Hey y'all, sharing a recent interview experience on behalf of anonymous. This ain't me but I hope these data points help. OP was asked the variants, not the OG - so, I linked the variant posts below.

Q1: LC199 Binary Tree Right Side View
Variant: what if you had to return the left and right side views? It was noted that the view could be stored the left- and right side views separately. I haven't ever heard of anyone returning a Tuple of Lists but guess it was acceptable.

Q2: LC1539 Kth Missing Positive Number
Variant: What if you had to return the missing number from the leftmost element?
Candidate solvede it using binary search and made further optimizations (not sure what they were though).

I don't know information beyond this, but if you have pressing questions, I can ask anonymous.

Good luck with your studies!