Group Anagrams

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

An Anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.

Example 1:

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

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.

Source: https://leetcode.com/problems/group-anagrams/

Leetcode Difficulty: Medium

Asked in: Facebook Amazon ,Apple  Netflix Google

Code:

    def groupanagrams(self, strs):
        """
        strs: List[str]
        return: List[List[str]]
        """
        if len(strs)==0: return [[""]]
        elif len(strs)==1: return [[strs[0]]]
        
        ans = collections.defaultdict(list)
        for s in strs:
            ans[tuple(sorted(s))].append(s)
        return ans.values()

Thought Process / Explanation:

The keyword "grouping" hints me to use a dictionary where key will be a common representation of strings and value be their original form. Also, we know that sorted anagrams represent the exact same string.

Thank You!