The interview process consisted of three stages.

1. The first stage was a phone call with HR. We exchanged general information; I explained who and what I am, and they described the job and the upcoming interview.

2. The second stage was an online session with a technical interviewer. They asked me to solve a relatively simple task online and explain my solution. It was straightforward.

3. The final stage involved an in-person interview at their Prague office. They provided assistance with the visa process and booked/paid for my airplane tickets and hotel. The office was very nice. The interview lasted four hours, and I met with four high-profile Microsoft employees who are seriously involved in the development of Visual Studio and .NET. Each interviewer asked general questions to test my soft skills and presented coding problems to solve on a whiteboard. Writing on the whiteboard was the most uncomfortable part. Some tasks were quite difficult, while others were somewhat tricky. The interviewers were very friendly and nice, and it was a pleasure to meet them.

How to refactor recursive calls to avoid possible stack overflow?