is_sorted.h

/***************************************************************************
 * include/stxxl/bits/common/is_sorted.h
 *
 * Part of the STXXL. See http://stxxl.sourceforge.net
 *
 * Copyright (C) 2002 Roman Dementiev <[email protected]>
 * Copyright (C) 2008 Andreas Beckmann <[email protected]>
 *
 * Distributed under the Boost Software License, Version 1.0.
 * (See accompanying file LICENSE_1_0.txt or copy at
 * http://www.boost.org/LICENSE_1_0.txt)
 **************************************************************************/

#ifndef STXXL_IS_SORTED_HEADER
#define STXXL_IS_SORTED_HEADER

#include <stxxl/bits/namespace.h>


__STXXL_BEGIN_NAMESPACE

template <class _ForwardIter>
bool is_sorted_helper(_ForwardIter __first, _ForwardIter __last)
{
 if (__first == __last)
 return true;

 _ForwardIter __next = __first;
 for (++__next; __next != __last; __first = __next, ++__next) {
 if (*__next < *__first)
 return false;
 }

 return true;
}

template <class _ForwardIter, class _StrictWeakOrdering>
bool is_sorted_helper(_ForwardIter __first, _ForwardIter __last,
 _StrictWeakOrdering __comp)
{
 if (__first == __last)
 return true;

 _ForwardIter __next = __first;
 for (++__next; __next != __last; __first = __next, ++__next) {
 if (__comp(*__next, *__first))
 return false;
 }

 return true;
}

template <class _ForwardIter>
bool is_sorted(_ForwardIter __first, _ForwardIter __last)
{
 return is_sorted_helper(__first, __last);
}

template <class _ForwardIter, class _StrictWeakOrdering>
bool is_sorted(_ForwardIter __first, _ForwardIter __last,
 _StrictWeakOrdering __comp)
{
 return is_sorted_helper(__first, __last, __comp);
}

__STXXL_END_NAMESPACE

#endif // !STXXL_IS_SORTED_HEADER