Thank you. I'd be pretty annoyed in this interview. Surely my potential employer would be more interested in having me apply my twenty years of real-world experiences to what I learned in CS240.
Not sure why you'd be annoyed? What I'm trying to gauge in my interviews is their real-world experience (not their academic CS knowledge). That's part of the reason I find my line of questioning helpful: I don't penalize them for a "wrong" answer, but more how they think about it. Then we can discuss parallelization, map-reduce techniques, profiling and measurement, and so on.