is_heap.hpp

CGAL is a collaborative effort of several sites in Europe and Israel. The goal is to make the most i

//
//=======================================================================
// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
//
// This file is part of the Generic Graph Component Library
//
// You should have received a copy of the License Agreement for the
// Generic Graph Component Library along with the software;  see the
// file LICENSE.  If not, contact Office of Research, University of Notre
// Dame, Notre Dame, IN  46556.
//
// Permission to modify the code and to distribute modified code is
// granted, provided the text of this NOTICE is retained, a notice that
// the code was modified is included with the above COPYRIGHT NOTICE and
// with the COPYRIGHT NOTICE in the LICENSE file, and that the LICENSE
// file is distributed with the modified code.
//
// LICENSOR MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.
// By way of example, but not limitation, Licensor MAKES NO
// REPRESENTATIONS OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY
// PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED SOFTWARE COMPONENTS
// OR DOCUMENTATION WILL NOT INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS
// OR OTHER RIGHTS.
//=======================================================================
//
#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