哈希表与字符串的相关题目-词语模式 同字符词语分组

class Solution {
public:
    vector<vector<string>> groupAnagrams(vector<string>& strs) {
          if(strs.empty()) return vector<vector<string>>{};

        vector<vector<string>> res;
        unordered_map<string, int> m;
        int cnt = 0;
        for(int i = 0; i < strs.size(); ++i)
        {
            string e = strs[i];
            sort(e.begin(), e.end());
            if(m.count(e))
            {
                res[m[e]].push_back(strs[i]);
            }
            else
            {
                m[e] = cnt++;
                res.push_back({strs[i]});
            }
        }
        return res;
    }
};