all priority_queue functions

// Priority Queues are like queues, but the
// elements inside the data structure are
// ordered by some predicate. 
#include <iostream>
#include <queue>
#include <vector>
#include <string>
using namespace std;

int main ()
{
    priority_queue<int, vector<int>, less<int> > ipq;
    ipq.push(100);
    ipq.push(200);
    ipq.push(300);

    cout << "size of priority_queue ipq = "
         << ipq.size() << endl;

    cout << "ipq <int,vector<int>, less<int> > = ";
    while ( !ipq.empty() )
    {
        cout << ipq.top() << " ";
        ipq.pop();
    }
    cout << endl << endl;
	
    cout << "priority_queue<string,vector<string> > spq;"
         << endl;

    priority_queue<string,vector<string> > spq;
    for ( int i=1; i<10; i++ )
        spq.push(string(i,'*'));

    while ( !spq.empty() )
    {
        cout << spq.top() << endl;
        spq.pop();
    }

    return 0;
}
OUTPUT:
// size of priority_queue ipq = 3
// ipq <sring,vector<string> > = 300 200 100
//
// priority_queue<string,vector<string> > spq;
// *********
// ********
// *******
// ******
// *****
// ****
// ***
// **
// *