update snippets 0-All

snippets/symmetricDifference.md

@@ -8,6 +8,9 @@ Create a `Set` from each array, then use `Array.filter()` on each of them to onl
 const symmetricDifference = (a, b) => {
   const sA = new Set(a), sB = new Set(b);
   return [...a.filter(x => !sB.has(x)), ...b.filter(x => !sA.has(x))];
-};
-// symmetricDifference([1,2,3], [1,2,4]) -> [3,4]
+}
+```
+
+```js
+symmetricDifference([1,2,3], [1,2,4]) -> [3,4]
 ```