Monty Hall Problem Simulation

MontyHallSimulation.java

import java.util.Random;

public class MontyHallSimulation {

    public static void main(String[] args) {
    	new MontyHallSimulation().start();
    }

	private Random rand = new Random(4);
    
	private void start() {
    	int winstrat1 = 0;
    	int winstrat2 = 0;

    	for (int i = 0; i < 1e6; ++i) {
    		if (strat1()) {
    			++winstrat1;
			}
			if (strat2()) {
    			++winstrat2;
			}
		}

		System.out.println(winstrat1);
		System.out.println(winstrat2);
	}

	/**
	 * Don't change choice when offered, stick with initial choice.
	 */
	private boolean strat1() {
		return rand.nextInt(3) == rand.nextInt(3);
	}

	/**
	 * Switch after offered a choice and one loser revealed.
	 */
	private boolean strat2() {
		// prepare starting condition
		int win = rand.nextInt(3);
		int choice = rand.nextInt(3);
		int lose1;
		int lose2;

		// figure out loses
		switch (win) {
			case 0:
				lose1 = 1;
				lose2 = 2;
				break;
			case 1:
				lose1 = 0;
				lose2 = 2;
				break;
			case 2:
				lose1 = 0;
				lose2 = 1;
				break;
			default:
				throw new RuntimeException("no");
		}

		// whenever the loser was chosen in the first stage
		// the swap in the second stage makes it a winner
		return lose1 == choice || choice == lose2;
	}

}