// CS 1538 Fall 2009
// Simple demonstration of Monte Carlo simulation to test the "Let's Make
// a Deal" problem

import java.util.*;
public class MontyMonte
{
	public static void main(String [] args)
	{
		int iter = Integer.parseInt(args[0]);
		Random r = new Random();
		int winsA = 0;
		int winsB = 0;
		for (int i = 0; i < iter; i++)
		{
			// Without loss of generality, player will always initially
			// guess curtain 0
			int guessA = 0, guessB = 0;
			int winner = r.nextInt(3); // Pick random winning curtain
			int loser;
			if (winner == 1)	// Pick "wrong" curtain to reveal
				loser = 2;
			else if (winner == 2)
				loser = 1;
			else
				loser = r.nextInt(2) + 1;  // Winner is 0, so pick
							// "loser" at random between 1 and 2

			if (loser == 1)		// Player switches guess after
				guessB = 2;		// reveal
			else
				guessB = 1;
			if (winner == guessA)
				winsA++;
			if (winner == guessB)
				winsB++;
		}
		double pctA = (double)winsA / iter;
		double pctB = (double)winsB / iter;
		System.out.println("Non-switch pct. = " + pctA);
		System.out.println("Switch pct. = " + pctB);
	}
}