The first conversation was with an internal recruiter. The next one was a coding interview.

The coding exercise involved one of the team members. They presented the first exercise, and after it was completed, the second exercise was presented. You had your choice of programming language, but you were not allowed to compile or run your solution. The interviewer evaluated your logic to ensure it was correct. Therefore, syntactic perfection was not required; the solution needed to demonstrate that it would arrive at the correct result. Intellisense was available, however.

• First Exercise: Given a list of appointments for the day, each with a start time, end time, and title, return a list of contiguous busy blocks. This is analogous to a consultant's office with scheduled appointments, where the goal is to determine when the consultant is busy versus when they can take lunch.
• Second Exercise: Given a list of pairs representing CI build jobs, where each pair consists of a job and a job it depends on, return a list of jobs in a build order that respects the dependency constraints. (I was informed that it was acceptable to assume the data was valid and not to worry about circular dependencies or other problematic input.)

I successfully developed working solutions for both exercises (meaning both the interviewer and I agreed they would function correctly). However, the algorithm for the second exercise was not as efficient as it could have been. I clearly stated at the beginning that I was sure a more efficient solution existed, but I opted for a straightforward approach to get something working first, with the intention of optimizing later. We then discussed a more optimal solution and how it would work, talking it through without writing any code.

A few days later, I received a rejection email, indicating no further progression in the interview process.

Given a simple set of calendar time appointments in a day, find and return all contiguous blocks of busy time.

Given a list of build jobs and their dependencies (as pairs), return the order in which jobs are to be built that would satisfy dependencies.