// Max Heap:

// Java program to demonstrate working of PriorityQueue in Java
import java.util.*;

class Test{
    public static void main(String args[])
    {
        // Creating empty priority queue
        PriorityQueue<Integer> pq 
        = new PriorityQueue<Integer>(
            Collections.reverseOrder());

        // Adding items to the pQueue using add()
        pq.add(10);
        pq.add(20);
        pq.add(15);
        
        // Above PriorityQueue is stored as following
        //       20
        //      /  \
        //    10    15

        // Printing the top element of PriorityQueue
        System.out.println(pq.peek());

        // Printing the top element and removing it
        // from the PriorityQueue container
        System.out.println(pq.poll());

        // Post poll() PriorityQueue looks like
        //       15
        //      /  
        //    10   

        // Printing the top element again
        System.out.println(pq.peek());
    }
}

// OUTPUT : 
10
10
15










// Min Heap(default)

// Java program to demonstrate working of PriorityQueue in Java
import java.util.*;

class Test{
    public static void main(String args[])
    {
        // Creating empty priority queue
        PriorityQueue<Integer> pq = new PriorityQueue<Integer>();

        // Adding items to the pQueue using add()
        pq.add(10);
        pq.add(20);
        pq.add(15);
        
       
        // Printing the top element of PriorityQueue
        System.out.println(pq.peek());

        // Printing the top element and removing it
        // from the PriorityQueue container
        System.out.println(pq.poll());


        // Printing the top element again
        System.out.println(pq.peek());
    }
}

// OUTPUT : 
20
20
15