public void initialize() {
        no_of_clicks = 0;
        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 3; j++) {
                ar[i][j] = 0;
            }
        }
        for (int i = 0; i
                < 9; i++) {
            clicked[i] = 0;
        }
    }