> I thought I was done, then the interviewer said she would go go copy my code and compile it after the interview to see if I was right, which blew my mind.
I've been interviewing at Google for nine years and have never done this. I generally don't think it's fair to ding a candidate for something I don't notice in an interview, where I'm at a huge advantage. If it looks right to me then that's good enough.
But that said, I have often asked questions similar to what you describe. You have to write code in the shared doc because hiring committees want to see it - fair to blame the process for that, but not the interviewer. I actually appreciate this for a couple reasons:
* It levels the playing field a bit, in the sense that code is more objective than an interviewer's notes on how a conversation went (especially for people who aren't native English speakers)
* I sometimes find that candidates who communicate well struggle to turn their ideas info code. Other times, someone's communication and solution are kind of average, but then they use all the little things I like seeing (defaultdict(set), zip, etc. in Python). Lots of people claim to be very experienced programmers; seeing how comfortable and fluent someone is when actually writing code is a strong signal. If you don't like the focus on data structures and algorithms that you haven't thought about since college, you should probably appreciate the coding part.