Add solution #384

Author: JoshCrozier

README.md

@@ -281,6 +281,7 @@
 378|[Kth Smallest Element in a Sorted Matrix](./0378-kth-smallest-element-in-a-sorted-matrix.js)|Medium|
 380|[Insert Delete GetRandom O(1)](./0380-insert-delete-getrandom-o1.js)|Medium|
 383|[Ransom Note](./0383-ransom-note.js)|Easy|
+384|[Shuffle an Array](./0384-shuffle-an-array.js)|Medium|
 387|[First Unique Character in a String](./0387-first-unique-character-in-a-string.js)|Easy|
 389|[Find the Difference](./0389-find-the-difference.js)|Easy|
 392|[Is Subsequence](./0392-is-subsequence.js)|Easy|

solutions/0384-shuffle-an-array.js

@@ -0,0 +1,40 @@
+/**
+ * 384. Shuffle an Array
+ * https://leetcode.com/problems/shuffle-an-array/
+ * Difficulty: Medium
+ *
+ * Given an integer array nums, design an algorithm to randomly shuffle the array.
+ * All permutations of the array should be equally likely as a result of the shuffling.
+ *
+ * Implement the Solution class:
+ * - Solution(int[] nums) Initializes the object with the integer array nums.
+ * - int[] reset() Resets the array to its original configuration and returns it.
+ * - int[] shuffle() Returns a random shuffling of the array.
+ */
+
+/**
+ * @param {number[]} nums
+ */
+var Solution = function(nums) {
+  this.original = [...nums];
+  this.result = [...nums];
+};
+
+/**
+ * @return {number[]}
+ */
+Solution.prototype.reset = function() {
+  this.result = [...this.original];
+  return this.result;
+};
+
+/**
+ * @return {number[]}
+ */
+Solution.prototype.shuffle = function() {
+  for (let i = this.result.length - 1; i > 0; i--) {
+    const j = Math.floor(Math.random() * (i + 1));
+    [this.result[i], this.result[j]] = [this.result[j], this.result[i]];
+  }
+  return this.result;
+};