I met some engineers from Palantir at the UIUC career fair. They asked me some algorithm questions on-site. After a few weeks, I received an email asking to set up a phone interview. Two weeks later, I had another round of phone interviews. Both phone interviews were very similar. I assume I had two rounds because I was living outside of California. After I passed the phone interviews, they flew me in for an on-site interview. They offered me two nights in Palo Alto, and the trip took me three days. The hotel was very nice and cozy. They essentially paid for everything I spent at the hotel. The on-site consisted of four one-on-one interviews and a product demo. All the interviews were technical. They were much harder than the phone interviews. I really liked the atmosphere of Palantir and the surroundings. Such a pity I didn't get an offer.

Generate a Fibonacci sequence: each number is the sum of the three previous numbers.

Do a postorder binary tree traversal with constant memory (no stacks).

Given an array of n unsorted integers, and each number is at most k positions away from its final sorted position, give an efficient sorting algorithm.