The C++ Standard Library consists of the header, <algorithm>
which defines a collection of functions (principally designed to deal with a range of elements). is_heap()
is a method in the STL that tests if a certain range of a container is a heap.
Syntax:
is_heap( iterator_begin, iterator_end, comparator ); //comparator is optional
Parameters: The is_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: true if range is a heap, false otherwise
Example of is_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); if(!is_heap(v.begin(), v.end())) { cout<<"It's not a heap"<<endl; make_heap(v.begin(), v.end()); } if(is_heap(v.begin(), v.end())) { cout<<"make_heap ordered vector into heap!"<<endl; } }
Output:
It's not a heap make_heap ordered vector into heap!