If you are looking for 'computer science topic' knowledge, I don't think you should search a site 1) geared heavily towards math and 2) seeks to challenge participants (unlike cryptopals, which provides a guide) in the first place.
That's a really good point actually. Perhaps Project Euler has a CS association where it doesn't really belong because it's often mentioned in CS/programming challenges threads, even if it's not intended to be the focus of the exercises.
