Group Anagrams
Given an array of strings strs, group all anagrams together into sublists. You may return the answer in any order.
An anagram is a string that contains exactly the same characters as another string, but the order of the characters can be different.
Example 1:
Input: strs = ["eat","tea","tan","ate","nat","bat"] Output: [["eat","tea","ate"],["tan","nat"],["bat"]]
Example 2:
Input: strs = [""] Output: [[""]]
Example 3:
Input: strs = ["a"] Output: [["a"]]
Recommended time and space complexity
You should aim for a solution with O(n * k * log(k)) time complexity and O(n * k) space complexity, where n is the number of strings and k is the maximum length of a string.
Hint 1
How can you determine if two strings are anagrams? What do all anagrams of the same string have in common?
Hint 2
Can you transform each string so that all anagrams produce the same result? Think about sorting characters.
Hint 3
Sorted characters of anagrams form the same string. Use this string as a key in a hash table to group anagrams.