Given an array of strings *strs*, group the anagrams together. You can return the answer in any order. An **anagram** is a word formed by rearranging the letters of another word.
strs = [array of strings]
List<List<String>> (groups of anagrams)
Example 1:
Input:
strs = ["eat","tea","tan","ate","nat","bat"]
Output:
[[ate,eat,tea],[bat],[nat,tan]]
Explanation:
Anagrams are grouped together; order of groups or words within groups can vary.
Example 2:
Input:
strs = [""]
Output:
[[]]
Explanation:
Single empty string forms one group.