public class RandomWalker {
    public static void main(String[] args) {
        int r = Integer.parseInt(args[0]);
        int steps = 0;
        int x = 0;
        int y = 0;
        double ar;

        System.out.println("(" + x + ", " + y + ")");

        while ((Math.abs(x) + Math.abs(y)) < r) {
            ar = Math.random();

            if (ar < 0.25) x++;
            else if (ar < 0.50) x--;
            else if (ar < 0.75) y++;
            else if (ar < 1.00) y--;

            System.out.println("(" + x + ", " + y + ")");
            steps++;
        }
        System.out.println("steps = " + steps);
    }
}