class Solution {
public:
    vector<vector<string>> groupAnagrams(vector<string>& strs) {
        //总结：分组做法：建立这样的映射 map<string, vector<string>> mp！！！
        map<string, vector<string>> mp; //映射：键为排序后的字符串，值为vector
        vector<vector<string>> result;

        string temp;
        for (int i = 0; i < strs.size(); i++){
            temp = strs[i];
            sort(strs[i].begin(), strs[i].end()); //先排序
            mp[strs[i]].push_back(temp);
        }
        for (map<string, vector<string>>::iterator it = mp.begin(); it != mp.end(); it++){
            result.push_back(it -> second);
        }
        return result;
    }
};