Applied directly on the website and had an answer from a recruiter the same day.

Had a first phone interview to get a general feel of my background. A few weeks later, I had a technical phone interview. Since I was in London, I came on-site 3 days later for a 3-hour interview (3 times 1 hour).

Given a set of events [e1, e2, e3, ... , eN] occurring at given times and a set of timeframes [t1, t2, .., tM], each having a start timestamp and an end timestamp, give an algorithm for each event the number of timeframes it occurs within (whiteboard, no code).

Write code on the whiteboard to iterate through a tree in postorder traversal. First recursively, and then iteratively.

Given a set of cabs navigating within a city, where would be the best place for all of them to meet?