(递归) 汉诺塔问题 lintcode 169

class Solution {
public:
    /**
     * @param n: the number of disks
     * @return: the order of moves
     */
    vector<string> res;
    vector<string> towerOfHanoi(int n) {
        // write your code here
        move(n, "A", "B", "C");
        return res;
    }
    void move(int n, string from, string buffer, string to){
        if(n==1){
            string s = "from "+ from + " to " + to ;
            res.push_back(s);
        }
            
        else{
            move(n-1, from, to, buffer);
            move(1, from, buffer, to);
            move(n-1, buffer, from, to);
        }
    }
};