[_mulder_]

A great response would be to just say "hold on", whip out your phone and Google the answer, show it to them and finish up with "How long did it take your other candidates to complete that task? next..."

Point being, you're demonstrating initiative and, that old cliche, thinking outside the box. Think Will Smith in Men In Black.

Some interviewers might be impressed with your lateral thinking, others might be annoyed at your attempt to be a 'smart ass' and avoid the intention of the question. But that's always the problem with these type of interview questions, it depends so much on the expectations of the interviewer.

[JonnieCache]

I think it would be funnier to silently transcribe the code from the phone to the whiteboard, and then just sit back down and look at them while you wait for a response.

[colanderman]

My response would be, "OK, walk me through the code, show me how and why it works, or if it doesn't (code from teh Internets is buggy), fix it." Anything higher than a junior position requires maintaining code as much as, or more than, writing it.

Maybe this points to a better class of interview questions: the interviewer supplies the broken algorithm, the interviewee supplies the bugfix.

[dllthomas]

"Anything higher than a junior position requires maintaining code as much, or more than, writing it."

I think that applies to junior positions, too.

[colanderman]

You're correct, but generally when critical thing X is broken and you need it working for the customer, you give it to your more experienced devs, not the college intern.

[dllthomas]

True, but when I'm in a more senior position, we're less often in a situation where critical thing X is broken.

[jiggy2011]

"oh, you can use google. Surely none of the other candidates could think of that"

[TheOtherHobbes]

The professionals use StackOverflow.

[angersock]

If an interviewee had the stones to try that in an interview, I'd probably have to at least give them a golf clap.