Programming challenges I use to hire Programmers
For.e.g <a href="https://projecteuler.net/problem=1" target="_blank" rel="nofollow noopener noreferrer">#1 Multiples of 3 or 5 - Project Euler</a>
This is the simplest problem there. Check out some of the other problems, it is the perfect test for comp. sci. engineers, since not only does this test your logic writing skills but also it tests your knowledge of your favorite programming language!!