We have an initial Hacker Rank 'filter', that if you don't pass that, we don't even do an interview. A few weeks ago we interviewed someone who passed that filter very well. But in the interview, it was really below par. Not even the basics were understood. So I'm very skeptical about these kinds of homework where they could get help.

What I currently do is go through a very simple coding example that I wrote (very generic). Then we go through the code and I ask questions like "can you explain what this line is doing", or "If I move this line over here, is the behavior still the same", etc. Some bugs are in there and I ask what is going wrong and how to solve them.

Not ideal, but the problem is that nothing really is :(.