Group Anagrams

Given an array of strings strs, group the anagrams together and return the groups in any order. Strings within each group may appear in any order.

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Example 1

Input: strs = ["eat", "tea", "tan", "ate", "nat", "bat"]
Output: [["eat","tea","ate"], ["tan","nat"], ["bat"]]
Explanation: The first three are anagrams of each other, as are "tan" and "nat". "bat" has no anagram partner.

Example 2

Input: strs = [""]
Output: [[""]]
Explanation: Single empty string forms its own group.

Example 3

Input: strs = ["a"]
Output: [["a"]]
Explanation: Single character string forms its own group.

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Constraints

• 1 <= strs.length <= 10^4
• 0 <= strs[i].length <= 100
• strs[i] consists of lowercase English letters.