import java.util.*; public class Solution { ArrayList<String> list = new ArrayList<>(); public ArrayList<String> getSolution(int n) { // write code here String A = "left"; String B = "mid"; String C = "right"; HanTower(A,B,C,n); return list; } public void HanTower(String A, String B, String C, int n){ if(n==1){ //递归停止条件 list.add("move from " + A + " to " + C); }else{ //将上面的盘子通过C移到B HanTower(A,C,B,n-1); //将最下面的盘子直接移到C list.add("move from " + A + " to " + C); //将移到B的盘子再通过A移到C HanTower(B,A,C,n-1); } } }