Hanoi

递归解决 汉诺塔

 class Han{
     int num;
     int steps;
     Han(int num){
         this.num=num;
     }
     void total()
     {
         System.out.println("total="+steps);
     }
     void show(int i, int from, int des, String[] str)
     {
         int tmp = 3-from-des;//0+1+2=3
         if (i==2)
         {
             System.out.println(1+":"+str[from]+"->"+str[tmp]);
             System.out.println(2+":"+str[from]+"->"+str[des]);
             System.out.println(1+":"+str[tmp]+"->"+str[des]);
             steps+=3;
         }else
         {
             show(i-1, from, tmp, str);
             System.out.println(i+":"+str[from]+"->"+str[des]);
             show(i-1, tmp, des, str);
             steps+=1;
         }
     }
 } 

 public class HelloWorld{
     public static void main(String[] args) {
         Han h=new Han(5);//set numbers of member
         String[] str= {"A","B","C"};//three pillars
         h.show(h.num, 0, 2, str);//from pillar 0 to pillar 2
         h.total();//2^n-1
     }
 }