[rocqua]

There is a difference between "Questions" and "test questions with a known specific solution". One could argue (I would not) that the solution to a test question is an integral part of the question and therefor if the one can be protected by copyright, so can the other".

[ben_w]

While that would apply to simple maths questions — 16x16 is always 256 — I don’t see that applying to HackerRank programming challenges, where the challenges (last time I used it) are essentially “produce correct output from this mostly-secret input”, and they don’t even mind which language you use to do this, never mind what variable names you use.

[pseudalopex]

Is there any legal basis for that argument?

[RattleyCooper]

Nope

[chakkepolja]

At least in this case, there can be multiple correct answers using different approaches, in that case your theory leads to further confusion.

[nkrisc]

It such a question exists, surely it is the exception that proves the rule.