First, they approached me through an external recruiter.

Then, one of their own HR managers called me via Skype and asked a battery of theoretical IT questions.

Lastly (where they kicked me out), I had an interview with one of their engineers. I had about 30 minutes to solve a problem in CoderPad. Although I believe I solved it, I probably wasn't convincing enough in terms of efficiency.

Given an array of strings with commit IDs and a predicate isBuggy that returns if a single commit is buggy, write a program that finds the first buggy commit.

• When a commit is buggy, we assume that all its children are buggy.
• When a commit is not buggy, we assume that all its ancestors are not buggy.

After solving it, I had to describe its time and spatial complexity and how I would choose the test cases.