push_heap
添加范围内结束时将包括在范围的现有堆的元素的元素。
template<class RandomAccessIterator>
void push_heap(
RandomAccessIterator _First,
RandomAccessIterator _Last
);
template<class RandomAccessIterator, class BinaryPredicate>
void push_heap(
RandomAccessIterator _First,
RandomAccessIterator _Last,
BinaryPredicate _Comp
);
参数
_First
解决一个随机访问迭代器第一个元素的位置在堆。_Last
解决一个随机访问迭代器通过最终元素的位置一在要转换的范围转换为堆。_Comp
定义含义的用户定义的谓词函数对象哪个元素比另一个小于。二进制谓词采用两个参数并返回 true ,在满足和 false,在未满足。
备注
必须先驱动器元素返回到现有堆的末尾算法然后使用将此元素添加到现有堆。
堆具有两个属性:
第一个元素始终最大。
元素在对数时可以添加或移除。
堆是一个理想方式实现优先级队列,并用于标准模板库(stl)容器适配器 priority_queue选件类的实现。
引用的范围必须是有效的;所有指针必须dereferenceable,并在该序列中最后位置以访问按增量。
除新添加的元素的范围在末尾必须是堆。
复杂是对数的要求,至多记录(_Last – _First)进行比较。
示例
// alg_push_heap.cpp
// compile with: /EHsc
#include <vector>
#include <algorithm>
#include <functional>
#include <iostream>
int main( ) {
using namespace std;
vector <int> v1, v2;
vector <int>::iterator Iter1, Iter2;
int i;
for ( i = 1 ; i <= 9 ; i++ )
v1.push_back( i );
random_shuffle( v1.begin( ), v1.end( ) );
cout << "Vector v1 is ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")." << endl;
// Make v1 a heap with default less than ordering
make_heap ( v1.begin( ), v1.end( ) );
cout << "The heaped version of vector v1 is ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")." << endl;
// Add an element to the heap
v1.push_back( 10 );
cout << "The heap v1 with 10 pushed back is ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")." << endl;
push_heap( v1.begin( ), v1.end( ) );
cout << "The reheaped v1 with 10 added is ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")." << endl << endl;
// Make v1 a heap with greater than ordering
make_heap ( v1.begin( ), v1.end( ), greater<int>( ) );
cout << "The greater-than heaped version of v1 is\n ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")." << endl;
v1.push_back(0);
cout << "The greater-than heap v1 with 11 pushed back is\n ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")." << endl;
push_heap( v1.begin( ), v1.end( ), greater<int>( ) );
cout << "The greater than reheaped v1 with 11 added is\n ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")." << endl;
}
示例输出
Vector v1 is ( 9 2 7 3 1 6 8 4 5 ).
The heaped version of vector v1 is ( 9 5 8 4 1 6 7 2 3 ).
The heap v1 with 10 pushed back is ( 9 5 8 4 1 6 7 2 3 10 ).
The reheaped v1 with 10 added is ( 10 9 8 4 5 6 7 2 3 1 ).
The greater-than heaped version of v1 is
( 1 2 6 3 5 8 7 4 10 9 ).
The greater-than heap v1 with 11 pushed back is
( 1 2 6 3 5 8 7 4 10 9 0 ).
The greater than reheaped v1 with 11 added is
( 0 1 6 3 2 8 7 4 10 9 5 ).
要求
标头: <algorithm>
命名空间: std