/*

  * © Portions copyright (c) 2006-2007 Nokia Corporation.  All rights reserved.

  *

  * Copyright (c) 1994

  * Hewlett-Packard Company

  *

  * Copyright (c) 1996,1997

  * Silicon Graphics Computer Systems, Inc.

  *

  * Copyright (c) 1997

  * Moscow Center for SPARC Technology

  *

  * Copyright (c) 1999 

  * Boris Fomitchev

  *

  * This material is provided "as is", with absolutely no warranty expressed

  * or implied. Any use is at your own risk.

  *

  * Permission to use or copy this software for any purpose is hereby granted 

  * without fee, provided the above notices are retained on all copies.

  * Permission to modify the code and to distribute modified code is granted,

  * provided the above notices are retained, and a notice that the code was

  * modified is included with the above copyright notice.

  *

  */

 /* NOTE: This is an internal header file, included by other STL headers.

  *   You should not attempt to use it directly.

  */

 #ifndef _STLP_INTERNAL_DEQUE_H

 #define _STLP_INTERNAL_DEQUE_H

 # ifndef _STLP_INTERNAL_ALGOBASE_H

 #  include <stl/_algobase.h>

 # endif

 # ifndef _STLP_INTERNAL_ALLOC_H

 #  include <stl/_alloc.h>

 # endif

 # ifndef _STLP_INTERNAL_ITERATOR_H

 #  include <stl/_iterator.h>

 # endif

 # ifndef _STLP_INTERNAL_UNINITIALIZED_H

 #  include <stl/_uninitialized.h>

 # endif

 # ifndef _STLP_RANGE_ERRORS_H

 #  include <stl/_range_errors.h>

 # endif

 /* Class invariants:

  *  For any nonsingular iterator i:

  *    i.node is the address of an element in the map array.  The

  *      contents of i.node is a pointer to the beginning of a node.

  *    i.first == *(i.node) 

  *    i.last  == i.first + node_size

  *    i.cur is a pointer in the range [i.first, i.last).  NOTE:

  *      the implication of this is that i.cur is always a dereferenceable

  *      pointer, even if i is a past-the-end iterator.

  *  Start and Finish are always nonsingular iterators.  NOTE: this means

  *    that an empty deque must have one node, and that a deque

  *    with N elements, where N is the buffer size, must have two nodes.

  *  For every node other than start.node and finish.node, every element

  *    in the node is an initialized object.  If start.node == finish.node,

  *    then [start.cur, finish.cur) are initialized objects, and

  *    the elements outside that range are uninitialized storage.  Otherwise,

  *    [start.cur, start.last) and [finish.first, finish.cur) are initialized

  *    objects, and [start.first, start.cur) and [finish.cur, finish.last)

  *    are uninitialized storage.

  *  [map, map + map_size) is a valid, non-empty range.  

  *  [start.node, finish.node] is a valid range contained within 

  *    [map, map + map_size).  

  *  A pointer in the range [map, map + map_size) points to an allocated node

  *    if and only if the pointer is in the range [start.node, finish.node].

  */

 # undef deque

 # define deque __WORKAROUND_DBG_RENAME(deque)

 _STLP_BEGIN_NAMESPACE

 template <class _Tp>

 struct _Deque_iterator_base {

   enum _Constants { 

     _blocksize = _MAX_BYTES, 

     __buffer_size = (sizeof(_Tp) < (size_t)_blocksize ?

    		    ( (size_t)_blocksize / sizeof(_Tp)) : size_t(1))

   };

   typedef random_access_iterator_tag iterator_category;

   typedef _Tp value_type;

   typedef size_t size_type;

   typedef ptrdiff_t difference_type;

   typedef value_type** _Map_pointer;

   typedef _Deque_iterator_base< _Tp > _Self;

   value_type* _M_cur;

   value_type* _M_first;

   value_type* _M_last;

   _Map_pointer _M_node;

   _Deque_iterator_base(value_type* __x, _Map_pointer __y) 

     : _M_cur(__x), _M_first(*__y),

       _M_last(*__y + __buffer_size), _M_node(__y) {}

   _Deque_iterator_base() : _M_cur(0), _M_first(0), _M_last(0), _M_node(0) {}

   difference_type _M_subtract(const _Self& __x) const {

     return difference_type(__buffer_size) * (_M_node - __x._M_node - 1) +

       (_M_cur - _M_first) + (__x._M_last - __x._M_cur);

   }

   void _M_increment() {

     if (++_M_cur == _M_last) {

       _M_set_node(_M_node + 1);

       _M_cur = _M_first;

     }

   }

   void _M_decrement() {

     if (_M_cur == _M_first) {

       _M_set_node(_M_node - 1);

       _M_cur = _M_last;

     }

     --_M_cur;

   }

   void _M_advance(difference_type __n)

   {

     difference_type __offset = __n + (_M_cur - _M_first);

     if (__offset >= 0 && __offset < difference_type(__buffer_size))

       _M_cur += __n;

     else {

       difference_type __node_offset =

         __offset > 0 ? __offset / __buffer_size

                    : -difference_type((-__offset - 1) / __buffer_size) - 1;

       _M_set_node(_M_node + __node_offset);

       _M_cur = _M_first + 

         (__offset - __node_offset * difference_type(__buffer_size));

     }

   }

   void _M_set_node(_Map_pointer __new_node) {

     _M_last = (_M_first = *(_M_node = __new_node)) + difference_type(__buffer_size);

   }

 };

 template <class _Tp, class _Traits>

 struct _Deque_iterator : public _Deque_iterator_base< _Tp> {

   typedef random_access_iterator_tag iterator_category;

   typedef _Tp value_type;

   typedef typename _Traits::reference  reference;

   typedef typename _Traits::pointer    pointer;

   typedef size_t size_type;

   typedef ptrdiff_t difference_type;

   typedef value_type** _Map_pointer;

   typedef _Deque_iterator_base< _Tp > _Base;

   typedef _Deque_iterator<_Tp, _Traits> _Self;

   typedef _Deque_iterator<_Tp, _Nonconst_traits<_Tp> > _Nonconst_self;

   typedef _Deque_iterator<_Tp, _Const_traits<_Tp> > _Const_self;

   _Deque_iterator(value_type* __x, _Map_pointer __y) :

     _Deque_iterator_base<value_type>(__x,__y) {}

   _Deque_iterator() {}

   _Deque_iterator(const _Nonconst_self& __x) : 

     _Deque_iterator_base<value_type>(__x) {}

   reference operator*() const { 

       return *this->_M_cur; 

   }

   _STLP_DEFINE_ARROW_OPERATOR

   difference_type operator-(const _Self& __x) const { return this->_M_subtract(__x); }

   _Self& operator++() { this->_M_increment(); return *this; }

   _Self operator++(int)  {

     _Self __tmp = *this;

     ++*this;

     return __tmp;

   }

   _Self& operator--() { this->_M_decrement(); return *this; }

   _Self operator--(int) {

     _Self __tmp = *this;

     --*this;

     return __tmp;

   }

   _Self& operator+=(difference_type __n) { this->_M_advance(__n); return *this; }

   _Self operator+(difference_type __n) const

   {

     _Self __tmp = *this;

     return __tmp += __n;

   }

   _Self& operator-=(difference_type __n) { return *this += -__n; }

   _Self operator-(difference_type __n) const {

     _Self __tmp = *this;

     return __tmp -= __n;

   }

   reference operator[](difference_type __n) const { return *(*this + __n); }

 };

 template <class _Tp, class _Traits>

 inline _Deque_iterator<_Tp, _Traits> _STLP_CALL

 operator+(ptrdiff_t __n, const _Deque_iterator<_Tp, _Traits>& __x)

 {

    return __x + __n;

 }

 #ifdef _STLP_USE_SEPARATE_RELOPS_NAMESPACE

 template <class _Tp>

 inline bool _STLP_CALL 

 operator==(const _Deque_iterator_base<_Tp >& __x,

 	   const _Deque_iterator_base<_Tp >& __y) { 

     return __x._M_cur == __y._M_cur; 

 }

 template <class _Tp>

 inline bool _STLP_CALL 

 operator < (const _Deque_iterator_base<_Tp >& __x,

 	    const _Deque_iterator_base<_Tp >& __y) { 

   return (__x._M_node == __y._M_node) ? 

     (__x._M_cur < __y._M_cur) : (__x._M_node < __y._M_node);

 }

 template <class _Tp>

 inline bool _STLP_CALL 

 operator!=(const _Deque_iterator_base<_Tp >& __x,

 	   const _Deque_iterator_base<_Tp >& __y) { 

     return __x._M_cur != __y._M_cur; 

 }

 template <class _Tp>

 inline bool _STLP_CALL 

 operator>(const _Deque_iterator_base<_Tp >& __x,

 	  const _Deque_iterator_base<_Tp >& __y) { 

     return __y < __x;

 }

 template <class _Tp>

 inline bool  _STLP_CALL operator>=(const _Deque_iterator_base<_Tp >& __x,

                                    const _Deque_iterator_base<_Tp >& __y) { 

     return !(__x < __y);

 }

 template <class _Tp>

 inline bool  _STLP_CALL operator<=(const _Deque_iterator_base<_Tp >& __x,

                                    const _Deque_iterator_base<_Tp >& __y) { 

     return !(__y < __x);

 }

 # else

 template <class _Tp, class _Traits1, class _Traits2>

 inline bool  _STLP_CALL

 operator==(const _Deque_iterator<_Tp, _Traits1 >& __x,

 	   const _Deque_iterator<_Tp, _Traits2 >& __y) { 

     return __x._M_cur == __y._M_cur; 

 }

 template <class _Tp, class _Traits1, class _Traits2>

 inline bool _STLP_CALL 

 operator < (const _Deque_iterator<_Tp, _Traits1 >& __x,

 	    const _Deque_iterator<_Tp, _Traits2 >& __y) { 

   return (__x._M_node == __y._M_node) ? 

     (__x._M_cur < __y._M_cur) : (__x._M_node < __y._M_node);

 }

 template <class _Tp>

 inline bool _STLP_CALL 

 operator!=(const _Deque_iterator<_Tp, _Nonconst_traits<_Tp> >& __x,

 	   const _Deque_iterator<_Tp, _Const_traits<_Tp> >& __y) { 

     return __x._M_cur != __y._M_cur; 

 }

 template <class _Tp>

 inline bool _STLP_CALL 

 operator>(const _Deque_iterator<_Tp, _Nonconst_traits<_Tp> >& __x,

 	  const _Deque_iterator<_Tp, _Const_traits<_Tp> >& __y) { 

     return __y < __x;

 }

 template <class _Tp>

 inline bool  _STLP_CALL

 operator>=(const _Deque_iterator<_Tp, _Nonconst_traits<_Tp> >& __x,

            const _Deque_iterator<_Tp, _Const_traits<_Tp> >& __y) { 

     return !(__x < __y);

 }

 template <class _Tp>

 inline bool _STLP_CALL

 operator<=(const _Deque_iterator<_Tp, _Nonconst_traits<_Tp> >& __x,

            const _Deque_iterator<_Tp, _Const_traits<_Tp> >& __y) { 

     return !(__y < __x);

 }

 # endif

 # ifdef _STLP_USE_OLD_HP_ITERATOR_QUERIES

 template <class _Tp, class _Traits> inline _Tp*  _STLP_CALL value_type(const _Deque_iterator<_Tp, _Traits  >&) { return (_Tp*)0; }

 template <class _Tp, class _Traits> inline random_access_iterator_tag _STLP_CALL 

 iterator_category(const _Deque_iterator<_Tp, _Traits  >&) { return random_access_iterator_tag(); }

 template <class _Tp, class _Traits> inline ptrdiff_t* _STLP_CALL 

 distance_type(const _Deque_iterator<_Tp, _Traits  >&) { return 0; }

 #endif

 // Deque base class.  It has two purposes.  First, its constructor

 //  and destructor allocate (but don't initialize) storage.  This makes

 //  exception safety easier.  Second, the base class encapsulates all of

 //  the differences between SGI-style allocators and standard-conforming

 //  allocators.

 template <class _Tp, class _Alloc>

 class _Deque_base 

 {

 public:

   typedef _Tp value_type;

   _STLP_FORCE_ALLOCATORS(_Tp, _Alloc)

   typedef typename _Alloc_traits<_Tp,_Alloc>::allocator_type  allocator_type;

   typedef typename _Alloc_traits<_Tp*, _Alloc>::allocator_type _Map_alloc_type;

   typedef _Deque_iterator<_Tp, _Nonconst_traits<_Tp> > iterator;

   typedef _Deque_iterator<_Tp, _Const_traits<_Tp> >   const_iterator;

   typedef _Deque_base<_Tp, _Alloc> _Base;

   static size_t  _STLP_CALL buffer_size() { return (size_t)_Deque_iterator_base<_Tp>::__buffer_size; } 

   _Deque_base(const allocator_type& __a, size_t __num_elements)

     : _M_start(), _M_finish(), _M_map(_STLP_CONVERT_ALLOCATOR(__a, _Tp*), 0),

       _M_map_size(__a, (size_t)0) {

     _STLP_PUSH_CLEANUP_ITEM(_Base, this) 

     _M_initialize_map(__num_elements);

   }

   _Deque_base(const allocator_type& __a)

     : _M_start(), _M_finish(), _M_map(_STLP_CONVERT_ALLOCATOR(__a, _Tp*), 0), 

       _M_map_size(__a, (size_t)0) {

      _STLP_PUSH_CLEANUP_ITEM(_Base, this)

   }

   ~_Deque_base();

 protected:

   void _M_initialize_map(size_t);

   void _M_create_nodes(_Tp** __nstart, _Tp** __nfinish);

   void _M_destroy_nodes(_Tp** __nstart, _Tp** __nfinish);

   enum { _S_initial_map_size = 8 };

 protected:

   iterator _M_start;

   iterator _M_finish;

   _STLP_alloc_proxy<value_type**, value_type*, _Map_alloc_type>  _M_map;

   _STLP_alloc_proxy<size_t, value_type,  allocator_type>   _M_map_size;  

 };

 template <class _Tp, _STLP_DEFAULT_ALLOCATOR_SELECT(_Tp) >

 class deque : public _Deque_base<_Tp, _Alloc> {

   typedef _Deque_base<_Tp, _Alloc> _Base;

   typedef deque<_Tp, _Alloc> _Self;

 public:                         // Basic types

   typedef _Tp value_type;

   typedef value_type* pointer;

   typedef const value_type* const_pointer;

   typedef value_type& reference;

   typedef const value_type& const_reference;

   typedef size_t size_type;

   typedef ptrdiff_t difference_type;

   typedef random_access_iterator_tag _Iterator_category;

   _STLP_FORCE_ALLOCATORS(_Tp, _Alloc)

   typedef typename _Base::allocator_type allocator_type;

 public:                         // Iterators

   typedef typename _Base::iterator       iterator;

   typedef typename _Base::const_iterator const_iterator;

   _STLP_DECLARE_RANDOM_ACCESS_REVERSE_ITERATORS;

 protected:                      // Internal typedefs

   typedef pointer* _Map_pointer;

   typedef typename  __type_traits<_Tp>::has_trivial_assignment_operator _TrivialAss;

   typedef typename  __type_traits<_Tp>::has_trivial_assignment_operator _IsPODType;

 public:                         // Basic accessors

   iterator begin() { return this->_M_start; }

   iterator end() { return this->_M_finish; }

   const_iterator begin() const { return const_iterator(this->_M_start); }

   const_iterator end() const { return const_iterator(this->_M_finish); }

   reverse_iterator rbegin() { return reverse_iterator(this->_M_finish); }

   reverse_iterator rend() { return reverse_iterator(this->_M_start); }

   const_reverse_iterator rbegin() const 

     { return const_reverse_iterator(this->_M_finish); }

   const_reverse_iterator rend() const 

     { return const_reverse_iterator(this->_M_start); }

   reference operator[](size_type __n)

     { return this->_M_start[difference_type(__n)]; }

   const_reference operator[](size_type __n) const 

     { return this->_M_start[difference_type(__n)]; }

   void _M_range_check(size_type __n) const {

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

       __stl_throw_out_of_range("deque");

   }

   reference at(size_type __n)

     { _M_range_check(__n); return (*this)[__n]; }

   const_reference at(size_type __n) const

     { _M_range_check(__n); return (*this)[__n]; }

   reference front() { return *this->_M_start; }

   reference back() {

     iterator __tmp = this->_M_finish;

     --__tmp;

     return *__tmp;

   }

   const_reference front() const { return *this->_M_start; }

   const_reference back() const {

     const_iterator __tmp = this->_M_finish;

     --__tmp;

     return *__tmp;

   }

   size_type size() const { return this->_M_finish - this->_M_start; }

   size_type max_size() const { return size_type(-1); }

   bool empty() const { return this->_M_finish == this->_M_start; }

   allocator_type get_allocator() const { return this->_M_map_size; }

 public:                         // Constructor, destructor.

   explicit deque(const allocator_type& __a = allocator_type()) 

     : _Deque_base<_Tp, _Alloc>(__a, 0) {

     _STLP_POP_CLEANUP_ITEM

   }

   deque(const _Self& __x) : 

     _Deque_base<_Tp, _Alloc>(__x.get_allocator(), __x.size()) {  

     uninitialized_copy(__x.begin(), __x.end(), this->_M_start); 

     _STLP_POP_CLEANUP_ITEM

   }

   deque(size_type __n, const value_type& __val,

         const allocator_type& __a = allocator_type()) : 

     _Deque_base<_Tp, _Alloc>(__a, __n)

     {

       _M_fill_initialize(__val); 

       _STLP_POP_CLEANUP_ITEM

     }

   // int,long variants may be needed 

   explicit deque(size_type __n) : _Deque_base<_Tp, _Alloc>(allocator_type(), __n)

   { 

 #ifdef __SYMBIAN32__

 // Though the below code is for Symbian

 // we are not using cleanup stack with this version.

     _M_fill_initialize(value_type()); 

 #else    

     value_type __p;

     _STLP_PUSH_CLEANUP_ITEM(_Tp, &__p) 	    

     _M_fill_initialize(__p); 

     // unconditional for __p

 //    CleanupStack::Pop();

     _STLP_POP_CLEANUP_ITEM

 #endif // __SYMBIAN32__    

   }

 #ifdef _STLP_MEMBER_TEMPLATES

   template <class _Integer>

   void _M_initialize_dispatch(_Integer __n, _Integer __x, const __true_type&) {

     this->_M_initialize_map(__n);

     _M_fill_initialize(__x);

   }

   template <class _InputIter>

   void _M_initialize_dispatch(_InputIter __first, _InputIter __last,

                               const __false_type&) {

     _M_range_initialize(__first, __last, _STLP_ITERATOR_CATEGORY(__first, _InputIter));

   }

 # ifdef _STLP_NEEDS_EXTRA_TEMPLATE_CONSTRUCTORS

   // VC++ needs this

   template <class _InputIterator>

   deque(_InputIterator __first, _InputIterator __last) : 

     _Deque_base<_Tp, _Alloc>(allocator_type()) {

     typedef typename _Is_integer<_InputIterator>::_Integral _Integral;

     _M_initialize_dispatch(__first, __last, _Integral());

     _STLP_POP_CLEANUP_ITEM

   }

 # endif

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

   template <class _InputIterator>

   deque(_InputIterator __first, _InputIterator __last,

         const allocator_type& __a _STLP_ALLOCATOR_TYPE_DFL) : 

     _Deque_base<_Tp, _Alloc>(__a) {

     typedef typename _Is_integer<_InputIterator>::_Integral _Integral;

     _M_initialize_dispatch(__first, __last, _Integral());

     _STLP_POP_CLEANUP_ITEM

   }

 # else

   deque(const value_type* __first, const value_type* __last,

         const allocator_type& __a = allocator_type() ) 

     : _Deque_base<_Tp, _Alloc>(__a, __last - __first) {  

     __uninitialized_copy(__first, __last, this->_M_start, _IsPODType()); 

     _STLP_POP_CLEANUP_ITEM

   }

   deque(const_iterator __first, const_iterator __last,

         const allocator_type& __a = allocator_type() ) 

     : _Deque_base<_Tp, _Alloc>(__a, __last - __first) { 

     __uninitialized_copy(__first, __last, this->_M_start, _IsPODType()); 

     _STLP_POP_CLEANUP_ITEM

   }

 #endif /* _STLP_MEMBER_TEMPLATES */

   ~deque() { 

     _STLP_STD::_Destroy(this->_M_start, this->_M_finish); 

   }

   _Self& operator= (const _Self& __x);

   void swap(_Self& __x) {

     _STLP_STD::swap(this->_M_start, __x._M_start);

     _STLP_STD::swap(this->_M_finish, __x._M_finish);

     _STLP_STD::swap(this->_M_map, __x._M_map);

     _STLP_STD::swap(this->_M_map_size, __x._M_map_size);

   }

 #ifdef _STLP_USE_TRAP_LEAVE

 public:

   static void* operator new (size_t __n, TLeave) { return _STLP_StackHelper<bool>::_NewLC(__n); }

   static void* operator new (size_t __n) { return _STLP_StackHelper<bool>::_NewLC(__n); }

 #endif

 public: 

   // assign(), a generalized assignment member function.  Two

   // versions: one that takes a count, and one that takes a range.

   // The range version is a member template, so we dispatch on whether

   // or not the type is an integer.

   void _M_fill_assign(size_type __n, const _Tp& __val) {

     if (__n > size()) {

       _STLP_STD::fill(begin(), end(), __val);

       insert(end(), __n - size(), __val);

     }

     else {

       erase(begin() + __n, end());

       _STLP_STD::fill(begin(), end(), __val);

     }

   }

   void assign(size_type __n, const _Tp& __val) {

     _M_fill_assign(__n, __val);

   }

 #ifdef _STLP_MEMBER_TEMPLATES

   template <class _InputIterator>

   void assign(_InputIterator __first, _InputIterator __last) {

     typedef typename _Is_integer<_InputIterator>::_Integral _Integral;

     _M_assign_dispatch(__first, __last, _Integral());

   }

 private:                        // helper functions for assign() 

   template <class _Integer>

   void _M_assign_dispatch(_Integer __n, _Integer __val, const __true_type&)

     { _M_fill_assign((size_type) __n, (_Tp) __val); }

   template <class _InputIterator>

   void _M_assign_dispatch(_InputIterator __first, _InputIterator __last,

                           const __false_type&) {

     _M_assign_aux(__first, __last, _STLP_ITERATOR_CATEGORY(__first, _InputIterator));

   }

   template <class _InputIter>

   void _M_assign_aux(_InputIter __first, _InputIter __last, const input_iterator_tag &) {

     iterator __cur = begin();

     for ( ; __first != __last && __cur != end(); ++__cur, ++__first)

       *__cur = *__first;

     if (__first == __last)

       erase(__cur, end());

     else

       insert(end(), __first, __last);

   }

   template <class _ForwardIterator>

   void _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last,

                      const forward_iterator_tag &) {

     size_type __len = distance(__first, __last);

     if (__len > size()) {

       _ForwardIterator __mid = __first;

       advance(__mid, size());

       copy(__first, __mid, begin());

       insert(end(), __mid, __last);

     }

     else

       erase(copy(__first, __last, begin()), end());

   }

 #endif /* _STLP_MEMBER_TEMPLATES */

 public:                         // push_* and pop_*

   void push_back(const value_type& __t) {

     if (this->_M_finish._M_cur != this->_M_finish._M_last - 1) {

       _Construct(this->_M_finish._M_cur, __t);

       ++this->_M_finish._M_cur;

     }

     else

       _M_push_back_aux_v(__t);

   }

   void push_front(const value_type& __t) {

     if (this->_M_start._M_cur != this->_M_start._M_first) {

       _Construct(this->_M_start._M_cur - 1, __t);

       --this->_M_start._M_cur;

     }

     else

       _M_push_front_aux_v(__t);

   }

 # ifndef _STLP_NO_ANACHRONISMS

   void push_back() {

     if (this->_M_finish._M_cur != this->_M_finish._M_last - 1) {

       _Construct(this->_M_finish._M_cur);

       ++this->_M_finish._M_cur;

     }

     else

       _M_push_back_aux();

   }

   void push_front() {

     if (this->_M_start._M_cur != this->_M_start._M_first) {

       _Construct(this->_M_start._M_cur - 1);

       --this->_M_start._M_cur;

     }

     else

       _M_push_front_aux();

   }

 # endif

   void pop_back() {

     if (this->_M_finish._M_cur != this->_M_finish._M_first) {

       --this->_M_finish._M_cur;

       _STLP_STD::_Destroy(this->_M_finish._M_cur);

     }

     else

       _M_pop_back_aux();

   }

   void pop_front() {

     if (this->_M_start._M_cur != this->_M_start._M_last - 1) {

       _STLP_STD::_Destroy(this->_M_start._M_cur);

       ++this->_M_start._M_cur;

     }

     else 

       _M_pop_front_aux();

   }

 public:                         // Insert

   iterator insert(iterator __position, const value_type& __x) {

     if (__position._M_cur == this->_M_start._M_cur) {

       push_front(__x);

       return this->_M_start;

     }

     else if (__position._M_cur == this->_M_finish._M_cur) {

       push_back(__x);

       iterator __tmp = this->_M_finish;

       --__tmp;

       return __tmp;

     }

     else {

       return _M_insert_aux(__position, __x);

     }

   }

   iterator insert(iterator __position)

     { return insert(__position, value_type()); }

   void insert(iterator __pos, size_type __n, const value_type& __x) {

     _M_fill_insert(__pos, __n, __x);

   }

   void _M_fill_insert(iterator __pos, size_type __n, const value_type& __x);

 #ifdef _STLP_MEMBER_TEMPLATES  

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

   template <class _InputIterator>

   void insert(iterator __pos, _InputIterator __first, _InputIterator __last) {

     typedef typename _Is_integer<_InputIterator>::_Integral _Integral;

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

   }

   template <class _Integer>

   void _M_insert_dispatch(iterator __pos, _Integer __n, _Integer __x,

                           const __true_type&) {

     _M_fill_insert(__pos, (size_type) __n, (value_type) __x);

   }

   template <class _InputIterator>

   void _M_insert_dispatch(iterator __pos,

                           _InputIterator __first, _InputIterator __last,

                           const __false_type&) {

     insert(__pos, __first, __last, _STLP_ITERATOR_CATEGORY(__first, _InputIterator));

   }

 #else /* _STLP_MEMBER_TEMPLATES */

   void insert(iterator __pos,

               const value_type* __first, const value_type* __last);

   void insert(iterator __pos,

               const_iterator __first, const_iterator __last);

 #endif /* _STLP_MEMBER_TEMPLATES */

   void resize(size_type __new_size, value_type __x) {

     const size_type __len = size();

     if (__new_size < __len) 

       erase(this->_M_start + __new_size, this->_M_finish);

     else

       insert(this->_M_finish, __new_size - __len, __x);

   }

   void resize(size_type new_size) { resize(new_size, value_type()); }

 public:                         // Erase

   iterator erase(iterator __pos) {

     iterator __next = __pos;

     ++__next;

     difference_type __index = __pos - this->_M_start;

     if (size_type(__index) < this->size() >> 1) {

       copy_backward(this->_M_start, __pos, __next);

       pop_front();

     }

     else {

       copy(__next, this->_M_finish, __pos);

       pop_back();

     }

     return this->_M_start + __index;

   }

   iterator erase(iterator __first, iterator __last);

   void clear(); 

 protected:                        // Internal construction/destruction

   void _M_fill_initialize(const value_type& __val);

 #ifdef _STLP_MEMBER_TEMPLATES 

   template <class _InputIterator>

   void _M_range_initialize(_InputIterator __first,

 			   _InputIterator __last,

 			   const input_iterator_tag &) {

     this->_M_initialize_map(0);

     _STLP_TRY {

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

         push_back(*__first);

     }

     _STLP_UNWIND(clear());

   }

  template <class _ForwardIterator>

  void  _M_range_initialize(_ForwardIterator __first,

                            _ForwardIterator __last,

                            const forward_iterator_tag &)  {

    size_type __n = distance(__first, __last);

    this->_M_initialize_map(__n);

    _STLP_LEAVE_VOLATILE _Map_pointer __cur_node = 0 ;

    _STLP_TRY {

     for (__cur_node = this->_M_start._M_node; 

          __cur_node < this->_M_finish._M_node; 

 	 ++__cur_node) {

       _ForwardIterator __mid = __first;

       advance(__mid, this->buffer_size());

       uninitialized_copy(__first, __mid, *__cur_node);

       __first = __mid;

     }

     uninitialized_copy(__first, __last, this->_M_finish._M_first);

    }

   _STLP_UNWIND(_STLP_STD::_Destroy(this->_M_start, iterator(*__cur_node, __cur_node)));

  }

 #endif /* _STLP_MEMBER_TEMPLATES */

 protected:                        // Internal push_* and pop_*

   void _M_push_back_aux_v(const value_type&);

   void _M_push_front_aux_v(const value_type&);

 # ifndef _STLP_NO_ANACHRONISMS

   void _M_push_back_aux();

   void _M_push_front_aux();

 # endif

   void _M_pop_back_aux();

   void _M_pop_front_aux();

 protected:                        // Internal insert functions

 #ifdef _STLP_MEMBER_TEMPLATES

 template <class _InputIterator>

 void 

 insert(iterator __pos,

        _InputIterator __first,

        _InputIterator __last,

        const input_iterator_tag &)

 {

   copy(__first, __last, inserter(*this, __pos));

 }

 template <class _ForwardIterator>

 void  insert(iterator __pos,

 	     _ForwardIterator __first,

 	     _ForwardIterator __last,

 	     const forward_iterator_tag &)

  {

   size_type __n = distance(__first, __last);

   if (__pos._M_cur == this->_M_start._M_cur) {

     iterator __new_start = _M_reserve_elements_at_front(__n);

     _STLP_TRY {

       uninitialized_copy(__first, __last, __new_start);

       this->_M_start = __new_start;

     }

     _STLP_UNWIND(this->_M_destroy_nodes(__new_start._M_node, this->_M_start._M_node));

   }

   else if (__pos._M_cur == this->_M_finish._M_cur) {

     iterator __new_finish = _M_reserve_elements_at_back(__n);

     _STLP_TRY {

       uninitialized_copy(__first, __last, this->_M_finish);

       this->_M_finish = __new_finish;

     }

     _STLP_UNWIND(this->_M_destroy_nodes(this->_M_finish._M_node + 1, __new_finish._M_node + 1));

   }

   else

     _M_insert_aux(__pos, __first, __last, __n);

 }

 #endif /* _STLP_MEMBER_TEMPLATES */

   iterator _M_insert_aux(iterator __pos, const value_type& __x);

   iterator _M_insert_aux(iterator __pos);

   iterator _M_insert_aux_prepare(iterator __pos);

   void _M_insert_aux(iterator __pos, size_type __n, const value_type& __x);

 #ifdef _STLP_MEMBER_TEMPLATES  

   template <class _ForwardIterator>

   void _M_insert_aux(iterator __pos,

                      _ForwardIterator __first,

                      _ForwardIterator __last,

                      size_type __n) {

     const difference_type __elemsbefore = __pos - this->_M_start;

     size_type __length = size();

     if (__elemsbefore < difference_type(__length / 2)) {

       iterator __new_start = _M_reserve_elements_at_front(__n);

       iterator __old_start = this->_M_start;

       __pos = this->_M_start + __elemsbefore;

       _STLP_TRY {

 	if (__elemsbefore >= difference_type(__n)) {

 	  iterator __start_n = this->_M_start + difference_type(__n); 

 	  uninitialized_copy(this->_M_start, __start_n, __new_start);

 	  this->_M_start = __new_start;

 	  copy(__start_n, __pos, __old_start);

 	  copy(__first, __last, __pos - difference_type(__n));

 	}

 	else {

 	  _ForwardIterator __mid = __first;

 	  advance(__mid, difference_type(__n) - __elemsbefore);

 	  __uninitialized_copy_copy(this->_M_start, __pos, __first, __mid,

 				    __new_start, _IsPODType());

 	  this->_M_start = __new_start;

 	  copy(__mid, __last, __old_start);

 	}

       }

       _STLP_UNWIND(this->_M_destroy_nodes(__new_start._M_node, this->_M_start._M_node));

     }

     else {

       iterator __new_finish = _M_reserve_elements_at_back(__n);

       iterator __old_finish = this->_M_finish;

       const difference_type __elemsafter = 

 	difference_type(__length) - __elemsbefore;

       __pos = this->_M_finish - __elemsafter;

       _STLP_TRY {

       if (__elemsafter > difference_type(__n)) {

         iterator __finish_n = this->_M_finish - difference_type(__n);

         uninitialized_copy(__finish_n, this->_M_finish, this->_M_finish);

         this->_M_finish = __new_finish;

         copy_backward(__pos, __finish_n, __old_finish);

         copy(__first, __last, __pos);

       }

       else {

         _ForwardIterator __mid = __first;

         advance(__mid, __elemsafter);

         __uninitialized_copy_copy(__mid, __last, __pos, this->_M_finish, this->_M_finish, _IsPODType());

         this->_M_finish = __new_finish;

         copy(__first, __mid, __pos);

       }

       }

       _STLP_UNWIND(this->_M_destroy_nodes(this->_M_finish._M_node + 1, __new_finish._M_node + 1));

     }

   }

 #else /* _STLP_MEMBER_TEMPLATES */

   void _M_insert_aux(iterator __pos,

                      const value_type* __first, const value_type* __last,

                      size_type __n);

   void _M_insert_aux(iterator __pos, 

                      const_iterator __first, const_iterator __last,

                      size_type __n);

 #endif /* _STLP_MEMBER_TEMPLATES */

   iterator _M_reserve_elements_at_front(size_type __n) {

     size_type __vacancies = this->_M_start._M_cur - this->_M_start._M_first;

     if (__n > __vacancies) 

       _M_new_elements_at_front(__n - __vacancies);

     return this->_M_start - difference_type(__n);

   }

   iterator _M_reserve_elements_at_back(size_type __n) {

     size_type __vacancies = (this->_M_finish._M_last - this->_M_finish._M_cur) - 1;

     if (__n > __vacancies)

       _M_new_elements_at_back(__n - __vacancies);

     return this->_M_finish + difference_type(__n);

   }

   void _M_new_elements_at_front(size_type __new_elements);

   void _M_new_elements_at_back(size_type __new_elements);

 protected:                      // Allocation of _M_map and nodes

   // Makes sure the _M_map has space for new nodes.  Does not actually

   //  add the nodes.  Can invalidate _M_map pointers.  (And consequently, 

   //  deque iterators.)

   void _M_reserve_map_at_back (size_type __nodes_to_add = 1) {

     if (__nodes_to_add + 1 > this->_M_map_size._M_data - (this->_M_finish._M_node - this->_M_map._M_data))

       _M_reallocate_map(__nodes_to_add, false);

   }

   void _M_reserve_map_at_front (size_type __nodes_to_add = 1) {

     if (__nodes_to_add > size_type(this->_M_start._M_node - this->_M_map._M_data))

       _M_reallocate_map(__nodes_to_add, true);

   }

   void _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front);

 };

 # define _STLP_TEMPLATE_CONTAINER deque<_Tp, _Alloc>

 # define _STLP_TEMPLATE_HEADER    template <class _Tp, class _Alloc>

 # include <stl/_relops_cont.h>

 # undef _STLP_TEMPLATE_CONTAINER

 # undef _STLP_TEMPLATE_HEADER

 _STLP_END_NAMESPACE 

 // do a cleanup

 # undef deque

 # undef __deque__

 # define __deque__ __WORKAROUND_DBG_RENAME(deque)

 # if !defined (_STLP_LINK_TIME_INSTANTIATION)

 #  include <stl/_deque.c>

 # endif

 #if defined (_STLP_DEBUG)

 # include <stl/debug/_deque.h>

 #endif

 # if defined (_STLP_USE_WRAPPER_FOR_ALLOC_PARAM)

 #  include <stl/wrappers/_deque.h>

 # endif

 #endif /* _STLP_INTERNAL_DEQUE_H */

 // Local Variables:

 // mode:C++

 // End: