【LeetCode】49. Group Anagrams

Given an array of strings, group anagrams together.

For example, given: ["eat", "tea", "tan", "ate", "nat", "bat"], 
Return:

[
  ["ate", "eat","tea"],
  ["nat","tan"],
  ["bat"]
]

解法1：

把含有相同字母的字符串分之同一组，对每组的值sorted

class Solution(object):
    def groupAnagrams(self, strs):
        """
        :type strs: List[str]
        :rtype: List[List[str]]
        """
        return [sorted(x) for _,x in itertools.groupby(sorted(strs, key=sorted),key=sorted)]

解法2：

把每一个含有相同字母的字符串散列到同一个key，然后对每个value排序即得。

class Solution(object):
    def groupAnagrams(self, strs):
        """
        :type strs: List[str]
        :rtype: List[List[str]]
        """
        dd = collections.defaultdict(list)
        for s in strs:
            dd[tuple(sorted(s))].append(s)
        return map(sorted, dd.values())