Shorten algorithm

snippets/shuffle.md

@@ -5,16 +5,13 @@ Randomizes the order of the values of an array, in place.
 Uses the Fisher-Yates algoritm to reorder the elements of the array, based on the [Lodash implimentation](https://github.com/lodash/lodash/blob/b2ea6b1cd251796dcb5f9700c4911a7b6223920b/shuffle.js)
 
 ```js
-const shuffle = (arr = []) => {
-  let i = -1;
-  const lastIndex = arr.length - 1;
-  while (++i < arr.length) {
-    const rand = i + Math.floor(Math.random() * (lastIndex - i + 1));
-    const value = arr[rand];
-    arr[rand] = arr[i];
-    arr[i] = value;
+const shuffle = ([...arr]) => {
+  let m = arr.length;
+  while (m) {
+    const i = Math.floor(Math.random() * m--);
+    [arr[m], arr[i]] = [arr[i], arr[m]];
   }
-  return arr
+  return arr;
 };
 // shuffle([1,2,3]) -> [2,3,1]
 ```