car.mjs, code solution for https://www.codewars.com/kata/buying-a-car/train/javascript
array-diff.mjs, code solution for https://www.codewars.com/kata/523f5d21c841566fde000009
playing-with-digits.mjs, code solution for https://www.codewars.com/kata/5552101f47fc5178b1000050