How to answer tricky whiteboard questions

Recorded May 2nd 2020 – watch the full episode on YouTube.

If we have a question where you're thinking, well, that's a question that is very hard, or trying to catch me out. What's your advice to handle those kind of tricky questions that come at you?

Sean Allen: So again, I don't know if I'm the right person to give advice. Because every time they've come at me, it's been rough.

I can give an example of a question here that blew my mind at the time. I won't say the company. It was a very large company. You have an infinite chess board, you have a knight. A knight can only move in an L shape. You pass in point A, you pass in point B, figure out the smallest number of moves to get from point A to point B again, not on a limited chess board, on an infinite chess board.

And I was like, what? So I was like deer in the headlights. I don't even know where to start. This is one of those embarrassing times, by the way.

So yeah, these whiteboard questions have been the, what do you call it? My Achilles heel, if you will. They've always tripped me up. It's because I don't have the CS background and I didn't put in the proper time to learn and study, like I mentioned in the previous questions. I always tried to cram it in last minute, because that's how I've done every academic thing in my life, and not the way to do it in this case.

Paul Hudson: What would you say is the value or role of whiteboard interviews? Is there a value to them?

Sean Allen: This is probably one of the biggest debates out there. I tend to fall on, and this is obviously through my lens, so of course I'm going to tend to fall on the side of, I don't think there's much value in them. There's plenty of studies and obviously Google, Apple, all these big companies do it that way. So there's some reason. And they'll even admit by the way, they have a lot of false negatives. They'll say we've turned down so many great programmers due to this stuff, and they've just made the choice that we're okay with false negatives.

When I did the Google interview and got turned away, they said, “oh, don't worry. This is your first time. It usually takes people four or five times to get into Google. It's not uncommon.” But anyway, through my lens, I don't think they're useful, but I'm not going to act like that's the definitive answer.

“I did my best for our take home project at Aluna to make sure I talked to all the candidates. Because I know what it feels like to put work into something or an interview, and you just get the sorry, we're going to go in another direction email, with no feedback at all.”

Paul Hudson: There's a statement here from a listener who says, “don't forget to provide all candidates feedback.” Do you get that much? Do you get good feedback about your take home tests or your interviews? They provide details to you about what we were weak on, what you're strong on. Was it more sort of gut instinct?

Sean Allen: No. I mean, some do, some don't. I did my best for our take home project at Aluna to make sure I talked to all the candidates. Because I know what it feels like to put work into something or an interview, and you just get the sorry, we're going to go in another direction email, with no feedback at all.

Some companies do give you feedback, some don't. And the reason some don't, I can't justify this, I don't know. But they say there are legal reasons. I don't know. Sometimes they give too much information, and then a candidate, that's what they say. I'm sure they've had a bad experience in the past, but yeah, I like to give the candidates feedback, just to help them out because I know what it's like to get rejected, and it sucks.

Because oftentimes people are applying to 50 companies, getting rejected by 45 of them. It's tough getting those just blanket rejection emails. So I try to let them know what they can improve. Right? Just have some empathy.

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