LeetCode 49. 字母异位词分组

题目链接：https://leetcode.cn/problems/group-anagrams/

思路如下：

输入：strs = [“eat”, “tea”, “tan”, “ate”, “nat”, “bat”]

对每个字符串进行排序：strs = [“aet”, “aet”, “ant”, “aet”, “ant”, “abt”]

如果排序后的字符串相同，则将它们归为同一组：[[“bat”],[“nat”,“tan”],[“ate”,“eat”,“tea”]]

C++代码如下：

class Solution {
public:
    vector<vector<string>> groupAnagrams(vector<string>& strs) {
        unordered_map<string, vector<string>> str2vec;
        for (auto& str : strs) {
            auto tmp = str;
            sort(tmp.begin(), tmp.end());
            str2vec[tmp].push_back(str);
        }
        vector<vector<string>> res;
        for (auto& item : str2vec) {
            res.push_back(item.second);
        }
        return res;
    }
};