题解 | #字符串的排列#

class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param str string字符串 
     * @return string字符串vector
     */
    void RecHelper(vector<string>& res, string& cur, vector<int>& visited, string& str)
    {
        if(cur.size()==str.size())
        {
            res.push_back(cur);
            return;
        }
        for(int i=0; i<str.size(); i++)
        {
            if(visited[i]==1)
                continue;
            if(i>0 && str[i-1]==str[i] && visited[i-1]==1)
                    continue;
            cur.push_back(str[i]);
            visited[i]=1;
            RecHelper(res, cur, visited, str);
            visited[i]=0;
            cur.pop_back();
        }
    }
    vector<string> Permutation(string str) {
        vector<string> res;
        string cur="";
        vector<int> visited(str.size(), 0);
        sort(str.begin(), str.end());
        RecHelper(res, cur, visited, str);
        return res;
    }
};