leetcode 49. 字母异位词分组

class Solution {
public:
    vector<vector<string>> groupAnagrams(vector<string>& strs) {
        vector<vector<string> > res;
        vector<string>cpy=strs;
        map<string,int> mp;int k=0;
        for(int i=0;i<strs.size();i++){
                sort(strs[i].begin(),strs[i].end());
                if(!mp.count(strs[i])){
                    mp[strs[i]]=k++;//cout<<mp[strs[i]]<<endl;
                }
                       
        }
        for(int i=0;i<strs.size();i++){
            if(res.size()<k)
                res.push_back({});
            res[mp[strs[i]]].push_back(cpy[i]);
        }
        return res;
    }
};

class Solution {
public:
    vector<vector<string>> groupAnagrams(vector<string>& strs) {
        vector<vector<string> > res;
        unordered_map<string,string> mp;int k=0;
        unordered_map<string,int> mp2;
        for(int i=0;i<strs.size();i++){
            string ex="00000000000000000000000000";
            for(int j=0;j<strs[i].size();j++){
                ex[strs[i][j]-‘a‘]+=1;
            }
            //cout<<ex<<endl;
            mp[strs[i]]=ex;
            if(!mp2.count(ex))
                mp2[ex]=k++;
        }
        for(int i=0;i<strs.size();i++){
            if(res.size()<k)
                res.push_back({});
            res[mp2[mp[strs[i]]]].push_back(strs[i]);
        }
        return res;
    }
};