// $Id: ackermann.java,v 1.2 2005-05-13 16:24:17 igouy-guest Exp $
// http://www.bagley.org/~doug/shootout/ 

public class ackermann {
    public static void main(String[] args) {
        int num = Integer.parseInt(args[0]);
        System.out.println("Ack(3," + num + "): " + Ack(3, num));
    }
    public static int Ack(int m, int n) {
        return (m == 0) ? (n + 1) : ((n == 0) ? Ack(m-1, 1) :
                         Ack(m-1, Ack(m, n - 1)));
    }
}