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49. Group Anagrams

Array Hash Table String Sorting

Problem - Group Anagrams

Medium

Given an array of strings strs, group the anagrams together. You can return the answer in any order.

 

Example 1:

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

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

Explanation:

  • There is no string in strs that can be rearranged to form "bat".
  • The strings "nat" and "tan" are anagrams as they can be rearranged to form each other.
  • The strings "ate", "eat", and "tea" are anagrams as they can be rearranged to form each other.

Example 2:

Input: strs = [""]

Output: [[""]]

Example 3:

Input: strs = ["a"]

Output: [["a"]]

 

Constraints:

  • 1 <= strs.length <= 104
  • 0 <= strs[i].length <= 100
  • strs[i] consists of lowercase English letters.

Solutions

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class Solution:
    def groupAnagrams(self, strs: List[str]) -> List[List[str]]:
        dic = defaultdict(list)

        for stri in strs:
            curr = ''.join(sorted(stri))
            dic[curr].append(stri)

        return list(dic.values())

Submission Stats:

  • Runtime: 9 ms (90.00%)
  • Memory: 20.6 MB (77.75%)