My first interview was pretty straightforward. I had to implement map, fold, and filter, as well as create a function called memo to memoize a given function.

The day after, I was scheduled for another interview at the end of the week.

This one was tougher but still manageable. The problem was to implement a purely functional heap, ensuring two invariants held.

My third interview required me to implement a function that, given a grammar and a max depth, calculates the longest word generable. I didn't pass the last one.

The last one was tougher. The only thing I regret is that after being rejected, I asked for clarification but received no response.