I went through 3 rounds of interviews, two technical with software engineers, one with HR, then the last with the head of R&D himself. I answered all the technical questions efficiently, so I don't think my lack of an offer was due to that. As other interviews post on here, be wary of the "why Bloomberg" question; I'm guessing my answer to that was the reason I was rejected. It's a little hard to not be a bit miffed about it since all signs were going very well, just to get a rejection without a real clue as to why.

15 minutes talking about resume, 45 minutes for 2 medium leetcode style coding questions (using code share), the interviewer was very friendly and communication is even more important than passing all test cases.