leetcode 无重复字符串的排列和组合

1.题目要求:

2.题目代码：

class Solution {
public:vector<string> result;string str;//利用回溯去解决此问题void backtricking(string S,vector<bool>& used){if(str.size() == S.size()){result.push_back(str);}//用used去掉重复的排列与组合for(int i = 0;i < S.size();i++){if(used[i] == false){str.push_back(S[i]);used[i] = true;backtricking(S,used);str.pop_back();used[i] =false;}else{continue;}}}vector<string> permutation(string S) {vector<bool> used;used.resize(S.size(),false);backtricking(S,used);return result;}
};