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			541 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			541 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			C++
		
	
	
	
| // Heap implementation -*- C++ -*-
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| 
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| // Copyright (C) 2001-2016 Free Software Foundation, Inc.
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| //
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| // This file is part of the GNU ISO C++ Library.  This library is free
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| // software; you can redistribute it and/or modify it under the
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| // terms of the GNU General Public License as published by the
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| // Free Software Foundation; either version 3, or (at your option)
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| // any later version.
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| 
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| // This library is distributed in the hope that it will be useful,
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| // but WITHOUT ANY WARRANTY; without even the implied warranty of
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| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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| // GNU General Public License for more details.
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| 
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| // Under Section 7 of GPL version 3, you are granted additional
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| // permissions described in the GCC Runtime Library Exception, version
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| // 3.1, as published by the Free Software Foundation.
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| 
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| // You should have received a copy of the GNU General Public License and
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| // a copy of the GCC Runtime Library Exception along with this program;
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| // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
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| // <http://www.gnu.org/licenses/>.
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| 
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| /*
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|  *
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|  * Copyright (c) 1994
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|  * Hewlett-Packard Company
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|  *
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|  * Permission to use, copy, modify, distribute and sell this software
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|  * and its documentation for any purpose is hereby granted without fee,
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|  * provided that the above copyright notice appear in all copies and
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|  * that both that copyright notice and this permission notice appear
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|  * in supporting documentation.  Hewlett-Packard Company makes no
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|  * representations about the suitability of this software for any
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|  * purpose.  It is provided "as is" without express or implied warranty.
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|  *
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|  * Copyright (c) 1997
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|  * Silicon Graphics Computer Systems, Inc.
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|  *
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|  * Permission to use, copy, modify, distribute and sell this software
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|  * and its documentation for any purpose is hereby granted without fee,
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|  * provided that the above copyright notice appear in all copies and
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|  * that both that copyright notice and this permission notice appear
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|  * in supporting documentation.  Silicon Graphics makes no
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|  * representations about the suitability of this software for any
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|  * purpose.  It is provided "as is" without express or implied warranty.
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|  */
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| 
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| /** @file bits/stl_heap.h
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|  *  This is an internal header file, included by other library headers.
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|  *  Do not attempt to use it directly. @headername{queue}
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|  */
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| 
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| #ifndef _STL_HEAP_H
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| #define _STL_HEAP_H 1
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| 
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| #include <debug/debug.h>
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| #include <bits/move.h>
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| #include <bits/predefined_ops.h>
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| 
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| namespace std _GLIBCXX_VISIBILITY(default)
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| {
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| _GLIBCXX_BEGIN_NAMESPACE_VERSION
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| 
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|   /**
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|    * @defgroup heap_algorithms Heap
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|    * @ingroup sorting_algorithms
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|    */
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| 
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|   template<typename _RandomAccessIterator, typename _Distance,
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| 	   typename _Compare>
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|     _Distance
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|     __is_heap_until(_RandomAccessIterator __first, _Distance __n,
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| 		    _Compare __comp)
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|     {
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|       _Distance __parent = 0;
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|       for (_Distance __child = 1; __child < __n; ++__child)
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| 	{
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| 	  if (__comp(__first + __parent, __first + __child))
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| 	    return __child;
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| 	  if ((__child & 1) == 0)
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| 	    ++__parent;
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| 	}
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|       return __n;
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|     }
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| 
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|   // __is_heap, a predicate testing whether or not a range is a heap.
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|   // This function is an extension, not part of the C++ standard.
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|   template<typename _RandomAccessIterator, typename _Distance>
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|     inline bool
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|     __is_heap(_RandomAccessIterator __first, _Distance __n)
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|     {
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|       return std::__is_heap_until(__first, __n,
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| 			__gnu_cxx::__ops::__iter_less_iter()) == __n;
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|     }
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| 
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|   template<typename _RandomAccessIterator, typename _Compare,
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| 	   typename _Distance>
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|     inline bool
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|     __is_heap(_RandomAccessIterator __first, _Compare __comp, _Distance __n)
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|     {
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|       return std::__is_heap_until(__first, __n,
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| 	__gnu_cxx::__ops::__iter_comp_iter(__comp)) == __n;
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|     }
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| 
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|   template<typename _RandomAccessIterator>
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|     inline bool
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|     __is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
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|     { return std::__is_heap(__first, std::distance(__first, __last)); }
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| 
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|   template<typename _RandomAccessIterator, typename _Compare>
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|     inline bool
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|     __is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
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| 	      _Compare __comp)
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|     { return std::__is_heap(__first, __comp, std::distance(__first, __last)); }
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| 
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|   // Heap-manipulation functions: push_heap, pop_heap, make_heap, sort_heap,
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|   // + is_heap and is_heap_until in C++0x.
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| 
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|   template<typename _RandomAccessIterator, typename _Distance, typename _Tp,
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| 	   typename _Compare>
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|     void
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|     __push_heap(_RandomAccessIterator __first,
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| 		_Distance __holeIndex, _Distance __topIndex, _Tp __value,
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| 		_Compare __comp)
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|     {
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|       _Distance __parent = (__holeIndex - 1) / 2;
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|       while (__holeIndex > __topIndex && __comp(__first + __parent, __value))
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| 	{
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| 	  *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first + __parent));
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| 	  __holeIndex = __parent;
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| 	  __parent = (__holeIndex - 1) / 2;
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| 	}
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|       *(__first + __holeIndex) = _GLIBCXX_MOVE(__value);
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|     }
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| 
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|   /**
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|    *  @brief  Push an element onto a heap.
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|    *  @param  __first  Start of heap.
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|    *  @param  __last   End of heap + element.
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|    *  @ingroup heap_algorithms
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|    *
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|    *  This operation pushes the element at last-1 onto the valid heap
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|    *  over the range [__first,__last-1).  After completion,
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|    *  [__first,__last) is a valid heap.
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|   */
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|   template<typename _RandomAccessIterator>
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|     inline void
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|     push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
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|     {
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|       typedef typename iterator_traits<_RandomAccessIterator>::value_type
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| 	  _ValueType;
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|       typedef typename iterator_traits<_RandomAccessIterator>::difference_type
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| 	  _DistanceType;
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| 
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|       // concept requirements
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|       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
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| 	    _RandomAccessIterator>)
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|       __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
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|       __glibcxx_requires_valid_range(__first, __last);
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|       __glibcxx_requires_irreflexive(__first, __last);
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|       __glibcxx_requires_heap(__first, __last - 1);
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| 
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|       _ValueType __value = _GLIBCXX_MOVE(*(__last - 1));
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|       std::__push_heap(__first, _DistanceType((__last - __first) - 1),
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| 		       _DistanceType(0), _GLIBCXX_MOVE(__value),
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| 		       __gnu_cxx::__ops::__iter_less_val());
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|     }
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| 
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|   /**
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|    *  @brief  Push an element onto a heap using comparison functor.
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|    *  @param  __first  Start of heap.
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|    *  @param  __last   End of heap + element.
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|    *  @param  __comp   Comparison functor.
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|    *  @ingroup heap_algorithms
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|    *
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|    *  This operation pushes the element at __last-1 onto the valid
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|    *  heap over the range [__first,__last-1).  After completion,
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|    *  [__first,__last) is a valid heap.  Compare operations are
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|    *  performed using comp.
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|   */
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|   template<typename _RandomAccessIterator, typename _Compare>
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|     inline void
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|     push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
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| 	      _Compare __comp)
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|     {
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|       typedef typename iterator_traits<_RandomAccessIterator>::value_type
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| 	  _ValueType;
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|       typedef typename iterator_traits<_RandomAccessIterator>::difference_type
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| 	  _DistanceType;
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| 
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|       // concept requirements
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|       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
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| 	    _RandomAccessIterator>)
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|       __glibcxx_requires_valid_range(__first, __last);
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|       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
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|       __glibcxx_requires_heap_pred(__first, __last - 1, __comp);
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| 
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|       _ValueType __value = _GLIBCXX_MOVE(*(__last - 1));
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|       std::__push_heap(__first, _DistanceType((__last - __first) - 1),
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| 		       _DistanceType(0), _GLIBCXX_MOVE(__value),
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| 		       __gnu_cxx::__ops::__iter_comp_val(__comp));
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|     }
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| 
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|   template<typename _RandomAccessIterator, typename _Distance,
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| 	   typename _Tp, typename _Compare>
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|     void
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|     __adjust_heap(_RandomAccessIterator __first, _Distance __holeIndex,
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| 		  _Distance __len, _Tp __value, _Compare __comp)
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|     {
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|       const _Distance __topIndex = __holeIndex;
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|       _Distance __secondChild = __holeIndex;
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|       while (__secondChild < (__len - 1) / 2)
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| 	{
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| 	  __secondChild = 2 * (__secondChild + 1);
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| 	  if (__comp(__first + __secondChild,
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| 		     __first + (__secondChild - 1)))
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| 	    __secondChild--;
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| 	  *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first + __secondChild));
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| 	  __holeIndex = __secondChild;
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| 	}
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|       if ((__len & 1) == 0 && __secondChild == (__len - 2) / 2)
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| 	{
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| 	  __secondChild = 2 * (__secondChild + 1);
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| 	  *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first
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| 						     + (__secondChild - 1)));
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| 	  __holeIndex = __secondChild - 1;
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| 	}
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|       std::__push_heap(__first, __holeIndex, __topIndex, 
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| 		       _GLIBCXX_MOVE(__value),
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| 		       __gnu_cxx::__ops::__iter_comp_val(__comp));
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|     }
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| 
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|   template<typename _RandomAccessIterator, typename _Compare>
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|     inline void
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|     __pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
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| 	       _RandomAccessIterator __result, _Compare __comp)
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|     {
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|       typedef typename iterator_traits<_RandomAccessIterator>::value_type
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| 	_ValueType;
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|       typedef typename iterator_traits<_RandomAccessIterator>::difference_type
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| 	_DistanceType;
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| 
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|       _ValueType __value = _GLIBCXX_MOVE(*__result);
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|       *__result = _GLIBCXX_MOVE(*__first);
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|       std::__adjust_heap(__first, _DistanceType(0),
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| 			 _DistanceType(__last - __first),
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| 			 _GLIBCXX_MOVE(__value), __comp);
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|     }
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| 
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|   /**
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|    *  @brief  Pop an element off a heap.
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|    *  @param  __first  Start of heap.
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|    *  @param  __last   End of heap.
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|    *  @pre    [__first, __last) is a valid, non-empty range.
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|    *  @ingroup heap_algorithms
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|    *
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|    *  This operation pops the top of the heap.  The elements __first
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|    *  and __last-1 are swapped and [__first,__last-1) is made into a
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|    *  heap.
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|   */
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|   template<typename _RandomAccessIterator>
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|     inline void
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|     pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
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|     {
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|       // concept requirements
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|       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
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| 	    _RandomAccessIterator>)
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|       __glibcxx_function_requires(_LessThanComparableConcept<
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| 	typename iterator_traits<_RandomAccessIterator>::value_type>)
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|       __glibcxx_requires_non_empty_range(__first, __last);
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|       __glibcxx_requires_valid_range(__first, __last);
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|       __glibcxx_requires_irreflexive(__first, __last);
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|       __glibcxx_requires_heap(__first, __last);
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| 
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|       if (__last - __first > 1)
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| 	{
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| 	  --__last;
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| 	  std::__pop_heap(__first, __last, __last,
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| 			  __gnu_cxx::__ops::__iter_less_iter());
 | |
| 	}
 | |
|     }
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| 
 | |
|   /**
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|    *  @brief  Pop an element off a heap using comparison functor.
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|    *  @param  __first  Start of heap.
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|    *  @param  __last   End of heap.
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|    *  @param  __comp   Comparison functor to use.
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|    *  @ingroup heap_algorithms
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|    *
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|    *  This operation pops the top of the heap.  The elements __first
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|    *  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
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|     pop_heap(_RandomAccessIterator __first,
 | |
| 	     _RandomAccessIterator __last, _Compare __comp)
 | |
|     {
 | |
|       // concept requirements
 | |
|       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
 | |
| 	    _RandomAccessIterator>)
 | |
|       __glibcxx_requires_valid_range(__first, __last);
 | |
|       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 | |
|       __glibcxx_requires_non_empty_range(__first, __last);
 | |
|       __glibcxx_requires_heap_pred(__first, __last, __comp);
 | |
| 
 | |
|       if (__last - __first > 1)
 | |
| 	{
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| 	  --__last;
 | |
| 	  std::__pop_heap(__first, __last, __last,
 | |
| 			  __gnu_cxx::__ops::__iter_comp_iter(__comp));
 | |
| 	}
 | |
|     }
 | |
| 
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|   template<typename _RandomAccessIterator, typename _Compare>
 | |
|     void
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|     __make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
 | |
| 		_Compare __comp)
 | |
|     {
 | |
|       typedef typename iterator_traits<_RandomAccessIterator>::value_type
 | |
| 	  _ValueType;
 | |
|       typedef typename iterator_traits<_RandomAccessIterator>::difference_type
 | |
| 	  _DistanceType;
 | |
| 
 | |
|       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  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>
 | |
|     inline void
 | |
|     make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
 | |
|     {
 | |
|       // concept requirements
 | |
|       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
 | |
| 	    _RandomAccessIterator>)
 | |
|       __glibcxx_function_requires(_LessThanComparableConcept<
 | |
| 	    typename iterator_traits<_RandomAccessIterator>::value_type>)
 | |
|       __glibcxx_requires_valid_range(__first, __last);
 | |
|       __glibcxx_requires_irreflexive(__first, __last);
 | |
| 
 | |
|       std::__make_heap(__first, __last,
 | |
| 		       __gnu_cxx::__ops::__iter_less_iter());
 | |
|     }
 | |
| 
 | |
|   /**
 | |
|    *  @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
 | |
|     make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
 | |
| 	      _Compare __comp)
 | |
|     {
 | |
|       // concept requirements
 | |
|       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
 | |
| 	    _RandomAccessIterator>)
 | |
|       __glibcxx_requires_valid_range(__first, __last);
 | |
|       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 | |
| 
 | |
|       std::__make_heap(__first, __last,
 | |
| 		       __gnu_cxx::__ops::__iter_comp_iter(__comp));
 | |
|     }
 | |
| 
 | |
|   template<typename _RandomAccessIterator, typename _Compare>
 | |
|     void
 | |
|     __sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
 | |
| 		_Compare __comp)
 | |
|     {
 | |
|       while (__last - __first > 1)
 | |
| 	{
 | |
| 	  --__last;
 | |
| 	  std::__pop_heap(__first, __last, __last, __comp);
 | |
| 	}
 | |
|     }
 | |
| 
 | |
|   /**
 | |
|    *  @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>
 | |
|     inline void
 | |
|     sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
 | |
|     {
 | |
|       // concept requirements
 | |
|       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
 | |
| 	    _RandomAccessIterator>)
 | |
|       __glibcxx_function_requires(_LessThanComparableConcept<
 | |
| 	    typename iterator_traits<_RandomAccessIterator>::value_type>)
 | |
|       __glibcxx_requires_valid_range(__first, __last);
 | |
|       __glibcxx_requires_irreflexive(__first, __last);
 | |
|       __glibcxx_requires_heap(__first, __last);
 | |
| 
 | |
|       std::__sort_heap(__first, __last,
 | |
| 		       __gnu_cxx::__ops::__iter_less_iter());
 | |
|     }
 | |
| 
 | |
|   /**
 | |
|    *  @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>
 | |
|     inline void
 | |
|     sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
 | |
| 	      _Compare __comp)
 | |
|     {
 | |
|       // concept requirements
 | |
|       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
 | |
| 	    _RandomAccessIterator>)
 | |
|       __glibcxx_requires_valid_range(__first, __last);
 | |
|       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 | |
|       __glibcxx_requires_heap_pred(__first, __last, __comp);
 | |
| 
 | |
|       std::__sort_heap(__first, __last,
 | |
| 		       __gnu_cxx::__ops::__iter_comp_iter(__comp));
 | |
|     }
 | |
| 
 | |
| #if __cplusplus >= 201103L
 | |
|   /**
 | |
|    *  @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);
 | |
|       __glibcxx_requires_irreflexive(__first, __last);
 | |
| 
 | |
|       return __first + 
 | |
| 	std::__is_heap_until(__first, std::distance(__first, __last),
 | |
| 			     __gnu_cxx::__ops::__iter_less_iter());
 | |
|     }
 | |
| 
 | |
|   /**
 | |
|    *  @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);
 | |
|       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 | |
| 
 | |
|       return __first
 | |
| 	+ std::__is_heap_until(__first, std::distance(__first, __last),
 | |
| 			       __gnu_cxx::__ops::__iter_comp_iter(__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
 | |
| 
 | |
| _GLIBCXX_END_NAMESPACE_VERSION
 | |
| } // namespace
 | |
| 
 | |
| #endif /* _STL_HEAP_H */
 |