LeetCode 49. 字母异位词分组

给定一个字符串数组，将字母异位词组合在一起。字母异位词指字母相同，但排列不同的字符串。

示例:

输入: ["eat", "tea", "tan", "ate", "nat", "bat"]输出:
[
  ["ate","eat","tea"],
  ["nat","tan"],
  ["bat"]
]

?  https://leetcode-cn.com/classic/problems/group-anagrams/description/

异位词虽然字符的排序被打乱了,但是对其排序之后的结果都是一样的。例如: ate 和 tae 排序后都是 aet

排序 + 哈希

class Solution:
    def groupAnagrams(self, strs: List[str]) -> List[List[str]]:
        ans = dict()
        res = []
        for i in strs:
            strr = sorted(i)  # 字符串排序之后返回一个list
            st = ''
            for j in strr:
                st += j
            if st not in ans:
                ans[st] = []
                ans[st].append(i)
            else:
                ans[st].append(i)
        for i in ans:
            res.append(ans[i])
        return res