I took a coding assessment, which was difficult, but they were clear that it wasn't expected to be completely finished within the time limit.

After this, there was a phone call that included a technical question, which was simple: just updating values in a process class.

Then, I had an on-site interview that included one design interview, which was pretty simple.

This was followed by a coding challenge, which was to implement a strategy for the Battleship board game, and an interview to go over my implementation.

Everything seemed to go really well, but I still got rejected.

This was incredibly frustrating, given that everything seemed to go seamlessly. Without an offer, it felt like a complete waste of two days.

If you want to keep a running average, and values are updated every second, how would you store the information?