[elq]

indeed! Yet, in the interview I'm thinking of, he didn't even get this far.

poorly specified questions are very important to ask IMHO :)

[Ethan_Mick]

I would say this is actually a very important part of interviewing. When given vague requirements, see how they respond. Building something that is technically correct isn't as good as building what you actually want.

[zopppo]

I'm curious what language was he using?

[S4M]

Probably Python.