// deque standard header
#ifndef _DEQUE_
#define _DEQUE_
#include <iterator>
#include <memory>
#include <stdexcept>
#include <xutility>

#ifdef  _MSC_VER
#pragma pack(push,8)
#endif  /* _MSC_VER */
_STD_BEGIN
#define _DEQUEMAPSIZ	2
#define _DEQUESIZ (4096 < sizeof (_Ty) ? 1 : 4096 / sizeof (_Ty))
		// TEMPLATE CLASS deque
template<class _Ty, class _A = allocator<_Ty> >
	class deque {
public:
	typedef deque<_Ty, _A> _Myt;
	typedef _A allocator_type;
	typedef typename _A::size_type size_type;
	typedef typename _A::difference_type difference_type;
	typedef typename _A::pointer _Tptr;
	typedef typename _A::const_pointer _Ctptr;
	typedef _POINTER_X(_Tptr, _A) _Mapptr;
	typedef typename _A::reference reference;
	typedef typename _A::const_reference const_reference;
	typedef typename _A::value_type value_type;
		// CLASS iterator
	class iterator : public _Ranit<_Ty, difference_type> {
	public:
		friend class deque<_Ty, _A>;
		iterator()
			: _First(0), _Last(0), _Next(0), _Map(0) {}
		iterator(_Tptr _P, _Mapptr _M)
			: _First(*_M), _Last(*_M + _DEQUESIZ),
				_Next(_P), _Map(_M) {}
		reference operator*() const
			{return (*_Next); }
		_Tptr operator->() const
			{return (&**this); }
		iterator& operator++()
			{if (++_Next == _Last)
				{_First = *++_Map;
				_Last = _First + _DEQUESIZ;
				_Next = _First; }
			return (*this); }
		iterator operator++(int)
			{iterator _Tmp = *this;
			++*this;
			return (_Tmp); }
		iterator& operator--()
			{if (_Next == _First)
				{_First = *--_Map;
				_Last = _First + _DEQUESIZ;
				_Next = _Last; }
			--_Next;
			return (*this); }
		iterator operator--(int)
			{iterator _Tmp = *this;
			--*this;
			return (_Tmp); }
		iterator& operator+=(difference_type _N)
			{_Add(_N);
			return (*this); }
		iterator& operator-=(difference_type _N)
			{return (*this += -_N); }
		iterator operator+(difference_type _N) const
			{iterator _Tmp = *this;
			return (_Tmp += _N); }
		iterator operator-(difference_type _N) const
			{iterator _Tmp = *this;
			return (_Tmp -= _N); }
		difference_type operator-(const iterator& _X) const
			{return (_Map == _X._Map ? _Next - _X._Next
				: _DEQUESIZ * (_Map - _X._Map - 1)
				+ (_Next - _First) + (_X._Last - _X._Next)); }
		reference operator[](difference_type _N) const
			{return (*(*this + _N)); }
		bool operator==(const iterator& _X) const
			{return (_Next == _X._Next); }
		bool operator!=(const iterator& _X) const
			{return (!(*this == _X)); }
		bool operator<(const iterator& _X) const
			{return (_Map < _X._Map
				|| _Map == _X._Map && _Next < _X._Next); }
		bool operator<=(const iterator& _X) const
			{return (!(_X < *this)); }
		bool operator>(const iterator& _X) const
			{return (_X < *this); }
		bool operator>=(const iterator& _X) const
			{return (!(*this < _X)); }
	protected:
		void _Add(difference_type _N)
			{difference_type _Off = _N + _Next - _First;
			difference_type _Moff = (0 <= _Off)
				? _Off / (difference_type)_DEQUESIZ
				: -((((difference_type)_DEQUESIZ) - 1 - _Off) / ((difference_type)_DEQUESIZ));
			if (_Moff == 0)
				_Next += _N;
			else
				{_Map += _Moff;
				_First = *_Map;
				_Last = _First + _DEQUESIZ;
				_Next = _First + (_Off - _Moff * _DEQUESIZ); }}
	_PROTECTED:
		_Tptr _First, _Last, _Next;
		_Mapptr _Map;
		};
		// CLASS const_iterator
	class const_iterator : public iterator {
	public:
		const_iterator()
			{}
		const_iterator(_Tptr _P, _Mapptr _M)
			: iterator(_P, _M) {}
		const_iterator(const iterator& _X)
			: iterator(_X) {}
		const_reference operator*() const
			{return (*_Next); }
		_Ctptr operator->() const
			{return (&**this); }
		const_iterator& operator++()
			{if (++_Next == _Last)
				{_First = *++_Map;
				_Last = _First + _DEQUESIZ;
				_Next = _First; }
			return (*this); }
		const_iterator operator++(int)
			{const_iterator _Tmp = *this;
			++*this;
			return (_Tmp); }
		const_iterator& operator--()
			{if (_Next == _First)
				{_First = *--_Map;
				_Last = _First + _DEQUESIZ;
				_Next = _Last; }
			--_Next;
			return (*this); }
		const_iterator operator--(int)
			{const_iterator _Tmp = *this;
			--*this;
			return (_Tmp); }
		const_iterator& operator+=(difference_type _N)
			{_Add(_N);
			return (*this); }
		const_iterator& operator-=(difference_type _N)
			{return (*this += -_N); }
		const_iterator operator+(difference_type _N) const
			{iterator _Tmp = *this;
			return (_Tmp += _N); }
		const_iterator operator-(difference_type _N) const
			{iterator _Tmp = *this;
			return (_Tmp -= _N); }
		difference_type operator-(const const_iterator& _X) const
			{return (_Map == _X._Map ? _Next - _X._Next
				: _DEQUESIZ * (_Map - _X._Map - 1)
				+ (_Next - _First) + (_X._Last - _X._Next)); }
		const_reference operator[](difference_type _N) const
			{return (*(*this + _N)); }
		bool operator==(const const_iterator& _X) const
			{return (_Next == _X._Next); }
		bool operator!=(const const_iterator& _X) const
			{return (!(*this == _X)); }
		bool operator<(const const_iterator& _X) const
			{return (_Map < _X._Map
				|| _Map == _X._Map && _Next < _X._Next); }
		bool operator<=(const const_iterator& _X) const
			{return (!(_X < *this)); }
		bool operator>(const const_iterator& _X) const
			{return (_X < *this); }
		bool operator>=(const const_iterator& _X) const
			{return (!(*this < _X)); }
		};
	typedef reverse_iterator<const_iterator, value_type,
		const_reference, _Ctptr, difference_type>
			const_reverse_iterator;
	typedef reverse_iterator<iterator, value_type,
		reference, _Tptr, difference_type>
			reverse_iterator;
	explicit deque(const _A& _Al = _A())
		: allocator(_Al),
			_First(), _Last(), _Map(0), _Mapsize(0), _Size(0)
		{}
	explicit deque(size_type _N, const _Ty& _V = _Ty(),
		const _A& _Al = _A())
		: allocator(_Al),
			_First(), _Last(), _Map(0), _Mapsize(0), _Size(0)
		{insert(begin(), _N, _V); }
	deque(const _Myt& _X)
		: allocator(_X.allocator),
			_First(), _Last(), _Map(0), _Mapsize(0), _Size(0)
		{copy(_X.begin(), _X.end(), back_inserter(*this)); }
	typedef const_iterator _It;
		deque(_It _F, _It _L, const _A& _Al = _A())
		: allocator(_Al),
			_First(), _Last(), _Map(0), _Mapsize(0), _Size(0)
		{copy(_F, _L, back_inserter(*this)); }
	~deque()
		{while (!empty())
			pop_front(); }
	_Myt& operator=(const _Myt& _X)
		{if (this != &_X)
			{iterator _S;
			if (_X.size() <= size())
				{_S = copy(_X.begin(), _X.end(), begin());
				erase(_S, end()); }
			else
				{const_iterator _Sx = _X.begin() + size();
				_S = copy(_X.begin(), _Sx, begin());
				copy(_Sx, _X.end(), inserter(*this, _S)); }}
		return (*this); }
	iterator begin()
		{return (_First); }
	const_iterator begin() const
		{return ((const_iterator)_First); }
	iterator end()
		{return (_Last); }
	const_iterator end() const
		{return ((const_iterator)_Last); }
	reverse_iterator rbegin()
		{return (reverse_iterator(end())); }
	const_reverse_iterator rbegin() const
		{return (const_reverse_iterator(end())); }
	reverse_iterator rend()
		{return (reverse_iterator(begin())); }
	const_reverse_iterator rend() const
		{return (const_reverse_iterator(begin())); }
	void resize(size_type _N, _Ty _X = _Ty())
		{if (size() < _N)
			insert(end(), _N - size(), _X);
		else if (_N < size())
			erase(begin() + _N, end()); }
	size_type size() const
		{return (_Size); }
	size_type max_size() const
		{return (allocator.max_size()); }
	bool empty() const
		{return (size() == 0); }
	_A get_allocator() const
		{return (allocator); }
	const_reference at(size_type _P) const
		{if (size() <= _P)
			_Xran();
		return (*(begin() + _P)); }
	reference at(size_type _P)
		{if (size() <= _P)
			_Xran();
		return (*(begin() + _P)); }
	const_reference operator[](size_type _P) const
		{return (*(begin() + _P)); }
	reference operator[](size_type _P)
		{return (*(begin() + _P)); }
	reference front()
		{return (*begin()); }
	const_reference front() const
		{return (*begin()); }
	reference back()
		{return (*(end() - 1)); }
	const_reference back() const
		{return (*(end() - 1)); }
	void push_front(const _Ty& _X)
		{if (empty() || _First._Next == _First._First)
			_Buyfront();
		allocator.construct(--_First._Next, _X);
		++_Size; }
	void pop_front()
		{allocator.destroy(_First._Next++);
		--_Size;
		if (empty() || _First._Next == _First._Last)
			_Freefront(); }
	void push_back(const _Ty& _X)
		{if (empty() || _Last._Next == _Last._Last)
			{_Buyback();
			allocator.construct(_Last._Next++, _X); }
		else if (_Last._Next + 1 == _Last._Last)
			{allocator.construct(_Last._Next++, _X);
			_Buyback(); }
		else
			allocator.construct(_Last._Next++, _X);
		++_Size; }
	void pop_back()
		{
		if (_Last._Next == _Last._First)
			_Freeback();
		if (!empty())
			allocator.destroy(--_Last._Next);
        --_Size;
        if ( empty())
            _Freeback(); }
	void assign(_It _F, _It _L)
		{erase(begin(), end());
		insert(begin(), _F, _L); }
	void assign(size_type _N, const _Ty& _X = _Ty())
		{erase(begin(), end());
		insert(begin(), _N, _X); }
	iterator insert(iterator _P, const _Ty& _X = _Ty())
		{if (_P == begin())
			{push_front(_X);
			return (begin()); }
		else if (_P == end())
			{push_back(_X);
			return (end() - 1); }
		else
			{iterator _S;
			size_type _Off = _P - begin();
			if (_Off < size() / 2)
				{push_front(front());
				_S = begin() + _Off;
				copy(begin() + 2, _S + 1, begin() + 1); }
			else
				{push_back(back());
				_S = begin() + _Off;
				copy_backward(_S, end() - 2, end() - 1); }
			*_S = _X;
			return (_S); }}
	void insert(iterator _P, size_type _M, const _Ty& _X)
		{iterator _S;
		size_type _I;
		size_type _Off = _P - begin();
		size_type _Rem = _Size - _Off;
		if (_Off < _Rem)
			if (_Off < _M)
				{for (_I = _M - _Off; 0 < _I; --_I)
					push_front(_X);
				for (_I = _Off; 0 < _I; --_I)
					push_front(begin()[_M - 1]);
				_S = begin() + _M;
				fill(_S, _S + _Off, _X); }
			else
				{for (_I = _M; 0 < _I; --_I)
					push_front(begin()[_M - 1]);
				_S = begin() + _M;
				copy(_S + _M, _S + _Off, _S);
				fill(begin() + _Off, _S + _Off, _X); }
		else
			if (_Rem < _M)
				{for (_I = _M - _Rem; 0 < _I; --_I)
					push_back(_X);
				for (_I = 0; _I < _Rem; ++_I)
					push_back(begin()[_Off + _I]);
				_S = begin() + _Off;
				fill(_S, _S + _Rem, _X); }
			else
				{for (_I = 0; _I < _M; ++_I)
					push_back(begin()[_Off + _Rem - _M + _I]);
				_S = begin() + _Off;
				copy_backward(_S, _S + _Rem - _M, _S + _Rem);
				fill(_S, _S + _M, _X); }}
	void insert(iterator _P, _It _F, _It _L)
		{size_type _M = 0;
		_Distance(_F, _L, _M);
		size_type _I;
		size_type _Off = _P - begin();
		size_type _Rem = _Size - _Off;
		if (_Off < _Rem)
			if (_Off < _M)
				{_It _Qx = _F;
				advance(_Qx, _M - _Off);
				for (_It _Q = _Qx; _F != _Q; )
					push_front(*--_Q);
				for (_I = _Off; 0 < _I; --_I)
					push_front(begin()[_M - 1]);
				copy(_Qx, _L, begin() + _M); }
			else
				{for (_I = _M; 0 < _I; --_I)
					push_front(begin()[_M - 1]);
				iterator _S = begin() + _M;
				copy(_S + _M, _S + _Off, _S);
				copy(_F, _L, begin() + _Off); }
		else
			if (_Rem < _M)
				{_It _Qx = _F;
				advance(_Qx, _Rem);
				for (_It _Q = _Qx; _Q != _L; ++_Q)
					push_back(*_Q);
				for (_I = 0; _I < _Rem; ++_I)
					push_back(begin()[_Off + _I]);
				copy(_F, _Qx, begin() + _Off); }
			else
				{for (_I = 0; _I < _M; ++_I)
					push_back(begin()[_Off + _Rem - _M + _I]);
				iterator _S = begin() + _Off;
				copy_backward(_S, _S + _Rem - _M, _S + _Rem);
				copy(_F, _L, _S); }}
	iterator erase(iterator _P)
		{return (erase(_P, _P + 1)); }
	iterator erase(iterator _F, iterator _L)
		{size_type _N = _L - _F;
		size_type _M = _F - begin();
		if (_M < (size_type)(end() - _L))
			{copy_backward(begin(), _F, _L);
			for (; 0 < _N; --_N)
				pop_front(); }
		else
			{copy(_L, end(), _F);
			for (; 0 < _N; --_N)
				pop_back(); }
		return (_M == 0 ? begin() : begin() + _M); }
	void clear()
		{erase(begin(), end()); }
	void swap(_Myt& _X)
		{if (allocator == _X.allocator)
			{std::swap(_First, _X._First);
			std::swap(_Last, _X._Last);
			std::swap(_Map, _X._Map);
			std::swap(_Mapsize, _X._Mapsize);
			std::swap(_Size, _X._Size); }
		else
			{_Myt _Ts = *this; *this = _X, _X = _Ts; }}
	friend void swap(_Myt& _X, _Myt& _Y)
		{_X.swap(_Y); }
protected:
	void _Buyback()
		{_Tptr _P = allocator.allocate(_DEQUESIZ, (void *)0);
		if (empty())
			{_Mapsize = _DEQUEMAPSIZ;
			size_type _N = _Mapsize / 2;
			_Getmap();
			_Setptr(_Map + _N, _P);
			_First = iterator(_P + _DEQUESIZ / 2, _Map + _N);
			_Last = _First; }
		else if (_Last._Map < _Map + (_Mapsize - 1))
			{_Setptr(++_Last._Map, _P);
			_Last = iterator(_P, _Last._Map); }
		else
			{difference_type _I = _Last._Map - _First._Map + 1;
			_Mapptr _M = _Growmap(2 * _I);
			_Setptr(_M + _I, _P);
			_First = iterator(_First._Next, _M);
			_Last = iterator(_P, _M + _I); }}
	void _Buyfront()
		{_Tptr _P = allocator.allocate(_DEQUESIZ, (void *)0);
		if (empty())
			{_Mapsize = _DEQUEMAPSIZ;
			size_type _N = _Mapsize / 2;
			_Getmap();
			_Setptr(_Map + _N, _P);
			_First = iterator(_P + (_DEQUESIZ / 2 + 1),
				_Map + _N);
			_Last = _First; }
		else if (_Map < _First._Map)
			{_Setptr(--_First._Map, _P);
			_First = iterator(_P + _DEQUESIZ, _First._Map); }
		else if (_Last._Map == _First._Map)
			{_Setptr(_Last._Map++, *_First._Map);
			_Setptr(_First._Map+1, *_First._Map);
			_Setptr(_First._Map, _P);
			_First = iterator(_P + _DEQUESIZ, _First._Map); }
		else
			{difference_type _I = _Last._Map - _First._Map + 1;
			_Mapptr _M = _Growmap(2 * _I);
			_Setptr(--_M, _P);
			_First = iterator(_P + _DEQUESIZ, _M);
			_Last = iterator(_Last._Next, _M + _I); }}
	void _Freeback()
		{_Freeptr(_Last._Map--);
		if (empty())
			{
            if(_First._Map == _Last._Map)
                _Freeptr(_First._Map);
            _First = iterator();
			_Last = _First;
			_Freemap(); }
		else
			_Last = iterator(*_Last._Map + _DEQUESIZ,
				_Last._Map); }
	void _Freefront()
		{_Freeptr(_First._Map++);
		if (empty())
			{_First = iterator();
			_Last = _First;
			_Freemap(); }
		else
			_First = iterator(*_First._Map, _First._Map); }
	void _Xran() const
		{_THROW(out_of_range, "invalid deque<T> subscript"); }
	void _Freemap()
		{allocator.deallocate(_Map, _Mapsize); }
	void _Freeptr(_Mapptr _M)
		{allocator.deallocate(*_M, _DEQUESIZ); }
	void _Getmap()
		{_Map = (_Mapptr)allocator._Charalloc(
			_Mapsize * sizeof (_Tptr)); }
	_Mapptr _Growmap(size_type _Newsize)
		{_Mapptr _M = (_Mapptr)allocator._Charalloc(
			_Newsize * sizeof (_Tptr));
		copy(_First._Map, _Last._Map + 1,
			_M + _Newsize / 4);
		allocator.deallocate(_Map, _Mapsize);
		_Map = _M;
		_Mapsize = _Newsize;
		return (_M + _Newsize / 4); }
	void _Setptr(_Mapptr _M, _Tptr _P)
		{*_M = _P; }
	_A allocator;
	iterator _First, _Last;
	_Mapptr _Map;
	size_type _Mapsize, _Size;
	};
		// deque TEMPLATE OPERATORS
template<class _Ty, class _A> inline
	bool operator==(const deque<_Ty, _A>& _X,
		const deque<_Ty, _A>& _Y)
	{return (_X.size() == _Y.size()
		&& equal(_X.begin(), _X.end(), _Y.begin())); }
template<class _Ty, class _A> inline
	bool operator!=(const deque<_Ty, _A>& _X,
		const deque<_Ty, _A>& _Y)
	{return (!(_X == _Y)); }
template<class _Ty, class _A> inline
	bool operator<(const deque<_Ty, _A>& _X,
		const deque<_Ty, _A>& _Y)
	{return (lexicographical_compare(_X.begin(), _X.end(),
		_Y.begin(), _Y.end())); }
template<class _Ty, class _A> inline
	bool operator<=(const deque<_Ty, _A>& _X,
		const deque<_Ty, _A>& _Y)
	{return (!(_Y < _X)); }
template<class _Ty, class _A> inline
	bool operator>(const deque<_Ty, _A>& _X,
		const deque<_Ty, _A>& _Y)
	{return (_Y < _X); }
template<class _Ty, class _A> inline
	bool operator>=(const deque<_Ty, _A>& _X,
		const deque<_Ty, _A>& _Y)
	{return (!(_X < _Y)); }
_STD_END
#ifdef  _MSC_VER
#pragma pack(pop)
#endif  /* _MSC_VER */

#endif /* _DEQUE_ */

/*
 * Copyright (c) 1995 by P.J. Plauger.  ALL RIGHTS RESERVED. 
 * Consult your license regarding permissions and restrictions.
 */

/*
 * This file is derived from software bearing the following
 * restrictions:
 *
 * 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.
 */