One thing I’ve seen and that was actually done in my interview where I currently work, is that if they solve the given problem to fast they keep adding “twists” to the problem just to see how far they could go.
It would be questions like,
What if the user presses this?
What if I do this?
Just trying to poke holes on what you did and see how you figure out a solution for these new bug/requirements that were thought of on the spot.
This is how I structure my interview questions. They come in phases, and I can always extend it if need be. I know about where people should make it to, and where top people make it to.
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