feat: adds shuffle

Author: Kevin Hermawan

README.md

@@ -152,6 +152,21 @@ console.log(result); // [2, 3, 4, 5, 1]
 >
 > O(n), where n is the length of the array.
 
+#### [shuffle](/src/shuffle.ts)
+
+Shuffles the element of the array. Implements [Fisher-Yates shuffle Algorithm](https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle).
+
+```ts
+import { shuffle } from 'enhanced-array';
+
+const result = shuffle([1, 2, 3, 4, 5]);
+console.log(result); // [5, 3, 2, 4, 1] (shuffled)
+```
+
+> **Time complexity:**
+>
+> O(n), where n is the length of the array.
+
 #### [swap](/src/swap.ts)
 
 Exchanges the element at the specified indices of the array.

src/shuffle.ts

@@ -0,0 +1,11 @@
+export function shuffle<T>(array: T[]) {
+  const result = array;
+
+  for (let i = result.length - 1; i > 0; i -= 1) {
+    const randomIndex = Math.floor(Math.random() * (i + 1));
+
+    result.splice(i, 1, result.splice(randomIndex, 1, result[i])[0]);
+  }
+
+  return result;
+}

test/shuffle.test.ts

@@ -0,0 +1,11 @@
+import { describe, expect, it } from 'vitest';
+
+import { shuffle } from '../src/shuffle';
+
+describe('shuffle', () => {
+  it('shuffles element correctly', () => {
+    const result = shuffle([1, 2, 3, 4, 5]);
+
+    expect(result).to.not.eql([1, 2, 3, 4, 5]);
+  });
+});