49 Group Anagrams

1 题目

Given an array of strings, group anagrams together.

2 尝试解

class Solution {
public:
    vector<vector<string>> groupAnagrams(vector<string>& strs) {
        map<string,vector<string>> dic;
        for(int i = 0; i < strs.size(); i++){
            string temp = strs[i];
            sort(temp.begin(),temp.end());
            if(dic.count(temp) == 0){
                vector<string> temp_set;
                temp_set.push_back(strs[i]);
                dic[temp] = temp_set;
            }
            else{
                dic[temp].push_back(strs[i]);
            }
        }
        map<string,vector<string>>::iterator item;
        item = dic.begin();
        vector<vector<string>> result;
        while(item != dic.end()){
            result.push_back(item->second);
            item++;
        }
        return result;
    }
};

3 标准解

class Solution {
public:
    vector<vector<string>> groupAnagrams(vector<string>& strs) {
        unordered_map<string, vector<string>> mp;
        for (string s : strs) {
            string t = s; 
            sort(t.begin(), t.end());
            mp[t].push_back(s);
        }
        vector<vector<string>> anagrams;
        for (auto p : mp) { 
            anagrams.push_back(p.second);
        }
        return anagrams;
    }
};