LeetCode-49-Group Anagrams

算法描述：

Given an array of strings, group anagrams together.

Example:

Input: ["eat", "tea", "tan", "ate", "nat", "bat"],
Output:
[
  ["ate","eat","tea"],
  ["nat","tan"],
  ["bat"]
]

Note:

• All inputs will be in lowercase.
• The order of your output does not matter.

解题思路：对字符串进行排序，然后用排序后的字符串做索引建立map。

    vector<vector<string>> groupAnagrams(vector<string>& strs) {
        vector<vector<string>> results;
        unordered_map<string,vector<string>> map;
        for(int i=0; i< strs.size(); i++){
            string temp = strs[i];
            sort(temp.begin(),temp.end());
            if(map.find(temp)==map.end()){
                vector<string> strtemp;
                map[temp] = strtemp;
            }
            map[temp].push_back(strs[i]);
        }
        for(auto m:map){
            results.push_back(m.second);
        }
        return results;
    }