The recruiter was pleasant and persistent, and patient. The first interview was a phone screening on-site. It was decent; the interviewer was professional and pleasant. The second day involved five interviews in a row with a lunch break. The food was great, as was the companionship. The interviews weren't easy but were fair.

Given UTF-8 encoding rules, given a byte array, determine if it's a valid string.

System Design: Design a system that, given a point on Earth, will return the highest building within a 100m radius. The question was developing.

Start by assuming everything fits in memory. Then, assume not everything fits. Then, use several machines. Then, consider what happens when one is down. The purpose is to answer as quickly as possible, but you have preprocessing time.

As a follow-up, what if you want to update the data?

Design a regular expression matching class. The emphasis is on design and then coding.