update snippets 16-31

snippets/differenceWith.md

@@ -6,5 +6,8 @@ Use `Array.filter()` and `Array.find()` to find the appropriate values.
 
 ```js
 const differenceWith = (arr, val, comp) => arr.filter(a => !val.find(b => comp(a, b)))
-// differenceWith([1, 1.2, 1.5, 3], [1.9, 3], (a,b) => Math.round(a) == Math.round(b)) -> [1, 1.2]
+```
+
+```js
+differenceWith([1, 1.2, 1.5, 3], [1.9, 3], (a,b) => Math.round(a) == Math.round(b)) -> [1, 1.2]
 ```