Added array shuffle

snippets/shuffle-array-values.md

@@ -0,0 +1,12 @@
+### Shuffle array values
+
+Create an array of random values by using `Array.map()` and `Math.random()`.
+Use `Array.sort()` to sort the elements of the original array based on the random values.
+
+```js
+const shuffle = arr => {
+  let r = arr.map(Math.random);
+  return arr.sort((a,b) => r[a] - r[b]);
+}
+// shuffle([1,2,3]) -> [2, 1, 3]
+```