java学习p226

public class a1 {
    public static void main(String[] args) {
        Tower tower = new Tower();
        tower.move(3, 'a', 'b', 'c');
    }
}

class Tower {
    public void move(int num, char a, char b, char c) {
        if (num == 1) {
            System.out.println(a + " -> " + c);
        }
        else {
            move(num - 1, a, c, b);
            System.out.println(a + " -> " + c);
            move(num - 1, b, a, c);
        }
    }
}