feat(work): add solutions for LeetCode problems 217, 242, 189, and 49

work/Medium/Array/189.rotate-array.js

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+/*
+ * 189. Rotate Array
+ * Difficulty: Medium
+ * https://leetcode.com/problems/rotate-array/
+ * 
+ * ──────────────────────────────────────────────────
+ * 
+ * Given an integer array nums, rotate the array to the right by k
+ * steps, where k is non-negative.
+ * 
+ *  
+ * 
+ * Example 1:
+ * 
+ * Input: nums = [1,2,3,4,5,6,7], k = 3
+ * Output: [5,6,7,1,2,3,4]
+ * Explanation:
+ * rotate 1 steps to the right: [7,1,2,3,4,5,6]
+ * rotate 2 steps to the right: [6,7,1,2,3,4,5]
+ * rotate 3 steps to the right: [5,6,7,1,2,3,4]
+ * 
+ * Example 2:
+ * 
+ * Input: nums = [-1,-100,3,99], k = 2
+ * Output: [3,99,-1,-100]
+ * Explanation: 
+ * rotate 1 steps to the right: [99,-1,-100,3]
+ * rotate 2 steps to the right: [3,99,-1,-100]
+ * 
+ *  
+ * 
+ * Constraints:
+ * 
+ * 	• 1 <= nums.length <= 10^5
+ * 
+ * 	• -2^31 <= nums[i] <= 2^31 - 1
+ * 
+ * 	• 0 <= k <= 10^5
+ * 
+ *  
+ * 
+ * Follow up:
+ * 
+ * • Try to come up with as many solutions as you can. There are at
+ * least three different ways to solve this problem.
+ * 
+ * 	• Could you do it in-place with O(1) extra space?
+*/
+
+/**
+ * @param {number[]} nums
+ * @param {number} k
+ * @return {void} Do not return anything, modify nums in-place instead.
+ */
+var rotate = function(nums, k) {
+    
+};

work/Medium/Array/49.group-anagrams.js

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+/*
+ * 49. Group Anagrams
+ * Difficulty: Medium
+ * https://leetcode.com/problems/group-anagrams/
+ * 
+ * ──────────────────────────────────────────────────
+ * 
+ * Given an array of strings strs, group the anagrams together. You can
+ * return the answer in any order.
+ * 
+ *  
+ * 
+ * Example 1:
+ * 
+ * Input: strs = ["eat","tea","tan","ate","nat","bat"]
+ * 
+ * Output: [["bat"],["nat","tan"],["ate","eat","tea"]]
+ * 
+ * Explanation:
+ * 
+ * 	• There is no string in strs that can be rearranged to form "bat".
+ * 
+ * • The strings "nat" and "tan" are anagrams as they can be rearranged
+ * to form each other.
+ * 
+ * • The strings "ate", "eat", and "tea" are anagrams as they can be
+ * rearranged to form each other.
+ * 
+ * Example 2:
+ * 
+ * Input: strs = [""]
+ * 
+ * Output: [[""]]
+ * 
+ * Example 3:
+ * 
+ * Input: strs = ["a"]
+ * 
+ * Output: [["a"]]
+ * 
+ *  
+ * 
+ * Constraints:
+ * 
+ * 	• 1 <= strs.length <= 10^4
+ * 
+ * 	• 0 <= strs[i].length <= 100
+ * 
+ * 	• strs[i] consists of lowercase English letters.
+*/
+
+/**
+ * @param {string[]} strs
+ * @return {string[][]}
+ */
+var groupAnagrams = function(strs) {
+  let sorted = strs.map(str => str.split("").sort().join(""));
+  let anagrams = {};
+
+  for (let i = 0; i < strs.length; i++){
+    if(!anagrams[sorted[i]]){
+      anagrams[sorted[i]] = [strs[i]]
+    }else{
+      anagrams[sorted[i]].push(strs[i])
+    }
+  }
+
+  return Object.values(anagrams);
+};