priority_queue::pop() method

A priority queue is a dynamically resizing container adopter in the C++ Standard Library. Elements in a priority queue are arranged in non-decreasing order such that the first element is always the greatest element in the queue. The priority_queue::pop() is a method available in the STL which removes the element on top (largest element) of the queue, effectively reducing its size by one.

Syntax:

priorityq_name.pop();

Parameter: The priority_queue::pop() does not accept any parameter
Return value: none

Example of priority_queue::pop() method

#include <iostream>>
#include <queue>

using namespace std;

void print_q(priority_queue <int> q) //helper function to print the contents of a priority queue
{
    priority_queue <int> temp = q;
    while (!temp.empty())
    {
        cout<<temp.top()<<"\t";
        temp.pop();
    }
    cout<<endl;
}


int main ()
{
    priority_queue<int> q;

    q.push(10);
    q.push(20);
    q.push(40);
    q.push(30);

    cout<<"Before pop: \n";
    print_q(q);
    q.pop();
    cout<<"After pop: \n";
    print_q(q);

    return 0;
}

Output:

Before pop:
40  30  20  10
After pop:
30  20  10