Jane Street Trading Desk Operations interview questions

2 round online interviews. first round is leetcode, 2nd round is online 1to1 zoom interview, asked me brain teaser questions only, did not discuss cv. i f up on quite easy questions. shame on me.

First was a excel take-home task. Tedious and detail oriented. Took quite a while to be sure I had got it right - standard excel operations and looking at financial data (haircuts, different types of options). Then was brainteasers. First was a water content (classic one with 99% to 98% volume, what is change of weight), then a simple number theory question, where you had to spot a trick, then an adaption of the secretary problem with just 3 candidates - had to calculate expectation, then a slightly awkward speed, distance, time question. Next round was coding. You weren't allowed to run any code, which sometimes made debugging difficult. First question was return 3 largest numbers in a list (don't just do it naively, you want constant time), then adaptation of this, returning n largest numbers. My code was slightly buggy, as I didn't really practise whiteboard coding. I failed after this - next step was onsite. I decided to do a GDPR request, and it turns out the main reason I failed was for not being friendly enough - definitely a new one for me. I felt like I was matching the interviewer, but clearly you need to make more of an effort.