“When I was asked to write an image filtration algorithm I spent the first 15 minutes just to understand the question. I ran out of time. ”
I have been through few of these, I just assume that there are people out there who can understand and code up the question asked within 15 min. Those are the people this company is looking for. Not you and me.
It's a form of "guess the teacher's answer". I was once observer to a committee that rejected a candidate that came up with a more efficient and correct answer than the interviewer was looking for. I couldn't argue against it because I had recommended the candidate.