// Iterators -*- C++ -*-
	
	// Copyright (C) 2001-2013 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) 1996-1998
	 * 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_iterator.h
	 *  This is an internal header file, included by other library headers.
	 *  Do not attempt to use it directly. @headername{iterator}
	 *
	 *  This file implements reverse_iterator, back_insert_iterator,
	 *  front_insert_iterator, insert_iterator, __normal_iterator, and their
	 *  supporting functions and overloaded operators.
	 */
	
	#ifndef _STL_ITERATOR_H
	#define _STL_ITERATOR_H 1
	
	#include <bits/cpp_type_traits.h>
	#include <ext/type_traits.h>
	#include <bits/move.h>
	
	namespace std _GLIBCXX_VISIBILITY(default)
	{
	_GLIBCXX_BEGIN_NAMESPACE_VERSION
	
	  /**
	   * @addtogroup iterators
	   * @{
	   */
	
	  // 24.4.1 Reverse iterators
	  /**
	   *  Bidirectional and random access iterators have corresponding reverse
	   *  %iterator adaptors that iterate through the data structure in the
	   *  opposite direction.  They have the same signatures as the corresponding
	   *  iterators.  The fundamental relation between a reverse %iterator and its
	   *  corresponding %iterator @c i is established by the identity:
	   *  @code
	   *      &*(reverse_iterator(i)) == &*(i - 1)
	   *  @endcode
	   *
	   *  <em>This mapping is dictated by the fact that while there is always a
	   *  pointer past the end of an array, there might not be a valid pointer
	   *  before the beginning of an array.</em> [24.4.1]/1,2
	   *
	   *  Reverse iterators can be tricky and surprising at first.  Their
	   *  semantics make sense, however, and the trickiness is a side effect of
	   *  the requirement that the iterators must be safe.
	  */
	  template<typename _Iterator>
	    class reverse_iterator
	    : public iterator<typename iterator_traits<_Iterator>::iterator_category,
			      typename iterator_traits<_Iterator>::value_type,
			      typename iterator_traits<_Iterator>::difference_type,
			      typename iterator_traits<_Iterator>::pointer,
	                      typename iterator_traits<_Iterator>::reference>
	    {
	    protected:
	      _Iterator current;
	
	      typedef iterator_traits<_Iterator>		__traits_type;
	
	    public:
	      typedef _Iterator					iterator_type;
	      typedef typename __traits_type::difference_type	difference_type;
	      typedef typename __traits_type::pointer		pointer;
	      typedef typename __traits_type::reference		reference;
	
	      /**
	       *  The default constructor value-initializes member @p current.
	       *  If it is a pointer, that means it is zero-initialized.
	      */
	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
	      // 235 No specification of default ctor for reverse_iterator
	      reverse_iterator() : current() { }
	
	      /**
	       *  This %iterator will move in the opposite direction that @p x does.
	      */
	      explicit
	      reverse_iterator(iterator_type __x) : current(__x) { }
	
	      /**
	       *  The copy constructor is normal.
	      */
	      reverse_iterator(const reverse_iterator& __x)
	      : current(__x.current) { }
	
	      /**
	       *  A %reverse_iterator across other types can be copied if the
	       *  underlying %iterator can be converted to the type of @c current.
	      */
	      template<typename _Iter>
	        reverse_iterator(const reverse_iterator<_Iter>& __x)
		: current(__x.base()) { }
	
	      /**
	       *  @return  @c current, the %iterator used for underlying work.
	      */
	      iterator_type
	      base() const
	      { return current; }
	
	      /**
	       *  @return  A reference to the value at @c --current
	       *
	       *  This requires that @c --current is dereferenceable.
	       *
	       *  @warning This implementation requires that for an iterator of the
	       *           underlying iterator type, @c x, a reference obtained by
	       *           @c *x remains valid after @c x has been modified or
	       *           destroyed. This is a bug: http://gcc.gnu.org/PR51823
	      */
	      reference
	      operator*() const
	      {
		_Iterator __tmp = current;
		return *--__tmp;
	      }
	
	      /**
	       *  @return  A pointer to the value at @c --current
	       *
	       *  This requires that @c --current is dereferenceable.
	      */
	      pointer
	      operator->() const
	      { return &(operator*()); }
	
	      /**
	       *  @return  @c *this
	       *
	       *  Decrements the underlying iterator.
	      */
	      reverse_iterator&
	      operator++()
	      {
		--current;
		return *this;
	      }
	
	      /**
	       *  @return  The original value of @c *this
	       *
	       *  Decrements the underlying iterator.
	      */
	      reverse_iterator
	      operator++(int)
	      {
		reverse_iterator __tmp = *this;
		--current;
		return __tmp;
	      }
	
	      /**
	       *  @return  @c *this
	       *
	       *  Increments the underlying iterator.
	      */
	      reverse_iterator&
	      operator--()
	      {
		++current;
		return *this;
	      }
	
	      /**
	       *  @return  A reverse_iterator with the previous value of @c *this
	       *
	       *  Increments the underlying iterator.
	      */
	      reverse_iterator
	      operator--(int)
	      {
		reverse_iterator __tmp = *this;
		++current;
		return __tmp;
	      }
	
	      /**
	       *  @return  A reverse_iterator that refers to @c current - @a __n
	       *
	       *  The underlying iterator must be a Random Access Iterator.
	      */
	      reverse_iterator
	      operator+(difference_type __n) const
	      { return reverse_iterator(current - __n); }
	
	      /**
	       *  @return  *this
	       *
	       *  Moves the underlying iterator backwards @a __n steps.
	       *  The underlying iterator must be a Random Access Iterator.
	      */
	      reverse_iterator&
	      operator+=(difference_type __n)
	      {
		current -= __n;
		return *this;
	      }
	
	      /**
	       *  @return  A reverse_iterator that refers to @c current - @a __n
	       *
	       *  The underlying iterator must be a Random Access Iterator.
	      */
	      reverse_iterator
	      operator-(difference_type __n) const
	      { return reverse_iterator(current + __n); }
	
	      /**
	       *  @return  *this
	       *
	       *  Moves the underlying iterator forwards @a __n steps.
	       *  The underlying iterator must be a Random Access Iterator.
	      */
	      reverse_iterator&
	      operator-=(difference_type __n)
	      {
		current += __n;
		return *this;
	      }
	
	      /**
	       *  @return  The value at @c current - @a __n - 1
	       *
	       *  The underlying iterator must be a Random Access Iterator.
	      */
	      reference
	      operator[](difference_type __n) const
	      { return *(*this + __n); }
	    };
	
	  //@{
	  /**
	   *  @param  __x  A %reverse_iterator.
	   *  @param  __y  A %reverse_iterator.
	   *  @return  A simple bool.
	   *
	   *  Reverse iterators forward many operations to their underlying base()
	   *  iterators.  Others are implemented in terms of one another.
	   *
	  */
	  template<typename _Iterator>
	    inline bool
	    operator==(const reverse_iterator<_Iterator>& __x,
		       const reverse_iterator<_Iterator>& __y)
	    { return __x.base() == __y.base(); }
	
	  template<typename _Iterator>
	    inline bool
	    operator<(const reverse_iterator<_Iterator>& __x,
		      const reverse_iterator<_Iterator>& __y)
	    { return __y.base() < __x.base(); }
	
	  template<typename _Iterator>
	    inline bool
	    operator!=(const reverse_iterator<_Iterator>& __x,
		       const reverse_iterator<_Iterator>& __y)
	    { return !(__x == __y); }
	
	  template<typename _Iterator>
	    inline bool
	    operator>(const reverse_iterator<_Iterator>& __x,
		      const reverse_iterator<_Iterator>& __y)
	    { return __y < __x; }
	
	  template<typename _Iterator>
	    inline bool
	    operator<=(const reverse_iterator<_Iterator>& __x,
		       const reverse_iterator<_Iterator>& __y)
	    { return !(__y < __x); }
	
	  template<typename _Iterator>
	    inline bool
	    operator>=(const reverse_iterator<_Iterator>& __x,
		       const reverse_iterator<_Iterator>& __y)
	    { return !(__x < __y); }
	
	  template<typename _Iterator>
	    inline typename reverse_iterator<_Iterator>::difference_type
	    operator-(const reverse_iterator<_Iterator>& __x,
		      const reverse_iterator<_Iterator>& __y)
	    { return __y.base() - __x.base(); }
	
	  template<typename _Iterator>
	    inline reverse_iterator<_Iterator>
	    operator+(typename reverse_iterator<_Iterator>::difference_type __n,
		      const reverse_iterator<_Iterator>& __x)
	    { return reverse_iterator<_Iterator>(__x.base() - __n); }
	
	  // _GLIBCXX_RESOLVE_LIB_DEFECTS
	  // DR 280. Comparison of reverse_iterator to const reverse_iterator.
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator==(const reverse_iterator<_IteratorL>& __x,
		       const reverse_iterator<_IteratorR>& __y)
	    { return __x.base() == __y.base(); }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator<(const reverse_iterator<_IteratorL>& __x,
		      const reverse_iterator<_IteratorR>& __y)
	    { return __y.base() < __x.base(); }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator!=(const reverse_iterator<_IteratorL>& __x,
		       const reverse_iterator<_IteratorR>& __y)
	    { return !(__x == __y); }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator>(const reverse_iterator<_IteratorL>& __x,
		      const reverse_iterator<_IteratorR>& __y)
	    { return __y < __x; }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator<=(const reverse_iterator<_IteratorL>& __x,
		       const reverse_iterator<_IteratorR>& __y)
	    { return !(__y < __x); }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator>=(const reverse_iterator<_IteratorL>& __x,
		       const reverse_iterator<_IteratorR>& __y)
	    { return !(__x < __y); }
	
	  template<typename _IteratorL, typename _IteratorR>
	#if __cplusplus >= 201103L
	    // DR 685.
	    inline auto
	    operator-(const reverse_iterator<_IteratorL>& __x,
		      const reverse_iterator<_IteratorR>& __y)
	    -> decltype(__y.base() - __x.base())
	#else
	    inline typename reverse_iterator<_IteratorL>::difference_type
	    operator-(const reverse_iterator<_IteratorL>& __x,
		      const reverse_iterator<_IteratorR>& __y)
	#endif
	    { return __y.base() - __x.base(); }
	  //@}
	
	  // 24.4.2.2.1 back_insert_iterator
	  /**
	   *  @brief  Turns assignment into insertion.
	   *
	   *  These are output iterators, constructed from a container-of-T.
	   *  Assigning a T to the iterator appends it to the container using
	   *  push_back.
	   *
	   *  Tip:  Using the back_inserter function to create these iterators can
	   *  save typing.
	  */
	  template<typename _Container>
	    class back_insert_iterator
	    : public iterator<output_iterator_tag, void, void, void, void>
	    {
	    protected:
	      _Container* container;
	
	    public:
	      /// A nested typedef for the type of whatever container you used.
	      typedef _Container          container_type;
	
	      /// The only way to create this %iterator is with a container.
	      explicit
	      back_insert_iterator(_Container& __x) : container(&__x) { }
	
	      /**
	       *  @param  __value  An instance of whatever type
	       *                 container_type::const_reference is; presumably a
	       *                 reference-to-const T for container<T>.
	       *  @return  This %iterator, for chained operations.
	       *
	       *  This kind of %iterator doesn't really have a @a position in the
	       *  container (you can think of the position as being permanently at
	       *  the end, if you like).  Assigning a value to the %iterator will
	       *  always append the value to the end of the container.
	      */
	#if __cplusplus < 201103L
	      back_insert_iterator&
	      operator=(typename _Container::const_reference __value)
	      {
		container->push_back(__value);
		return *this;
	      }
	#else
	      back_insert_iterator&
	      operator=(const typename _Container::value_type& __value)
	      {
		container->push_back(__value);
		return *this;
	      }
	
	      back_insert_iterator&
	      operator=(typename _Container::value_type&& __value)
	      {
		container->push_back(std::move(__value));
		return *this;
	      }
	#endif
	
	      /// Simply returns *this.
	      back_insert_iterator&
	      operator*()
	      { return *this; }
	
	      /// Simply returns *this.  (This %iterator does not @a move.)
	      back_insert_iterator&
	      operator++()
	      { return *this; }
	
	      /// Simply returns *this.  (This %iterator does not @a move.)
	      back_insert_iterator
	      operator++(int)
	      { return *this; }
	    };
	
	  /**
	   *  @param  __x  A container of arbitrary type.
	   *  @return  An instance of back_insert_iterator working on @p __x.
	   *
	   *  This wrapper function helps in creating back_insert_iterator instances.
	   *  Typing the name of the %iterator requires knowing the precise full
	   *  type of the container, which can be tedious and impedes generic
	   *  programming.  Using this function lets you take advantage of automatic
	   *  template parameter deduction, making the compiler match the correct
	   *  types for you.
	  */
	  template<typename _Container>
	    inline back_insert_iterator<_Container>
	    back_inserter(_Container& __x)
	    { return back_insert_iterator<_Container>(__x); }
	
	  /**
	   *  @brief  Turns assignment into insertion.
	   *
	   *  These are output iterators, constructed from a container-of-T.
	   *  Assigning a T to the iterator prepends it to the container using
	   *  push_front.
	   *
	   *  Tip:  Using the front_inserter function to create these iterators can
	   *  save typing.
	  */
	  template<typename _Container>
	    class front_insert_iterator
	    : public iterator<output_iterator_tag, void, void, void, void>
	    {
	    protected:
	      _Container* container;
	
	    public:
	      /// A nested typedef for the type of whatever container you used.
	      typedef _Container          container_type;
	
	      /// The only way to create this %iterator is with a container.
	      explicit front_insert_iterator(_Container& __x) : container(&__x) { }
	
	      /**
	       *  @param  __value  An instance of whatever type
	       *                 container_type::const_reference is; presumably a
	       *                 reference-to-const T for container<T>.
	       *  @return  This %iterator, for chained operations.
	       *
	       *  This kind of %iterator doesn't really have a @a position in the
	       *  container (you can think of the position as being permanently at
	       *  the front, if you like).  Assigning a value to the %iterator will
	       *  always prepend the value to the front of the container.
	      */
	#if __cplusplus < 201103L
	      front_insert_iterator&
	      operator=(typename _Container::const_reference __value)
	      {
		container->push_front(__value);
		return *this;
	      }
	#else
	      front_insert_iterator&
	      operator=(const typename _Container::value_type& __value)
	      {
		container->push_front(__value);
		return *this;
	      }
	
	      front_insert_iterator&
	      operator=(typename _Container::value_type&& __value)
	      {
		container->push_front(std::move(__value));
		return *this;
	      }
	#endif
	
	      /// Simply returns *this.
	      front_insert_iterator&
	      operator*()
	      { return *this; }
	
	      /// Simply returns *this.  (This %iterator does not @a move.)
	      front_insert_iterator&
	      operator++()
	      { return *this; }
	
	      /// Simply returns *this.  (This %iterator does not @a move.)
	      front_insert_iterator
	      operator++(int)
	      { return *this; }
	    };
	
	  /**
	   *  @param  __x  A container of arbitrary type.
	   *  @return  An instance of front_insert_iterator working on @p x.
	   *
	   *  This wrapper function helps in creating front_insert_iterator instances.
	   *  Typing the name of the %iterator requires knowing the precise full
	   *  type of the container, which can be tedious and impedes generic
	   *  programming.  Using this function lets you take advantage of automatic
	   *  template parameter deduction, making the compiler match the correct
	   *  types for you.
	  */
	  template<typename _Container>
	    inline front_insert_iterator<_Container>
	    front_inserter(_Container& __x)
	    { return front_insert_iterator<_Container>(__x); }
	
	  /**
	   *  @brief  Turns assignment into insertion.
	   *
	   *  These are output iterators, constructed from a container-of-T.
	   *  Assigning a T to the iterator inserts it in the container at the
	   *  %iterator's position, rather than overwriting the value at that
	   *  position.
	   *
	   *  (Sequences will actually insert a @e copy of the value before the
	   *  %iterator's position.)
	   *
	   *  Tip:  Using the inserter function to create these iterators can
	   *  save typing.
	  */
	  template<typename _Container>
	    class insert_iterator
	    : public iterator<output_iterator_tag, void, void, void, void>
	    {
	    protected:
	      _Container* container;
	      typename _Container::iterator iter;
	
	    public:
	      /// A nested typedef for the type of whatever container you used.
	      typedef _Container          container_type;
	
	      /**
	       *  The only way to create this %iterator is with a container and an
	       *  initial position (a normal %iterator into the container).
	      */
	      insert_iterator(_Container& __x, typename _Container::iterator __i)
	      : container(&__x), iter(__i) {}
	
	      /**
	       *  @param  __value  An instance of whatever type
	       *                 container_type::const_reference is; presumably a
	       *                 reference-to-const T for container<T>.
	       *  @return  This %iterator, for chained operations.
	       *
	       *  This kind of %iterator maintains its own position in the
	       *  container.  Assigning a value to the %iterator will insert the
	       *  value into the container at the place before the %iterator.
	       *
	       *  The position is maintained such that subsequent assignments will
	       *  insert values immediately after one another.  For example,
	       *  @code
	       *     // vector v contains A and Z
	       *
	       *     insert_iterator i (v, ++v.begin());
	       *     i = 1;
	       *     i = 2;
	       *     i = 3;
	       *
	       *     // vector v contains A, 1, 2, 3, and Z
	       *  @endcode
	      */
	#if __cplusplus < 201103L
	      insert_iterator&
	      operator=(typename _Container::const_reference __value)
	      {
		iter = container->insert(iter, __value);
		++iter;
		return *this;
	      }
	#else
	      insert_iterator&
	      operator=(const typename _Container::value_type& __value)
	      {
		iter = container->insert(iter, __value);
		++iter;
		return *this;
	      }
	
	      insert_iterator&
	      operator=(typename _Container::value_type&& __value)
	      {
		iter = container->insert(iter, std::move(__value));
		++iter;
		return *this;
	      }
	#endif
	
	      /// Simply returns *this.
	      insert_iterator&
	      operator*()
	      { return *this; }
	
	      /// Simply returns *this.  (This %iterator does not @a move.)
	      insert_iterator&
	      operator++()
	      { return *this; }
	
	      /// Simply returns *this.  (This %iterator does not @a move.)
	      insert_iterator&
	      operator++(int)
	      { return *this; }
	    };
	
	  /**
	   *  @param __x  A container of arbitrary type.
	   *  @return  An instance of insert_iterator working on @p __x.
	   *
	   *  This wrapper function helps in creating insert_iterator instances.
	   *  Typing the name of the %iterator requires knowing the precise full
	   *  type of the container, which can be tedious and impedes generic
	   *  programming.  Using this function lets you take advantage of automatic
	   *  template parameter deduction, making the compiler match the correct
	   *  types for you.
	  */
	  template<typename _Container, typename _Iterator>
	    inline insert_iterator<_Container>
	    inserter(_Container& __x, _Iterator __i)
	    {
	      return insert_iterator<_Container>(__x,
						 typename _Container::iterator(__i));
	    }
	
	  // @} group iterators
	
	_GLIBCXX_END_NAMESPACE_VERSION
	} // namespace
	
	namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
	{
	_GLIBCXX_BEGIN_NAMESPACE_VERSION
	
	  // This iterator adapter is @a normal in the sense that it does not
	  // change the semantics of any of the operators of its iterator
	  // parameter.  Its primary purpose is to convert an iterator that is
	  // not a class, e.g. a pointer, into an iterator that is a class.
	  // The _Container parameter exists solely so that different containers
	  // using this template can instantiate different types, even if the
	  // _Iterator parameter is the same.
	  using std::iterator_traits;
	  using std::iterator;
	  template<typename _Iterator, typename _Container>
	    class __normal_iterator
	    {
	    protected:
	      _Iterator _M_current;
	
	      typedef iterator_traits<_Iterator>		__traits_type;
	
	    public:
	      typedef _Iterator					iterator_type;
	      typedef typename __traits_type::iterator_category iterator_category;
	      typedef typename __traits_type::value_type  	value_type;
	      typedef typename __traits_type::difference_type 	difference_type;
	      typedef typename __traits_type::reference 	reference;
	      typedef typename __traits_type::pointer   	pointer;
	
	      _GLIBCXX_CONSTEXPR __normal_iterator() : _M_current(_Iterator()) { }
	
	      explicit
	      __normal_iterator(const _Iterator& __i) : _M_current(__i) { }
	
	      // Allow iterator to const_iterator conversion
	      template<typename _Iter>
	        __normal_iterator(const __normal_iterator<_Iter,
				  typename __enable_if<
	      	       (std::__are_same<_Iter, typename _Container::pointer>::__value),
			      _Container>::__type>& __i)
	        : _M_current(__i.base()) { }
	
	      // Forward iterator requirements
	      reference
	      operator*() const
	      { return *_M_current; }
	
	      pointer
	      operator->() const
	      { return _M_current; }
	
	      __normal_iterator&
	      operator++()
	      {
		++_M_current;
		return *this;
	      }
	
	      __normal_iterator
	      operator++(int)
	      { return __normal_iterator(_M_current++); }
	
	      // Bidirectional iterator requirements
	      __normal_iterator&
	      operator--()
	      {
		--_M_current;
		return *this;
	      }
	
	      __normal_iterator
	      operator--(int)
	      { return __normal_iterator(_M_current--); }
	
	      // Random access iterator requirements
	      reference
	      operator[](const difference_type& __n) const
	      { return _M_current[__n]; }
	
	      __normal_iterator&
	      operator+=(const difference_type& __n)
	      { _M_current += __n; return *this; }
	
	      __normal_iterator
	      operator+(const difference_type& __n) const
	      { return __normal_iterator(_M_current + __n); }
	
	      __normal_iterator&
	      operator-=(const difference_type& __n)
	      { _M_current -= __n; return *this; }
	
	      __normal_iterator
	      operator-(const difference_type& __n) const
	      { return __normal_iterator(_M_current - __n); }
	
	      const _Iterator&
	      base() const
	      { return _M_current; }
	    };
	
	  // Note: In what follows, the left- and right-hand-side iterators are
	  // allowed to vary in types (conceptually in cv-qualification) so that
	  // comparison between cv-qualified and non-cv-qualified iterators be
	  // valid.  However, the greedy and unfriendly operators in std::rel_ops
	  // will make overload resolution ambiguous (when in scope) if we don't
	  // provide overloads whose operands are of the same type.  Can someone
	  // remind me what generic programming is about? -- Gaby
	
	  // Forward iterator requirements
	  template<typename _IteratorL, typename _IteratorR, typename _Container>
	    inline bool
	    operator==(const __normal_iterator<_IteratorL, _Container>& __lhs,
		       const __normal_iterator<_IteratorR, _Container>& __rhs)
	    { return __lhs.base() == __rhs.base(); }
	
	  template<typename _Iterator, typename _Container>
	    inline bool
	    operator==(const __normal_iterator<_Iterator, _Container>& __lhs,
		       const __normal_iterator<_Iterator, _Container>& __rhs)
	    { return __lhs.base() == __rhs.base(); }
	
	  template<typename _IteratorL, typename _IteratorR, typename _Container>
	    inline bool
	    operator!=(const __normal_iterator<_IteratorL, _Container>& __lhs,
		       const __normal_iterator<_IteratorR, _Container>& __rhs)
	    { return __lhs.base() != __rhs.base(); }
	
	  template<typename _Iterator, typename _Container>
	    inline bool
	    operator!=(const __normal_iterator<_Iterator, _Container>& __lhs,
		       const __normal_iterator<_Iterator, _Container>& __rhs)
	    { return __lhs.base() != __rhs.base(); }
	
	  // Random access iterator requirements
	  template<typename _IteratorL, typename _IteratorR, typename _Container>
	    inline bool
	    operator<(const __normal_iterator<_IteratorL, _Container>& __lhs,
		      const __normal_iterator<_IteratorR, _Container>& __rhs)
	    { return __lhs.base() < __rhs.base(); }
	
	  template<typename _Iterator, typename _Container>
	    inline bool
	    operator<(const __normal_iterator<_Iterator, _Container>& __lhs,
		      const __normal_iterator<_Iterator, _Container>& __rhs)
	    { return __lhs.base() < __rhs.base(); }
	
	  template<typename _IteratorL, typename _IteratorR, typename _Container>
	    inline bool
	    operator>(const __normal_iterator<_IteratorL, _Container>& __lhs,
		      const __normal_iterator<_IteratorR, _Container>& __rhs)
	    { return __lhs.base() > __rhs.base(); }
	
	  template<typename _Iterator, typename _Container>
	    inline bool
	    operator>(const __normal_iterator<_Iterator, _Container>& __lhs,
		      const __normal_iterator<_Iterator, _Container>& __rhs)
	    { return __lhs.base() > __rhs.base(); }
	
	  template<typename _IteratorL, typename _IteratorR, typename _Container>
	    inline bool
	    operator<=(const __normal_iterator<_IteratorL, _Container>& __lhs,
		       const __normal_iterator<_IteratorR, _Container>& __rhs)
	    { return __lhs.base() <= __rhs.base(); }
	
	  template<typename _Iterator, typename _Container>
	    inline bool
	    operator<=(const __normal_iterator<_Iterator, _Container>& __lhs,
		       const __normal_iterator<_Iterator, _Container>& __rhs)
	    { return __lhs.base() <= __rhs.base(); }
	
	  template<typename _IteratorL, typename _IteratorR, typename _Container>
	    inline bool
	    operator>=(const __normal_iterator<_IteratorL, _Container>& __lhs,
		       const __normal_iterator<_IteratorR, _Container>& __rhs)
	    { return __lhs.base() >= __rhs.base(); }
	
	  template<typename _Iterator, typename _Container>
	    inline bool
	    operator>=(const __normal_iterator<_Iterator, _Container>& __lhs,
		       const __normal_iterator<_Iterator, _Container>& __rhs)
	    { return __lhs.base() >= __rhs.base(); }
	
	  // _GLIBCXX_RESOLVE_LIB_DEFECTS
	  // According to the resolution of DR179 not only the various comparison
	  // operators but also operator- must accept mixed iterator/const_iterator
	  // parameters.
	  template<typename _IteratorL, typename _IteratorR, typename _Container>
	#if __cplusplus >= 201103L
	    // DR 685.
	    inline auto
	    operator-(const __normal_iterator<_IteratorL, _Container>& __lhs,
		      const __normal_iterator<_IteratorR, _Container>& __rhs)
	    -> decltype(__lhs.base() - __rhs.base())
	#else
	    inline typename __normal_iterator<_IteratorL, _Container>::difference_type
	    operator-(const __normal_iterator<_IteratorL, _Container>& __lhs,
		      const __normal_iterator<_IteratorR, _Container>& __rhs)
	#endif
	    { return __lhs.base() - __rhs.base(); }
	
	  template<typename _Iterator, typename _Container>
	    inline typename __normal_iterator<_Iterator, _Container>::difference_type
	    operator-(const __normal_iterator<_Iterator, _Container>& __lhs,
		      const __normal_iterator<_Iterator, _Container>& __rhs)
	    { return __lhs.base() - __rhs.base(); }
	
	  template<typename _Iterator, typename _Container>
	    inline __normal_iterator<_Iterator, _Container>
	    operator+(typename __normal_iterator<_Iterator, _Container>::difference_type
		      __n, const __normal_iterator<_Iterator, _Container>& __i)
	    { return __normal_iterator<_Iterator, _Container>(__i.base() + __n); }
	
	_GLIBCXX_END_NAMESPACE_VERSION
	} // namespace
	
	#if __cplusplus >= 201103L
	
	namespace std _GLIBCXX_VISIBILITY(default)
	{
	_GLIBCXX_BEGIN_NAMESPACE_VERSION
	
	  /**
	   * @addtogroup iterators
	   * @{
	   */
	
	  // 24.4.3  Move iterators
	  /**
	   *  Class template move_iterator is an iterator adapter with the same
	   *  behavior as the underlying iterator except that its dereference
	   *  operator implicitly converts the value returned by the underlying
	   *  iterator's dereference operator to an rvalue reference.  Some
	   *  generic algorithms can be called with move iterators to replace
	   *  copying with moving.
	   */
	  template<typename _Iterator>
	    class move_iterator
	    {
	    protected:
	      _Iterator _M_current;
	
	      typedef iterator_traits<_Iterator>		__traits_type;
	
	    public:
	      typedef _Iterator					iterator_type;
	      typedef typename __traits_type::iterator_category iterator_category;
	      typedef typename __traits_type::value_type  	value_type;
	      typedef typename __traits_type::difference_type	difference_type;
	      // NB: DR 680.
	      typedef _Iterator					pointer;
	      typedef value_type&&				reference;
	
	      move_iterator()
	      : _M_current() { }
	
	      explicit
	      move_iterator(iterator_type __i)
	      : _M_current(__i) { }
	
	      template<typename _Iter>
		move_iterator(const move_iterator<_Iter>& __i)
		: _M_current(__i.base()) { }
	
	      iterator_type
	      base() const
	      { return _M_current; }
	
	      reference
	      operator*() const
	      { return std::move(*_M_current); }
	
	      pointer
	      operator->() const
	      { return _M_current; }
	
	      move_iterator&
	      operator++()
	      {
		++_M_current;
		return *this;
	      }
	
	      move_iterator
	      operator++(int)
	      {
		move_iterator __tmp = *this;
		++_M_current;
		return __tmp;
	      }
	
	      move_iterator&
	      operator--()
	      {
		--_M_current;
		return *this;
	      }
	
	      move_iterator
	      operator--(int)
	      {
		move_iterator __tmp = *this;
		--_M_current;
		return __tmp;
	      }
	
	      move_iterator
	      operator+(difference_type __n) const
	      { return move_iterator(_M_current + __n); }
	
	      move_iterator&
	      operator+=(difference_type __n)
	      {
		_M_current += __n;
		return *this;
	      }
	
	      move_iterator
	      operator-(difference_type __n) const
	      { return move_iterator(_M_current - __n); }
	    
	      move_iterator&
	      operator-=(difference_type __n)
	      { 
		_M_current -= __n;
		return *this;
	      }
	
	      reference
	      operator[](difference_type __n) const
	      { return std::move(_M_current[__n]); }
	    };
	
	  // Note: See __normal_iterator operators note from Gaby to understand
	  // why there are always 2 versions for most of the move_iterator
	  // operators.
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator==(const move_iterator<_IteratorL>& __x,
		       const move_iterator<_IteratorR>& __y)
	    { return __x.base() == __y.base(); }
	
	  template<typename _Iterator>
	    inline bool
	    operator==(const move_iterator<_Iterator>& __x,
		       const move_iterator<_Iterator>& __y)
	    { return __x.base() == __y.base(); }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator!=(const move_iterator<_IteratorL>& __x,
		       const move_iterator<_IteratorR>& __y)
	    { return !(__x == __y); }
	
	  template<typename _Iterator>
	    inline bool
	    operator!=(const move_iterator<_Iterator>& __x,
		       const move_iterator<_Iterator>& __y)
	    { return !(__x == __y); }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator<(const move_iterator<_IteratorL>& __x,
		      const move_iterator<_IteratorR>& __y)
	    { return __x.base() < __y.base(); }
	
	  template<typename _Iterator>
	    inline bool
	    operator<(const move_iterator<_Iterator>& __x,
		      const move_iterator<_Iterator>& __y)
	    { return __x.base() < __y.base(); }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator<=(const move_iterator<_IteratorL>& __x,
		       const move_iterator<_IteratorR>& __y)
	    { return !(__y < __x); }
	
	  template<typename _Iterator>
	    inline bool
	    operator<=(const move_iterator<_Iterator>& __x,
		       const move_iterator<_Iterator>& __y)
	    { return !(__y < __x); }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator>(const move_iterator<_IteratorL>& __x,
		      const move_iterator<_IteratorR>& __y)
	    { return __y < __x; }
	
	  template<typename _Iterator>
	    inline bool
	    operator>(const move_iterator<_Iterator>& __x,
		      const move_iterator<_Iterator>& __y)
	    { return __y < __x; }
	
	  template<typename _IteratorL, typename _IteratorR>
	    inline bool
	    operator>=(const move_iterator<_IteratorL>& __x,
		       const move_iterator<_IteratorR>& __y)
	    { return !(__x < __y); }
	
	  template<typename _Iterator>
	    inline bool
	    operator>=(const move_iterator<_Iterator>& __x,
		       const move_iterator<_Iterator>& __y)
	    { return !(__x < __y); }
	
	  // DR 685.
	  template<typename _IteratorL, typename _IteratorR>
	    inline auto
	    operator-(const move_iterator<_IteratorL>& __x,
		      const move_iterator<_IteratorR>& __y)
	    -> decltype(__x.base() - __y.base())
	    { return __x.base() - __y.base(); }
	
	  template<typename _Iterator>
	    inline auto
	    operator-(const move_iterator<_Iterator>& __x,
		      const move_iterator<_Iterator>& __y)
	    -> decltype(__x.base() - __y.base())
	    { return __x.base() - __y.base(); }
	
	  template<typename _Iterator>
	    inline move_iterator<_Iterator>
	    operator+(typename move_iterator<_Iterator>::difference_type __n,
		      const move_iterator<_Iterator>& __x)
	    { return __x + __n; }
	
	  template<typename _Iterator>
	    inline move_iterator<_Iterator>
	    make_move_iterator(_Iterator __i)
	    { return move_iterator<_Iterator>(__i); }
	
	  template<typename _Iterator, typename _ReturnType
	    = typename conditional<__move_if_noexcept_cond
	      <typename iterator_traits<_Iterator>::value_type>::value,
	                _Iterator, move_iterator<_Iterator>>::type>
	    inline _ReturnType
	    __make_move_if_noexcept_iterator(_Iterator __i)
	    { return _ReturnType(__i); }
	
	  // @} group iterators
	
	_GLIBCXX_END_NAMESPACE_VERSION
	} // namespace
	
	#define _GLIBCXX_MAKE_MOVE_ITERATOR(_Iter) std::make_move_iterator(_Iter)
	#define _GLIBCXX_MAKE_MOVE_IF_NOEXCEPT_ITERATOR(_Iter) \
	  std::__make_move_if_noexcept_iterator(_Iter)
	#else
	#define _GLIBCXX_MAKE_MOVE_ITERATOR(_Iter) (_Iter)
	#define _GLIBCXX_MAKE_MOVE_IF_NOEXCEPT_ITERATOR(_Iter) (_Iter)
	#endif // C++11
	
	#endif