The C++ Standard Library consists of the header, <algorithm> which defines a collection of functions (principally designed to deal with a range of elements). pop_heap() is a method in the STL that is used to delete an element from a heap. The size of the heap effectively decreases by one.
Syntax:
pop_heap( iterator_begin, iterator_end, comparator ); //comparator is optional
Parameters: The pop_heap() method accepts 3 parameters
- iterator_begin: Iterator to the initial position of heap
- iterator_end: Iterator to the final position of heap ( Note: the range is [iterator_begin,iterator_end) )
- comparator: Binary function that accepts two elements in the range as arguments, and returns a value convertible to bool.
Return value: none
Example of pop_heap() method
#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
int main()
{
vector<int> v;
v.push_back(4);
v.push_back(3);
v.push_back(8);
v.push_back(-5);
v.push_back(7);
make_heap(v.begin(), v.end());
cout<<"Initial heap: "<<v.front()<<endl; //max val
pop_heap(v.begin(), v.end());
cout<<"New heap: "<<v.front()<<endl; //max val
}
Output:
Initial heap: 8 New heap: 7
