49\. Group Anagrams

Medium

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:**

*   <code>1 <= strs.length <= 10<sup>4</sup></code>
*   `0 <= strs[i].length <= 100`
*   `strs[i]` consists of lowercase English letters.