After submitting my application, I was emailed a link to an online coding challenge that ran for approximately 75 minutes.

This contained a single problem centered around checking for fraudulent bank accounts. After completing this (passing 8 out of 10 unit tests), I had two one-hour Skype interviews with different engineers.

In these interviews, I was asked several questions and given a coding challenge. Looking back, the challenges were not too difficult.

One tested if I could find an optimal solution, while another tested my ability to structure code. Unfortunately, I didn't arrive at the desired solution either time and did not make it to the next round.

Why would you be a good fit for Palantir.

Given a set of number ranges, e.g., [3,6], [5,9], [1,2], [10,15].

Develop an efficient algorithm to output the smallest number of ranges without losing any information. For example, output [1,2], [3,9], [10,15]. Here, [3,6] and [5,9] overlap, so they can be merged into a single range [3,9].

Extra info: If you had [2,5], [6,7], these would not merge, as [2,7] would include all numbers between 5 and 6, which were not in the original subsets.

You should be able to come up with a solution better than O(N^2).