// Heap implementation -*- C++ -*-
-// Copyright (C) 2001 Free Software Foundation, Inc.
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+// 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 2, or (at your option)
+// 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,
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
-// You should have received a copy of the GNU General Public License along
-// with this library; see the file COPYING. If not, write to the Free
-// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
-// USA.
+// 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.
-// As a special exception, you may use this file as part of a free software
-// library without restriction. Specifically, if other files instantiate
-// templates or use macros or inline functions from this file, or you compile
-// this file and link it with other files to produce an executable, this
-// file does not by itself cause the resulting executable to be covered by
-// the GNU General Public License. This exception does not however
-// invalidate any other reasons why the executable file might be covered by
-// the GNU General Public License.
+// 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/>.
/*
*
* You should not attempt to use it directly.
*/
-#ifndef _CPP_BITS_STL_HEAP_H
-#define _CPP_BITS_STL_HEAP_H 1
+#ifndef _STL_HEAP_H
+#define _STL_HEAP_H 1
-namespace std
-{
+#include <debug/debug.h>
+#include <bits/move.h>
- // Heap-manipulation functions: push_heap, pop_heap, make_heap, sort_heap.
+_GLIBCXX_BEGIN_NAMESPACE(std)
+
+ /**
+ * @defgroup heap_algorithms Heap Algorithms
+ * @ingroup sorting_algorithms
+ */
+
+ template<typename _RandomAccessIterator, typename _Distance>
+ _Distance
+ __is_heap_until(_RandomAccessIterator __first, _Distance __n)
+ {
+ _Distance __parent = 0;
+ for (_Distance __child = 1; __child < __n; ++__child)
+ {
+ if (__first[__parent] < __first[__child])
+ return __child;
+ if ((__child & 1) == 0)
+ ++__parent;
+ }
+ return __n;
+ }
+
+ template<typename _RandomAccessIterator, typename _Distance,
+ typename _Compare>
+ _Distance
+ __is_heap_until(_RandomAccessIterator __first, _Distance __n,
+ _Compare __comp)
+ {
+ _Distance __parent = 0;
+ for (_Distance __child = 1; __child < __n; ++__child)
+ {
+ if (__comp(__first[__parent], __first[__child]))
+ return __child;
+ if ((__child & 1) == 0)
+ ++__parent;
+ }
+ return __n;
+ }
+
+ // __is_heap, a predicate testing whether or not a range is a heap.
+ // This function is an extension, not part of the C++ standard.
+ template<typename _RandomAccessIterator, typename _Distance>
+ inline bool
+ __is_heap(_RandomAccessIterator __first, _Distance __n)
+ { return std::__is_heap_until(__first, __n) == __n; }
+
+ template<typename _RandomAccessIterator, typename _Compare,
+ typename _Distance>
+ inline bool
+ __is_heap(_RandomAccessIterator __first, _Compare __comp, _Distance __n)
+ { return std::__is_heap_until(__first, __n, __comp) == __n; }
+
+ template<typename _RandomAccessIterator>
+ inline bool
+ __is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
+ { return std::__is_heap(__first, std::distance(__first, __last)); }
+
+ template<typename _RandomAccessIterator, typename _Compare>
+ inline bool
+ __is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
+ _Compare __comp)
+ { return std::__is_heap(__first, __comp, std::distance(__first, __last)); }
+
+ // Heap-manipulation functions: push_heap, pop_heap, make_heap, sort_heap,
+ // + is_heap and is_heap_until in C++0x.
template<typename _RandomAccessIterator, typename _Distance, typename _Tp>
- void
+ void
__push_heap(_RandomAccessIterator __first,
_Distance __holeIndex, _Distance __topIndex, _Tp __value)
{
_Distance __parent = (__holeIndex - 1) / 2;
- while (__holeIndex > __topIndex && *(__first + __parent) < __value) {
- *(__first + __holeIndex) = *(__first + __parent);
- __holeIndex = __parent;
- __parent = (__holeIndex - 1) / 2;
- }
- *(__first + __holeIndex) = __value;
+ while (__holeIndex > __topIndex && *(__first + __parent) < __value)
+ {
+ *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first + __parent));
+ __holeIndex = __parent;
+ __parent = (__holeIndex - 1) / 2;
+ }
+ *(__first + __holeIndex) = _GLIBCXX_MOVE(__value);
}
+ /**
+ * @brief Push an element onto a heap.
+ * @param first Start of heap.
+ * @param last End of heap + element.
+ * @ingroup heap_algorithms
+ *
+ * This operation pushes the element at last-1 onto the valid heap over the
+ * range [first,last-1). After completion, [first,last) is a valid heap.
+ */
template<typename _RandomAccessIterator>
- inline void
+ inline void
push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
{
typedef typename iterator_traits<_RandomAccessIterator>::value_type
_DistanceType;
// concept requirements
- __glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
+ __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIterator>)
- __glibcpp_function_requires(_LessThanComparableConcept<_ValueType>)
+ __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
+ __glibcxx_requires_valid_range(__first, __last);
+ __glibcxx_requires_heap(__first, __last - 1);
- __push_heap(__first, _DistanceType((__last - __first) - 1), _DistanceType(0),
- _ValueType(*(__last - 1)));
+ _ValueType __value = _GLIBCXX_MOVE(*(__last - 1));
+ std::__push_heap(__first, _DistanceType((__last - __first) - 1),
+ _DistanceType(0), _GLIBCXX_MOVE(__value));
}
- template<typename _RandomAccessIterator, typename _Distance, typename _Tp,
- typename _Compare>
+ template<typename _RandomAccessIterator, typename _Distance, typename _Tp,
+ typename _Compare>
void
__push_heap(_RandomAccessIterator __first, _Distance __holeIndex,
_Distance __topIndex, _Tp __value, _Compare __comp)
{
_Distance __parent = (__holeIndex - 1) / 2;
- while (__holeIndex > __topIndex && __comp(*(__first + __parent), __value)) {
- *(__first + __holeIndex) = *(__first + __parent);
- __holeIndex = __parent;
- __parent = (__holeIndex - 1) / 2;
- }
- *(__first + __holeIndex) = __value;
+ while (__holeIndex > __topIndex
+ && __comp(*(__first + __parent), __value))
+ {
+ *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first + __parent));
+ __holeIndex = __parent;
+ __parent = (__holeIndex - 1) / 2;
+ }
+ *(__first + __holeIndex) = _GLIBCXX_MOVE(__value);
}
+ /**
+ * @brief Push an element onto a heap using comparison functor.
+ * @param first Start of heap.
+ * @param last End of heap + element.
+ * @param comp Comparison functor.
+ * @ingroup heap_algorithms
+ *
+ * This operation pushes the element at last-1 onto the valid heap over the
+ * range [first,last-1). After completion, [first,last) is a valid heap.
+ * Compare operations are performed using comp.
+ */
template<typename _RandomAccessIterator, typename _Compare>
- inline void
+ inline void
push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
_Compare __comp)
{
_DistanceType;
// concept requirements
- __glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
+ __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIterator>)
+ __glibcxx_requires_valid_range(__first, __last);
+ __glibcxx_requires_heap_pred(__first, __last - 1, __comp);
- __push_heap(__first, _DistanceType((__last - __first) - 1), _DistanceType(0),
- _ValueType(*(__last - 1)), __comp);
+ _ValueType __value = _GLIBCXX_MOVE(*(__last - 1));
+ std::__push_heap(__first, _DistanceType((__last - __first) - 1),
+ _DistanceType(0), _GLIBCXX_MOVE(__value), __comp);
}
template<typename _RandomAccessIterator, typename _Distance, typename _Tp>
- void
+ void
__adjust_heap(_RandomAccessIterator __first, _Distance __holeIndex,
_Distance __len, _Tp __value)
{
- _Distance __topIndex = __holeIndex;
- _Distance __secondChild = 2 * __holeIndex + 2;
- while (__secondChild < __len) {
- if (*(__first + __secondChild) < *(__first + (__secondChild - 1)))
- __secondChild--;
- *(__first + __holeIndex) = *(__first + __secondChild);
- __holeIndex = __secondChild;
- __secondChild = 2 * (__secondChild + 1);
- }
- if (__secondChild == __len) {
- *(__first + __holeIndex) = *(__first + (__secondChild - 1));
- __holeIndex = __secondChild - 1;
- }
- __push_heap(__first, __holeIndex, __topIndex, __value);
+ const _Distance __topIndex = __holeIndex;
+ _Distance __secondChild = __holeIndex;
+ while (__secondChild < (__len - 1) / 2)
+ {
+ __secondChild = 2 * (__secondChild + 1);
+ if (*(__first + __secondChild) < *(__first + (__secondChild - 1)))
+ __secondChild--;
+ *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first + __secondChild));
+ __holeIndex = __secondChild;
+ }
+ if ((__len & 1) == 0 && __secondChild == (__len - 2) / 2)
+ {
+ __secondChild = 2 * (__secondChild + 1);
+ *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first
+ + (__secondChild - 1)));
+ __holeIndex = __secondChild - 1;
+ }
+ std::__push_heap(__first, __holeIndex, __topIndex,
+ _GLIBCXX_MOVE(__value));
}
- template<typename _RandomAccessIterator, typename _Tp>
- inline void
+ template<typename _RandomAccessIterator>
+ inline void
__pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
- _RandomAccessIterator __result, _Tp __value)
+ _RandomAccessIterator __result)
{
- typedef typename iterator_traits<_RandomAccessIterator>::difference_type _Distance;
- *__result = *__first;
- __adjust_heap(__first, _Distance(0), _Distance(__last - __first), __value);
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type
+ _ValueType;
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type
+ _DistanceType;
+
+ _ValueType __value = _GLIBCXX_MOVE(*__result);
+ *__result = _GLIBCXX_MOVE(*__first);
+ std::__adjust_heap(__first, _DistanceType(0),
+ _DistanceType(__last - __first),
+ _GLIBCXX_MOVE(__value));
}
+ /**
+ * @brief Pop an element off a heap.
+ * @param first Start of heap.
+ * @param last End of heap.
+ * @ingroup heap_algorithms
+ *
+ * This operation pops the top of the heap. The elements first and last-1
+ * are swapped and [first,last-1) is made into a heap.
+ */
template<typename _RandomAccessIterator>
inline void
pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
{
- typedef typename iterator_traits<_RandomAccessIterator>::value_type _ValueType;
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type
+ _ValueType;
// concept requirements
- __glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
+ __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIterator>)
- __glibcpp_function_requires(_LessThanComparableConcept<_ValueType>)
+ __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
+ __glibcxx_requires_valid_range(__first, __last);
+ __glibcxx_requires_heap(__first, __last);
- __pop_heap(__first, __last - 1, __last - 1, _ValueType(*(__last - 1)));
+ --__last;
+ std::__pop_heap(__first, __last, __last);
}
template<typename _RandomAccessIterator, typename _Distance,
__adjust_heap(_RandomAccessIterator __first, _Distance __holeIndex,
_Distance __len, _Tp __value, _Compare __comp)
{
- _Distance __topIndex = __holeIndex;
- _Distance __secondChild = 2 * __holeIndex + 2;
- while (__secondChild < __len) {
- if (__comp(*(__first + __secondChild), *(__first + (__secondChild - 1))))
- __secondChild--;
- *(__first + __holeIndex) = *(__first + __secondChild);
- __holeIndex = __secondChild;
- __secondChild = 2 * (__secondChild + 1);
- }
- if (__secondChild == __len) {
- *(__first + __holeIndex) = *(__first + (__secondChild - 1));
- __holeIndex = __secondChild - 1;
- }
- __push_heap(__first, __holeIndex, __topIndex, __value, __comp);
+ const _Distance __topIndex = __holeIndex;
+ _Distance __secondChild = __holeIndex;
+ while (__secondChild < (__len - 1) / 2)
+ {
+ __secondChild = 2 * (__secondChild + 1);
+ if (__comp(*(__first + __secondChild),
+ *(__first + (__secondChild - 1))))
+ __secondChild--;
+ *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first + __secondChild));
+ __holeIndex = __secondChild;
+ }
+ if ((__len & 1) == 0 && __secondChild == (__len - 2) / 2)
+ {
+ __secondChild = 2 * (__secondChild + 1);
+ *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first
+ + (__secondChild - 1)));
+ __holeIndex = __secondChild - 1;
+ }
+ std::__push_heap(__first, __holeIndex, __topIndex,
+ _GLIBCXX_MOVE(__value), __comp);
}
- template<typename _RandomAccessIterator, typename _Tp, typename _Compare>
- inline void
+ template<typename _RandomAccessIterator, typename _Compare>
+ inline void
__pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
- _RandomAccessIterator __result, _Tp __value, _Compare __comp)
+ _RandomAccessIterator __result, _Compare __comp)
{
- typedef typename iterator_traits<_RandomAccessIterator>::difference_type _Distance;
- *__result = *__first;
- __adjust_heap(__first, _Distance(0), _Distance(__last - __first),
- __value, __comp);
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type
+ _ValueType;
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type
+ _DistanceType;
+
+ _ValueType __value = _GLIBCXX_MOVE(*__result);
+ *__result = _GLIBCXX_MOVE(*__first);
+ std::__adjust_heap(__first, _DistanceType(0),
+ _DistanceType(__last - __first),
+ _GLIBCXX_MOVE(__value), __comp);
}
+ /**
+ * @brief Pop an element off a heap using comparison functor.
+ * @param first Start of heap.
+ * @param last End of heap.
+ * @param comp Comparison functor to use.
+ * @ingroup heap_algorithms
+ *
+ * This operation pops the top of the heap. The elements first and last-1
+ * are swapped and [first,last-1) is made into a heap. Comparisons are
+ * made using comp.
+ */
template<typename _RandomAccessIterator, typename _Compare>
- inline void
+ inline void
pop_heap(_RandomAccessIterator __first,
_RandomAccessIterator __last, _Compare __comp)
{
// concept requirements
- __glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
+ __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIterator>)
+ __glibcxx_requires_valid_range(__first, __last);
+ __glibcxx_requires_heap_pred(__first, __last, __comp);
- typedef typename iterator_traits<_RandomAccessIterator>::value_type _ValueType;
- __pop_heap(__first, __last - 1, __last - 1, _ValueType(*(__last - 1)), __comp);
+ --__last;
+ std::__pop_heap(__first, __last, __last, __comp);
}
+ /**
+ * @brief Construct a heap over a range.
+ * @param first Start of heap.
+ * @param last End of heap.
+ * @ingroup heap_algorithms
+ *
+ * This operation makes the elements in [first,last) into a heap.
+ */
template<typename _RandomAccessIterator>
- void
+ void
make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
{
typedef typename iterator_traits<_RandomAccessIterator>::value_type
_DistanceType;
// concept requirements
- __glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
+ __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIterator>)
- __glibcpp_function_requires(_LessThanComparableConcept<_ValueType>)
-
- if (__last - __first < 2) return;
- _DistanceType __len = __last - __first;
- _DistanceType __parent = (__len - 2)/2;
-
- while (true) {
- __adjust_heap(__first, __parent, __len, _ValueType(*(__first + __parent)));
- if (__parent == 0) return;
- __parent--;
- }
+ __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
+ __glibcxx_requires_valid_range(__first, __last);
+
+ if (__last - __first < 2)
+ return;
+
+ const _DistanceType __len = __last - __first;
+ _DistanceType __parent = (__len - 2) / 2;
+ while (true)
+ {
+ _ValueType __value = _GLIBCXX_MOVE(*(__first + __parent));
+ std::__adjust_heap(__first, __parent, __len, _GLIBCXX_MOVE(__value));
+ if (__parent == 0)
+ return;
+ __parent--;
+ }
}
+ /**
+ * @brief Construct a heap over a range using comparison functor.
+ * @param first Start of heap.
+ * @param last End of heap.
+ * @param comp Comparison functor to use.
+ * @ingroup heap_algorithms
+ *
+ * This operation makes the elements in [first,last) into a heap.
+ * Comparisons are made using comp.
+ */
template<typename _RandomAccessIterator, typename _Compare>
- inline void
+ void
make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
_Compare __comp)
{
_DistanceType;
// concept requirements
- __glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
+ __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIterator>)
-
- if (__last - __first < 2) return;
- _DistanceType __len = __last - __first;
- _DistanceType __parent = (__len - 2)/2;
-
- while (true) {
- __adjust_heap(__first, __parent, __len,
- _ValueType(*(__first + __parent)), __comp);
- if (__parent == 0) return;
- __parent--;
- }
+ __glibcxx_requires_valid_range(__first, __last);
+
+ if (__last - __first < 2)
+ return;
+
+ const _DistanceType __len = __last - __first;
+ _DistanceType __parent = (__len - 2) / 2;
+ while (true)
+ {
+ _ValueType __value = _GLIBCXX_MOVE(*(__first + __parent));
+ std::__adjust_heap(__first, __parent, __len, _GLIBCXX_MOVE(__value),
+ __comp);
+ if (__parent == 0)
+ return;
+ __parent--;
+ }
}
+ /**
+ * @brief Sort a heap.
+ * @param first Start of heap.
+ * @param last End of heap.
+ * @ingroup heap_algorithms
+ *
+ * This operation sorts the valid heap in the range [first,last).
+ */
template<typename _RandomAccessIterator>
void
sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
{
// concept requirements
- __glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
+ __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIterator>)
- __glibcpp_function_requires(_LessThanComparableConcept<
+ __glibcxx_function_requires(_LessThanComparableConcept<
typename iterator_traits<_RandomAccessIterator>::value_type>)
+ __glibcxx_requires_valid_range(__first, __last);
+ __glibcxx_requires_heap(__first, __last);
while (__last - __first > 1)
- pop_heap(__first, __last--);
+ {
+ --__last;
+ std::__pop_heap(__first, __last, __last);
+ }
}
+ /**
+ * @brief Sort a heap using comparison functor.
+ * @param first Start of heap.
+ * @param last End of heap.
+ * @param comp Comparison functor to use.
+ * @ingroup heap_algorithms
+ *
+ * This operation sorts the valid heap in the range [first,last).
+ * Comparisons are made using comp.
+ */
template<typename _RandomAccessIterator, typename _Compare>
- void
+ void
sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
_Compare __comp)
{
// concept requirements
- __glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
+ __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIterator>)
+ __glibcxx_requires_valid_range(__first, __last);
+ __glibcxx_requires_heap_pred(__first, __last, __comp);
while (__last - __first > 1)
- pop_heap(__first, __last--, __comp);
+ {
+ --__last;
+ std::__pop_heap(__first, __last, __last, __comp);
+ }
+ }
+
+#ifdef __GXX_EXPERIMENTAL_CXX0X__
+ /**
+ * @brief Search the end of a heap.
+ * @param first Start of range.
+ * @param last End of range.
+ * @return An iterator pointing to the first element not in the heap.
+ * @ingroup heap_algorithms
+ *
+ * This operation returns the last iterator i in [first, last) for which
+ * the range [first, i) is a heap.
+ */
+ template<typename _RandomAccessIterator>
+ inline _RandomAccessIterator
+ is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last)
+ {
+ // concept requirements
+ __glibcxx_function_requires(_RandomAccessIteratorConcept<
+ _RandomAccessIterator>)
+ __glibcxx_function_requires(_LessThanComparableConcept<
+ typename iterator_traits<_RandomAccessIterator>::value_type>)
+ __glibcxx_requires_valid_range(__first, __last);
+
+ return __first + std::__is_heap_until(__first, std::distance(__first,
+ __last));
}
-} // namespace std
+ /**
+ * @brief Search the end of a heap using comparison functor.
+ * @param first Start of range.
+ * @param last End of range.
+ * @param comp Comparison functor to use.
+ * @return An iterator pointing to the first element not in the heap.
+ * @ingroup heap_algorithms
+ *
+ * This operation returns the last iterator i in [first, last) for which
+ * the range [first, i) is a heap. Comparisons are made using comp.
+ */
+ template<typename _RandomAccessIterator, typename _Compare>
+ inline _RandomAccessIterator
+ is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last,
+ _Compare __comp)
+ {
+ // concept requirements
+ __glibcxx_function_requires(_RandomAccessIteratorConcept<
+ _RandomAccessIterator>)
+ __glibcxx_requires_valid_range(__first, __last);
+
+ return __first + std::__is_heap_until(__first, std::distance(__first,
+ __last),
+ __comp);
+ }
+
+ /**
+ * @brief Determines whether a range is a heap.
+ * @param first Start of range.
+ * @param last End of range.
+ * @return True if range is a heap, false otherwise.
+ * @ingroup heap_algorithms
+ */
+ template<typename _RandomAccessIterator>
+ inline bool
+ is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
+ { return std::is_heap_until(__first, __last) == __last; }
+
+ /**
+ * @brief Determines whether a range is a heap using comparison functor.
+ * @param first Start of range.
+ * @param last End of range.
+ * @param comp Comparison functor to use.
+ * @return True if range is a heap, false otherwise.
+ * @ingroup heap_algorithms
+ */
+ template<typename _RandomAccessIterator, typename _Compare>
+ inline bool
+ is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
+ _Compare __comp)
+ { return std::is_heap_until(__first, __last, __comp) == __last; }
+#endif
-#endif /* _CPP_BITS_STL_HEAP_H */
+_GLIBCXX_END_NAMESPACE
-// Local Variables:
-// mode:C++
-// End:
+#endif /* _STL_HEAP_H */