

       *  @param  __a  An allocator.

       *

       *  This constructor fills the %vector with @a __n default

       *  constructed elements.

       */

      explicit

      vector(size_type __n, const allocator_type& __a = allocator_type())

      : _Base(__n, __a)

      { _M_default_initialize(__n); }

      /**

       *  @brief  Creates a %vector with copies of an exemplar element.

       *  @param  __n  The number of elements to initially create.

       *  @param  __value  An element to copy.

       *  @param  __a  An allocator.

       *

       *  This constructor fills the %vector with @a __n copies of @a __value.

       */

      vector(size_type __n, const value_type& __value,

	     const allocator_type& __a = allocator_type())

      : _Base(__n, __a)

      { _M_fill_initialize(__n, __value); }

#else

      /**

       *  @brief  Creates a %vector with copies of an exemplar element.

       *  @param  __n  The number of elements to initially create.

       *  @param  __value  An element to copy.

       *  @param  __a  An allocator.

       *

       *  This constructor fills the %vector with @a __n copies of @a __value.

       */

      explicit

      vector(size_type __n, const value_type& __value = value_type(),

	     const allocator_type& __a = allocator_type())

      : _Base(__n, __a)

      { _M_fill_initialize(__n, __value); }

#endif

      /**

       *  @brief  %Vector copy constructor.

       *  @param  __x  A %vector of identical element and allocator types.

       *

       *  The newly-created %vector uses a copy of the allocation

       *  object used by @a __x.  All the elements of @a __x are copied,

       *  but any extra memory in

       *  @a __x (for fast expansion) will not be copied.

       */

      vector(const vector& __x)

      : _Base(__x.size(),

        _Alloc_traits::_S_select_on_copy(__x._M_get_Tp_allocator()))

      { this->_M_impl._M_finish =

	  std::__uninitialized_copy_a(__x.begin(), __x.end(),

				      this->_M_impl._M_start,

				      _M_get_Tp_allocator());

      }

#if __cplusplus >= 201103L

      /**

       *  @brief  %Vector move constructor.

       *  @param  __x  A %vector of identical element and allocator types.

       *

       *  The newly-created %vector contains the exact contents of @a __x.

       *  The contents of @a __x are a valid, but unspecified %vector.

       */

      vector(vector&& __x) noexcept

      : _Base(std::move(__x)) { }

      /// Copy constructor with alternative allocator

      vector(const vector& __x, const allocator_type& __a)

      : _Base(__x.size(), __a)

      { this->_M_impl._M_finish =

	  std::__uninitialized_copy_a(__x.begin(), __x.end(),

				      this->_M_impl._M_start,

				      _M_get_Tp_allocator());

      }

      /// Move constructor with alternative allocator

      vector(vector&& __rv, const allocator_type& __m)

      noexcept(_Alloc_traits::_S_always_equal())

      : _Base(std::move(__rv), __m)

      {

	if (__rv.get_allocator() != __m)

	  {

	    this->_M_impl._M_finish =

	      std::__uninitialized_move_a(__rv.begin(), __rv.end(),

					  this->_M_impl._M_start,

					  _M_get_Tp_allocator());

	    __rv.clear();

	  }

      }

      /**

       *  @brief  Builds a %vector from an initializer list.

       *  @param  __l  An initializer_list.

       *  @param  __a  An allocator.

       *

       *  Create a %vector consisting of copies of the elements in the

       *  initializer_list @a __l.

       *

       *  This will call the element type's copy constructor N times

       *  (where N is @a __l.size()) and do no memory reallocation.

       */

      vector(initializer_list<value_type> __l,

	     const allocator_type& __a = allocator_type())

      : _Base(__a)

      {

	_M_range_initialize(__l.begin(), __l.end(),

			    random_access_iterator_tag());

      }

#endif

      /**

       *  @brief  Builds a %vector from a range.

       *  @param  __first  An input iterator.

       *  @param  __last  An input iterator.

       *  @param  __a  An allocator.

       *

       *  Create a %vector consisting of copies of the elements from

       *  [first,last).

       *

       *  If the iterators are forward, bidirectional, or

       *  random-access, then this will call the elements' copy

       *  constructor N times (where N is distance(first,last)) and do

       *  no memory reallocation.  But if only input iterators are

       *  used, then this will do at most 2N calls to the copy

       *  constructor, and logN memory reallocations.

       */

#if __cplusplus >= 201103L

      template<typename _InputIterator,

	       typename = std::_RequireInputIter<_InputIterator>>

        vector(_InputIterator __first, _InputIterator __last,

	       const allocator_type& __a = allocator_type())

	: _Base(__a)

        { _M_initialize_dispatch(__first, __last, __false_type()); }

#else

      template<typename _InputIterator>

        vector(_InputIterator __first, _InputIterator __last,

	       const allocator_type& __a = allocator_type())

	: _Base(__a)

        {

	  // Check whether it's an integral type.  If so, it's not an iterator.

	  typedef typename std::__is_integer<_InputIterator>::__type _Integral;

	  _M_initialize_dispatch(__first, __last, _Integral());

	}

#endif

      /**

       *  The dtor only erases the elements, and note that if the

       *  elements themselves are pointers, the pointed-to memory is

       *  not touched in any way.  Managing the pointer is the user's

       *  responsibility.

       */

      ~vector() _GLIBCXX_NOEXCEPT

      { std::_Destroy(this->_M_impl._M_start, this->_M_impl._M_finish,

		      _M_get_Tp_allocator()); }

      /**

       *  @brief  %Vector assignment operator.

       *  @param  __x  A %vector of identical element and allocator types.

       *

       *  All the elements of @a __x are copied, but any extra memory in

       *  @a __x (for fast expansion) will not be copied.  Unlike the

       *  copy constructor, the allocator object is not copied.

       */

      vector&

      operator=(const vector& __x);

#if __cplusplus >= 201103L

      /**

       *  @brief  %Vector move assignment operator.

       *  @param  __x  A %vector of identical element and allocator types.

       *

       *  The contents of @a __x are moved into this %vector (without copying,

       *  if the allocators permit it).

       *  @a __x is a valid, but unspecified %vector.

       */

      vector&

      operator=(vector&& __x) noexcept(_Alloc_traits::_S_nothrow_move())

      {

        constexpr bool __move_storage =

          _Alloc_traits::_S_propagate_on_move_assign()

          || _Alloc_traits::_S_always_equal();

        _M_move_assign(std::move(__x),

                       integral_constant<bool, __move_storage>());

	return *this;

      }

      /**

       *  @brief  %Vector list assignment operator.

       *  @param  __l  An initializer_list.

       *

       *  This function fills a %vector with copies of the elements in the

       *  initializer list @a __l.

       *

       *  Note that the assignment completely changes the %vector and

       *  that the resulting %vector's size is the same as the number

       *  of elements assigned.  Old data may be lost.

       */

      vector&

      operator=(initializer_list<value_type> __l)

      {

	this->assign(__l.begin(), __l.end());

	return *this;

      }

#endif

      /**

       *  @brief  Assigns a given value to a %vector.

       *  @param  __n  Number of elements to be assigned.

       *  @param  __val  Value to be assigned.

       *

       *  This function fills a %vector with @a __n copies of the given

       *  value.  Note that the assignment completely changes the

       *  %vector and that the resulting %vector's size is the same as

       *  the number of elements assigned.  Old data may be lost.

       */

      void

      assign(size_type __n, const value_type& __val)

      { _M_fill_assign(__n, __val); }

      /**

       *  @brief  Assigns a range to a %vector.

       *  @param  __first  An input iterator.

       *  @param  __last   An input iterator.

       *

       *  This function fills a %vector with copies of the elements in the

       *  range [__first,__last).

       *

       *  Note that the assignment completely changes the %vector and

       *  that the resulting %vector's size is the same as the number

       *  of elements assigned.  Old data may be lost.

       */

#if __cplusplus >= 201103L

      template<typename _InputIterator,

	       typename = std::_RequireInputIter<_InputIterator>>

        void

        assign(_InputIterator __first, _InputIterator __last)

        { _M_assign_dispatch(__first, __last, __false_type()); }

#else

      template<typename _InputIterator>

        void

        assign(_InputIterator __first, _InputIterator __last)

        {

	  // Check whether it's an integral type.  If so, it's not an iterator.

	  typedef typename std::__is_integer<_InputIterator>::__type _Integral;

	  _M_assign_dispatch(__first, __last, _Integral());

	}

#endif

#if __cplusplus >= 201103L

      /**

       *  @brief  Assigns an initializer list to a %vector.

       *  @param  __l  An initializer_list.

       *

       *  This function fills a %vector with copies of the elements in the

       *  initializer list @a __l.

       *

       *  Note that the assignment completely changes the %vector and

       *  that the resulting %vector's size is the same as the number

       *  of elements assigned.  Old data may be lost.

       */

      void

      assign(initializer_list<value_type> __l)

      { this->assign(__l.begin(), __l.end()); }

#endif

      /// Get a copy of the memory allocation object.

      using _Base::get_allocator;

      // iterators

      /**

       *  Returns a read/write iterator that points to the first

       *  element in the %vector.  Iteration is done in ordinary

       *  element order.

       */

      iterator

      begin() _GLIBCXX_NOEXCEPT

      { return iterator(this->_M_impl._M_start); }

      /**

       *  Returns a read-only (constant) iterator that points to the

       *  first element in the %vector.  Iteration is done in ordinary

       *  element order.

       */

      const_iterator

      begin() const _GLIBCXX_NOEXCEPT

      { return const_iterator(this->_M_impl._M_start); }

      /**

       *  Returns a read/write iterator that points one past the last

       *  element in the %vector.  Iteration is done in ordinary

       *  element order.

       */

      iterator

      end() _GLIBCXX_NOEXCEPT

      { return iterator(this->_M_impl._M_finish); }

      /**

       *  Returns a read-only (constant) iterator that points one past

       *  the last element in the %vector.  Iteration is done in

       *  ordinary element order.

       */

      const_iterator

      end() const _GLIBCXX_NOEXCEPT

      { return const_iterator(this->_M_impl._M_finish); }

      /**

       *  Returns a read/write reverse iterator that points to the

       *  last element in the %vector.  Iteration is done in reverse

       *  element order.

       */

      reverse_iterator

      rbegin() _GLIBCXX_NOEXCEPT

      { return reverse_iterator(end()); }

      /**

       *  Returns a read-only (constant) reverse iterator that points

       *  to the last element in the %vector.  Iteration is done in

       *  reverse element order.

       */

      const_reverse_iterator

      rbegin() const _GLIBCXX_NOEXCEPT

      { return const_reverse_iterator(end()); }

      /**

       *  Returns a read/write reverse iterator that points to one

       *  before the first element in the %vector.  Iteration is done

       *  in reverse element order.

       */

      reverse_iterator

      rend() _GLIBCXX_NOEXCEPT

      { return reverse_iterator(begin()); }

      /**

       *  Returns a read-only (constant) reverse iterator that points

       *  to one before the first element in the %vector.  Iteration

       *  is done in reverse element order.

       */

      const_reverse_iterator

      rend() const _GLIBCXX_NOEXCEPT

      { return const_reverse_iterator(begin()); }

#if __cplusplus >= 201103L

      /**

       *  Returns a read-only (constant) iterator that points to the

       *  first element in the %vector.  Iteration is done in ordinary

       *  element order.

       */

      const_iterator

      cbegin() const noexcept

      { return const_iterator(this->_M_impl._M_start); }

      /**

       *  Returns a read-only (constant) iterator that points one past

       *  the last element in the %vector.  Iteration is done in

       *  ordinary element order.

       */

      const_iterator

      cend() const noexcept

      { return const_iterator(this->_M_impl._M_finish); }

      /**

       *  Returns a read-only (constant) reverse iterator that points

       *  to the last element in the %vector.  Iteration is done in

       *  reverse element order.

       */

      const_reverse_iterator

      crbegin() const noexcept

      { return const_reverse_iterator(end()); }

      /**

       *  Returns a read-only (constant) reverse iterator that points

       *  to one before the first element in the %vector.  Iteration

       *  is done in reverse element order.

       */

      const_reverse_iterator

      crend() const noexcept

      { return const_reverse_iterator(begin()); }

#endif

      // [23.2.4.2] capacity

      /**  Returns the number of elements in the %vector.  */

      size_type

      size() const _GLIBCXX_NOEXCEPT

      { return size_type(this->_M_impl._M_finish - this->_M_impl._M_start); }

      /**  Returns the size() of the largest possible %vector.  */

      size_type

      max_size() const _GLIBCXX_NOEXCEPT

      { return _Alloc_traits::max_size(_M_get_Tp_allocator()); }

#if __cplusplus >= 201103L

      /**

       *  @brief  Resizes the %vector to the specified number of elements.

       *  @param  __new_size  Number of elements the %vector should contain.

       *

       *  This function will %resize the %vector to the specified

       *  number of elements.  If the number is smaller than the

       *  %vector's current size the %vector is truncated, otherwise

       *  default constructed elements are appended.

       */

      void

      resize(size_type __new_size)

      {

	if (__new_size > size())

	  _M_default_append(__new_size - size());

	else if (__new_size < size())

	  _M_erase_at_end(this->_M_impl._M_start + __new_size);

      }

      /**

       *  @brief  Resizes the %vector to the specified number of elements.

       *  @param  __new_size  Number of elements the %vector should contain.

       *  @param  __x  Data with which new elements should be populated.

       *

       *  This function will %resize the %vector to the specified

       *  number of elements.  If the number is smaller than the

       *  %vector's current size the %vector is truncated, otherwise

       *  the %vector is extended and new elements are populated with

       *  given data.

       */

      void

      resize(size_type __new_size, const value_type& __x)

      {

	if (__new_size > size())

	  insert(end(), __new_size - size(), __x);

	else if (__new_size < size())

	  _M_erase_at_end(this->_M_impl._M_start + __new_size);

      }

#else

      /**

       *  @brief  Resizes the %vector to the specified number of elements.

       *  @param  __new_size  Number of elements the %vector should contain.

       *  @param  __x  Data with which new elements should be populated.

       *

       *  This function will %resize the %vector to the specified

       *  number of elements.  If the number is smaller than the

       *  %vector's current size the %vector is truncated, otherwise

       *  the %vector is extended and new elements are populated with

       *  given data.

       */

      void

      resize(size_type __new_size, value_type __x = value_type())

      {

	if (__new_size > size())

	  insert(end(), __new_size - size(), __x);

	else if (__new_size < size())

	  _M_erase_at_end(this->_M_impl._M_start + __new_size);

      }

#endif

#if __cplusplus >= 201103L

      /**  A non-binding request to reduce capacity() to size().  */

      void

      shrink_to_fit()

      { _M_shrink_to_fit(); }

#endif

      /**

       *  Returns the total number of elements that the %vector can

       *  hold before needing to allocate more memory.

       */

      size_type

      capacity() const _GLIBCXX_NOEXCEPT

      { return size_type(this->_M_impl._M_end_of_storage

			 - this->_M_impl._M_start); }

      /**

       *  Returns true if the %vector is empty.  (Thus begin() would

       *  equal end().)

       */

      bool

      empty() const _GLIBCXX_NOEXCEPT

      { return begin() == end(); }

      /**

       *  @brief  Attempt to preallocate enough memory for specified number of

       *          elements.

       *  @param  __n  Number of elements required.

       *  @throw  std::length_error  If @a n exceeds @c max_size().

       *

       *  This function attempts to reserve enough memory for the

       *  %vector to hold the specified number of elements.  If the

       *  number requested is more than max_size(), length_error is

       *  thrown.

       *

       *  The advantage of this function is that if optimal code is a

       *  necessity and the user can determine the number of elements

       *  that will be required, the user can reserve the memory in

       *  %advance, and thus prevent a possible reallocation of memory

       *  and copying of %vector data.

       */

      void

      reserve(size_type __n);

      // element access

      /**

       *  @brief  Subscript access to the data contained in the %vector.

       *  @param __n The index of the element for which data should be

       *  accessed.

       *  @return  Read/write reference to data.

       *

       *  This operator allows for easy, array-style, data access.

       *  Note that data access with this operator is unchecked and

       *  out_of_range lookups are not defined. (For checked lookups

       *  see at().)

       */

      reference

      operator[](size_type __n) _GLIBCXX_NOEXCEPT

      { return *(this->_M_impl._M_start + __n); }

      /**

       *  @brief  Subscript access to the data contained in the %vector.

       *  @param __n The index of the element for which data should be

       *  accessed.

       *  @return  Read-only (constant) reference to data.

       *

       *  This operator allows for easy, array-style, data access.

       *  Note that data access with this operator is unchecked and

       *  out_of_range lookups are not defined. (For checked lookups

       *  see at().)

       */

      const_reference

      operator[](size_type __n) const _GLIBCXX_NOEXCEPT

      { return *(this->_M_impl._M_start + __n); }

    protected:

      /// Safety check used only from at().

      void

      _M_range_check(size_type __n) const

      {

	if (__n >= this->size())

	  __throw_out_of_range_fmt(__N("vector::_M_range_check: __n "

				       "(which is %zu) >= this->size() "

				       "(which is %zu)"),

				   __n, this->size());

      }

    public:

      /**

       *  @brief  Provides access to the data contained in the %vector.

       *  @param __n The index of the element for which data should be

       *  accessed.

       *  @return  Read/write reference to data.

       *  @throw  std::out_of_range  If @a __n is an invalid index.

       *

       *  This function provides for safer data access.  The parameter

       *  is first checked that it is in the range of the vector.  The

       *  function throws out_of_range if the check fails.

       */

      reference

      at(size_type __n)

      {

	_M_range_check(__n);

	return (*this)[__n]; 

      }

      /**

       *  @brief  Provides access to the data contained in the %vector.

       *  @param __n The index of the element for which data should be

       *  accessed.

       *  @return  Read-only (constant) reference to data.

       *  @throw  std::out_of_range  If @a __n is an invalid index.

       *

       *  This function provides for safer data access.  The parameter

       *  is first checked that it is in the range of the vector.  The

       *  function throws out_of_range if the check fails.

       */

      const_reference

      at(size_type __n) const

      {

	_M_range_check(__n);

	return (*this)[__n];

      }

      /**

       *  Returns a read/write reference to the data at the first

       *  element of the %vector.

       */

      reference

      front() _GLIBCXX_NOEXCEPT

      { return *begin(); }

      /**

       *  Returns a read-only (constant) reference to the data at the first

       *  element of the %vector.

       */

      const_reference

      front() const _GLIBCXX_NOEXCEPT

      { return *begin(); }

      /**

       *  Returns a read/write reference to the data at the last

       *  element of the %vector.

       */

      reference

      back() _GLIBCXX_NOEXCEPT

      { return *(end() - 1); }

      /**

       *  Returns a read-only (constant) reference to the data at the

       *  last element of the %vector.

       */

      const_reference

      back() const _GLIBCXX_NOEXCEPT

      { return *(end() - 1); }

      // _GLIBCXX_RESOLVE_LIB_DEFECTS

      // DR 464. Suggestion for new member functions in standard containers.

      // data access

      /**

       *   Returns a pointer such that [data(), data() + size()) is a valid

       *   range.  For a non-empty %vector, data() == &front().

       */

#if __cplusplus >= 201103L

      _Tp*

#else

      pointer

#endif

      data() _GLIBCXX_NOEXCEPT

      { return _M_data_ptr(this->_M_impl._M_start); }

#if __cplusplus >= 201103L

      const _Tp*

#else

      const_pointer

#endif

      data() const _GLIBCXX_NOEXCEPT

      { return _M_data_ptr(this->_M_impl._M_start); }

      // [23.2.4.3] modifiers

      /**

       *  @brief  Add data to the end of the %vector.

       *  @param  __x  Data to be added.

       *

       *  This is a typical stack operation.  The function creates an

       *  element at the end of the %vector and assigns the given data

       *  to it.  Due to the nature of a %vector this operation can be

       *  done in constant time if the %vector has preallocated space

       *  available.

       */

      void

      push_back(const value_type& __x)

      {

	if (this->_M_impl._M_finish != this->_M_impl._M_end_of_storage)

	  {

	    _Alloc_traits::construct(this->_M_impl, this->_M_impl._M_finish,

	                             __x);

	    ++this->_M_impl._M_finish;

	  }

	else

#if __cplusplus >= 201103L

	  _M_emplace_back_aux(__x);

#else

	  _M_insert_aux(end(), __x);

#endif

      }

#if __cplusplus >= 201103L

      void

      push_back(value_type&& __x)

      { emplace_back(std::move(__x)); }

      template<typename... _Args>

        void

        emplace_back(_Args&&... __args);

#endif

      /**

       *  @brief  Removes last element.

       *

       *  This is a typical stack operation. It shrinks the %vector by one.

       *

       *  Note that no data is returned, and if the last element's

       *  data is needed, it should be retrieved before pop_back() is

       *  called.

       */

      void

      pop_back() _GLIBCXX_NOEXCEPT

      {

	--this->_M_impl._M_finish;

	_Alloc_traits::destroy(this->_M_impl, this->_M_impl._M_finish);

      }

#if __cplusplus >= 201103L

      /**

       *  @brief  Inserts an object in %vector before specified iterator.

       *  @param  __position  A const_iterator into the %vector.

       *  @param  __args  Arguments.

       *  @return  An iterator that points to the inserted data.

       *

       *  This function will insert an object of type T constructed

       *  with T(std::forward<Args>(args)...) before the specified location.

       *  Note that this kind of operation could be expensive for a %vector

       *  and if it is frequently used the user should consider using

       *  std::list.

       */

      template<typename... _Args>

        iterator

        emplace(const_iterator __position, _Args&&... __args);

      /**

       *  @brief  Inserts given value into %vector before specified iterator.

       *  @param  __position  A const_iterator into the %vector.

       *  @param  __x  Data to be inserted.

       *  @return  An iterator that points to the inserted data.

       *

       *  This function will insert a copy of the given value before

       *  the specified location.  Note that this kind of operation

       *  could be expensive for a %vector and if it is frequently

       *  used the user should consider using std::list.

       */

      iterator

      insert(const_iterator __position, const value_type& __x);

#else

      /**

       *  @brief  Inserts given value into %vector before specified iterator.

       *  @param  __position  An iterator into the %vector.

       *  @param  __x  Data to be inserted.

       *  @return  An iterator that points to the inserted data.

       *

       *  This function will insert a copy of the given value before

       *  the specified location.  Note that this kind of operation

       *  could be expensive for a %vector and if it is frequently

       *  used the user should consider using std::list.

       */

      iterator

      insert(iterator __position, const value_type& __x);

#endif

#if __cplusplus >= 201103L

      /**

       *  @brief  Inserts given rvalue into %vector before specified iterator.

       *  @param  __position  A const_iterator into the %vector.

       *  @param  __x  Data to be inserted.

       *  @return  An iterator that points to the inserted data.

       *

       *  This function will insert a copy of the given rvalue before

       *  the specified location.  Note that this kind of operation

       *  could be expensive for a %vector and if it is frequently

       *  used the user should consider using std::list.

       */

      iterator

      insert(const_iterator __position, value_type&& __x)

      { return emplace(__position, std::move(__x)); }

      /**

       *  @brief  Inserts an initializer_list into the %vector.

       *  @param  __position  An iterator into the %vector.

       *  @param  __l  An initializer_list.

       *

       *  This function will insert copies of the data in the 

       *  initializer_list @a l into the %vector before the location

       *  specified by @a position.

       *

       *  Note that this kind of operation could be expensive for a

       *  %vector and if it is frequently used the user should

       *  consider using std::list.

       */

      iterator

      insert(const_iterator __position, initializer_list<value_type> __l)

      { return this->insert(__position, __l.begin(), __l.end()); }

#endif

#if __cplusplus >= 201103L

      /**

       *  @brief  Inserts a number of copies of given data into the %vector.

       *  @param  __position  A const_iterator into the %vector.

       *  @param  __n  Number of elements to be inserted.

       *  @param  __x  Data to be inserted.

       *  @return  An iterator that points to the inserted data.

       *

       *  This function will insert a specified number of copies of

       *  the given data before the location specified by @a position.

       *

       *  Note that this kind of operation could be expensive for a

       *  %vector and if it is frequently used the user should

       *  consider using std::list.

       */

      iterator

      insert(const_iterator __position, size_type __n, const value_type& __x)

      {

	difference_type __offset = __position - cbegin();

	_M_fill_insert(begin() + __offset, __n, __x);

	return begin() + __offset;

      }

#else

      /**

       *  @brief  Inserts a number of copies of given data into the %vector.

       *  @param  __position  An iterator into the %vector.

       *  @param  __n  Number of elements to be inserted.

       *  @param  __x  Data to be inserted.

       *

       *  This function will insert a specified number of copies of

       *  the given data before the location specified by @a position.

       *

       *  Note that this kind of operation could be expensive for a

       *  %vector and if it is frequently used the user should

       *  consider using std::list.

       */

      void

      insert(iterator __position, size_type __n, const value_type& __x)

      { _M_fill_insert(__position, __n, __x); }

#endif

#if __cplusplus >= 201103L

      /**

       *  @brief  Inserts a range into the %vector.

       *  @param  __position  A const_iterator into the %vector.

       *  @param  __first  An input iterator.

       *  @param  __last   An input iterator.

       *  @return  An iterator that points to the inserted data.

       *

       *  This function will insert copies of the data in the range

       *  [__first,__last) into the %vector before the location specified

       *  by @a pos.

       *

       *  Note that this kind of operation could be expensive for a

       *  %vector and if it is frequently used the user should

       *  consider using std::list.

       */

      template<typename _InputIterator,

	       typename = std::_RequireInputIter<_InputIterator>>

        iterator

        insert(const_iterator __position, _InputIterator __first,

	       _InputIterator __last)

        {

	  difference_type __offset = __position - cbegin();

	  _M_insert_dispatch(begin() + __offset,

			     __first, __last, __false_type());

	  return begin() + __offset;

	}

#else

      /**

       *  @brief  Inserts a range into the %vector.

       *  @param  __position  An iterator into the %vector.

       *  @param  __first  An input iterator.

       *  @param  __last   An input iterator.

       *

       *  This function will insert copies of the data in the range

       *  [__first,__last) into the %vector before the location specified

       *  by @a pos.

       *

       *  Note that this kind of operation could be expensive for a

       *  %vector and if it is frequently used the user should

       *  consider using std::list.

       */

      template<typename _InputIterator>

        void

        insert(iterator __position, _InputIterator __first,

	       _InputIterator __last)

        {

	  // Check whether it's an integral type.  If so, it's not an iterator.

	  typedef typename std::__is_integer<_InputIterator>::__type _Integral;

	  _M_insert_dispatch(__position, __first, __last, _Integral());

	}

#endif

      /**

       *  @brief  Remove element at given position.

       *  @param  __position  Iterator pointing to element to be erased.

       *  @return  An iterator pointing to the next element (or end()).

       *

       *  This function will erase the element at the given position and thus

       *  shorten the %vector by one.

       *

       *  Note This operation could be expensive and if it is

       *  frequently used the user should consider using std::list.

       *  The user is also cautioned that this function only erases

       *  the element, and that if the element is itself a pointer,

       *  the pointed-to memory is not touched in any way.  Managing

       *  the pointer is the user's responsibility.

       */

      iterator

#if __cplusplus >= 201103L

      erase(const_iterator __position)

      { return _M_erase(begin() + (__position - cbegin())); }

#else

      erase(iterator __position)

      { return _M_erase(__position); }

#endif

      /**

       *  @brief  Remove a range of elements.

       *  @param  __first  Iterator pointing to the first element to be erased.

       *  @param  __last  Iterator pointing to one past the last element to be

       *                  erased.

       *  @return  An iterator pointing to the element pointed to by @a __last

       *           prior to erasing (or end()).

       *

       *  This function will erase the elements in the range

       *  [__first,__last) and shorten the %vector accordingly.

       *

       *  Note This operation could be expensive and if it is

       *  frequently used the user should consider using std::list.

       *  The user is also cautioned that this function only erases

       *  the elements, and that if the elements themselves are

       *  pointers, the pointed-to memory is not touched in any way.

       *  Managing the pointer is the user's responsibility.

       */

      iterator

#if __cplusplus >= 201103L

      erase(const_iterator __first, const_iterator __last)

      {

	const auto __beg = begin();

	const auto __cbeg = cbegin();

	return _M_erase(__beg + (__first - __cbeg), __beg + (__last - __cbeg));

      }

#else

      erase(iterator __first, iterator __last)

      { return _M_erase(__first, __last); }

#endif

      /**

       *  @brief  Swaps data with another %vector.

       *  @param  __x  A %vector of the same element and allocator types.

       *

       *  This exchanges the elements between two vectors in constant time.

       *  (Three pointers, so it should be quite fast.)

       *  Note that the global std::swap() function is specialized such that

       *  std::swap(v1,v2) will feed to this function.

       */

      void

      swap(vector& __x)

#if __cplusplus >= 201103L

      noexcept(_Alloc_traits::_S_nothrow_swap())

#endif

      {

	this->_M_impl._M_swap_data(__x._M_impl);

	_Alloc_traits::_S_on_swap(_M_get_Tp_allocator(),

	                          __x._M_get_Tp_allocator());

      }

      /**

       *  Erases all the elements.  Note that this function only erases the

       *  elements, and that if the elements themselves are pointers, the

       *  pointed-to memory is not touched in any way.  Managing the pointer is

       *  the user's responsibility.

       */

      void

      clear() _GLIBCXX_NOEXCEPT

      { _M_erase_at_end(this->_M_impl._M_start); }

    protected:

      /**

       *  Memory expansion handler.  Uses the member allocation function to

       *  obtain @a n bytes of memory, and then copies [first,last) into it.

       */

      template<typename _ForwardIterator>

        pointer

        _M_allocate_and_copy(size_type __n,

			     _ForwardIterator __first, _ForwardIterator __last)

        {

	  pointer __result = this->_M_allocate(__n);

	  __try

	    {

	      std::__uninitialized_copy_a(__first, __last, __result,

					  _M_get_Tp_allocator());

	      return __result;

	    }

	  __catch(...)

	    {

	      _M_deallocate(__result, __n);

	      __throw_exception_again;

	    }

	}

      // Internal constructor functions follow.

      // Called by the range constructor to implement [23.1.1]/9

      // _GLIBCXX_RESOLVE_LIB_DEFECTS

      // 438. Ambiguity in the "do the right thing" clause

      template<typename _Integer>

        void

        _M_initialize_dispatch(_Integer __n, _Integer __value, __true_type)

        {

	  this->_M_impl._M_start = _M_allocate(static_cast<size_type>(__n));

	  this->_M_impl._M_end_of_storage =

	    this->_M_impl._M_start + static_cast<size_type>(__n);

	  _M_fill_initialize(static_cast<size_type>(__n), __value);

	}

      // Called by the range constructor to implement [23.1.1]/9

      template<typename _InputIterator>

        void

        _M_initialize_dispatch(_InputIterator __first, _InputIterator __last,

			       __false_type)

        {

	  typedef typename std::iterator_traits<_InputIterator>::

	    iterator_category _IterCategory;

	  _M_range_initialize(__first, __last, _IterCategory());

	}

      // Called by the second initialize_dispatch above

      template<typename _InputIterator>

        void

        _M_range_initialize(_InputIterator __first,

			    _InputIterator __last, std::input_iterator_tag)

        {

	  for (; __first != __last; ++__first)

#if __cplusplus >= 201103L

	    emplace_back(*__first);

#else

	    push_back(*__first);

#endif

	}

      // Called by the second initialize_dispatch above

      template<typename _ForwardIterator>

        void

        _M_range_initialize(_ForwardIterator __first,

			    _ForwardIterator __last, std::forward_iterator_tag)

        {

	  const size_type __n = std::distance(__first, __last);

	  this->_M_impl._M_start = this->_M_allocate(__n);

	  this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __n;

	  this->_M_impl._M_finish =

	    std::__uninitialized_copy_a(__first, __last,

					this->_M_impl._M_start,

					_M_get_Tp_allocator());

	}

      // Called by the first initialize_dispatch above and by the

      // vector(n,value,a) constructor.

      void

      _M_fill_initialize(size_type __n, const value_type& __value)

      {

	this->_M_impl._M_finish =

	  std::__uninitialized_fill_n_a(this->_M_impl._M_start, __n, __value,

					_M_get_Tp_allocator());

      }

#if __cplusplus >= 201103L

      // Called by the vector(n) constructor.

      void

      _M_default_initialize(size_type __n)

      {

	this->_M_impl._M_finish =

	  std::__uninitialized_default_n_a(this->_M_impl._M_start, __n,

					   _M_get_Tp_allocator());

      }

#endif

      // Internal assign functions follow.  The *_aux functions do the actual

      // assignment work for the range versions.

      // Called by the range assign to implement [23.1.1]/9

      // _GLIBCXX_RESOLVE_LIB_DEFECTS

      // 438. Ambiguity in the "do the right thing" clause

      template<typename _Integer>

        void

        _M_assign_dispatch(_Integer __n, _Integer __val, __true_type)

        { _M_fill_assign(__n, __val); }

      // Called by the range assign to implement [23.1.1]/9

      template<typename _InputIterator>

        void

        _M_assign_dispatch(_InputIterator __first, _InputIterator __last,

			   __false_type)