How to implement max heap with pair using priority queue in java?

Question

I am trying to implement Max heap with key value pair in java. As we know in C++ we can do that in this way..

    priority_queue<pair<int, int> > pq;
    pq.push(make_pair(10, 200));
    pq.push(make_pair(20, 100));
    pq.push(make_pair(15, 400));

But I am unable to do this in java, please help me to do so.

Answer 1

In Java you can use a HashMap for that:

import javafx.util.Pair;
import java.util.PriorityQueue;

public class YourClass{

    public static void main (String[] args){

        int n = 3;

PriorityQueue<Pair<Integer,Integer> > pq = new PriorityQueue<Pair<Integer,Integer>>(n, Comparator.comparing(Pair::getKey));

  /*Adding elements to HashMap*/
  pq.add(new Pair <> (10, 200));
  pq.add(new Pair <> (20, 100));
  pq.add(new Pair <> (15, 400));

 System.out.println(l.poll().getValue()); 
    }
}