A dice game

DiceGame.java

import java.util.PriorityQueue;

public class DiceGame {
	
	/*
	 * We are playing a dice game. 
	 * Player A plays with 2 dice.
	 * Player B plays with 3 dice.
	 * Player A adds up the eyes of both rolls.
	 * Player B chooses the two highest and adds up these.
	 * If both eyes are equal player A wins.
	 * What are the probabilities for both players to win?
	 */
	
	public static void main(String[] args) {
		int an = 0;
		int bn = 0;
		int n = 1000000;
		for (int i = 0; i < n; i++) {
			int a = nkrand(2, 2);
			int b = nkrand(2, 3);
			if (a >= b) an++; // if equals a wins
			if (a < b) bn++;
		}
		System.out.println("A: " + (double) an / n);
		System.out.println("B: " + (double) bn / n);
	}
	
	
	/**
	 * A function that returns the eyes total of the highest n rolls of overall k rolls
	 * @param n add up the highest n numbers
	 * @param k from k rolls
	 */
	private static int nkrand(int n, int k) {
		
		if (n > k) throw new Error();
		
		PriorityQueue<Integer> pq = new PriorityQueue<>((x, y) -> y - x);
		
		for (int i = 0; i < k; i++) {
			pq.add(rand());
		}
		
		int sum = 0;
		for (int i = 0; i < n; i++) {
			sum += pq.poll();
		}
		return sum;
	}
	
	private static int rand() {
		return ((int) (Math.random()*6)) + 1;
	}
}