source: NonGTP/Boost/boost/pending/is_heap.hpp @ 857

//
//=======================================================================
// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
//
// 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)
//=======================================================================
//
#if __KCC
namespace std {

template <class RandomAccessIterator, class Distance>
bool __is_heap(RandomAccessIterator first, RandomAccessIterator last,
               Distance*)
{
  const Distance n = last - first;

  Distance parent = 0;
  for (Distance child = 1; child < n; ++child) {
    if (first[parent] < first[child]) 
      return false;
    if ((child & 1) == 0)
      ++parent;
  }
  return true;
}

template <class RandomAccessIterator>
inline bool is_heap(RandomAccessIterator first, RandomAccessIterator last)
{
  return __is_heap(first, last, distance_type(first));
}


template <class RandomAccessIterator, class Distance, class StrictWeakOrdering>
bool __is_heap(RandomAccessIterator first, RandomAccessIterator last,
               StrictWeakOrdering comp,
               Distance*)
{
  const Distance n = last - first;

  Distance parent = 0;
  for (Distance child = 1; child < n; ++child) {
    if (comp(first[parent], first[child]))
      return false;
    if ((child & 1) == 0)
      ++parent;
  }
  return true;
}

template <class RandomAccessIterator, class StrictWeakOrdering>
inline bool is_heap(RandomAccessIterator first, RandomAccessIterator last,
                    StrictWeakOrdering comp)
{
  return __is_heap(first, last, comp, distance_type(first));
}

}
#endif