Made an interview mistake. Should I try to correct after the fact?

Question

Ever been in a situation where you were in an interview, and realized immediately afterwards (after the nervousness wore off) that you did something wrong?

I had a phone interview today. I was asked an n-ary tree problem, and coded an algorithm that used a space overhead, then a different algorithm with no space overhead. However, my solution was inefficient, since I traversed the tree top-down rather than bottom-up.

The interviewer said I did a good job, but I'm still wondering if he noticed and marked down for my choice of implementation. Should I follow up with an email correcting myself, or just let it and avoid making things worse?

Answer 1

I've done that before, and sent an email with what I thought was the right answer. I think the extra effort (and showing I actually cared) helped me get the job. Go for it.

Answer 2

I'd let it go (unless maybe if it was the only question - and if I really wanted the job) ... certainly if you think you made a general 'good' impression (don't want to ruin that now then)).

They could think you just looked it up afterwards. Or it could be conceived as being a little 'pushy' (depends on who you're dealing with, of course).

Every candidate gets one 'even' chance at an interview (in fixed conditions) ; it could be conceived as trying to mess with these 'conditions' under which the candidates skills were tested (they now it's 'instantaneous sampling').

Answer 3

By all means, yes. People make mistakes, there's nothing wrong with that. Being able to admit that you made one and trying to correct it, that makes quite a good impression, at least in Western civilization (you haven't mentionned where you're from).

Answer 4

Let's see. Assume that the interviewer knows that you could have done better.

• you contact them

  • they think that you have looked it up because
    • you are genuinely interested in the problem - wow, the guy hammers a problem until it's solved
    • you want the job - wow, here is a guy who really wants the job
  • they think that you thought about it, because
    • you are genuinely interested in the problem - wow, the guy hammers a problem until it's solved
    • you want the job - wow, here is a guy who really wants the job

  ...

• you don't contact them

  • because you think your first solution is the best you can achieve
  • because you find it would be too much effort
  • because your pride is more valuable to you than getting the job done properly
  • because you don't care

  ...

It is vastly subjective and incomplete, but I can find many more positive things in the first and many negative things in the second list.

The only problematic case is if they think that you really, desperately need the job - e.g. when negotiating salary.

You can still rectify it then - and lessen the likeliness of this happening by properly communicating your (new) solution in the first place.

Answer 5

When you send your thank-you note (you are sending/e-mailing a thank-you note, aren't you?), you should mention that right after you hung up, you realized your solution was inefficient, since you traversed the tree top-down rather than bottom-up, but that's the kind of analysis you enjoy and would make you a good blah blah blah.

'nuff said.

Answer 6

I've been in that situation. In the evening, when I sent my 'thank you for interviewing me' email, I answered a few questions that I totally bombed as well as one I had gotten wrong.

I ended up getting the job, and at my one year review my boss had told me that if I hadn't done that, he wouldn't have offered me.

So, in the end I'd say that it can't hurt, but it may help you :)