Don't over complicate it. Given two number ranges, of UTC timestamps, determine if they overlap. I think you know where to start with that.
Re:How to Interview Engineers
by throwaway29292 on Wednesday June 28, 2017 @02:53AM
(#14652177)
I'd probably go for 4 if() checks, some 'less than'/'greater than'/'&&' checks should do it.
I'm sure good at fighting database fires though.
This probably is at the heart of the answer to the question "how could this programmer with such a long resume have botched this interview so badly?" It would be insane to believe they've never added value to any organization and have just been coasting along all this time. Maybe your interview sucks and isn't good at finding value.