1 coding challenge: leetcode easy/medium 2 phone screens: CS fundamentals, programming language-specific knowledge, and leetcode medium onsite: NDA but a huge focus on low-level and systems knowledge (systems questions were by far the hardest of all the quant places I interviewed at)

2 rounds. 1st round is about C++ OS knowledge and 2nd round is coding. 1st round is nice but the experience of the second round is very bad. The coding problem is easy but it seems that interviewers have different ideas about the solution. This problem can be solved easily if the interviewer tells me that he doesn't agree and we discuss what we think about it. However, the interviewer only says "good, it's fine, I understand" but he actually doesn't think so. He also explains nothing about the problem. No useful information and fake feedbacks make it hard for me to figure out the problem and I never know what he really wants to know. Finally, he finish the interview in 30 minutes, which is 30 minutes ahead of the scheduled slots. This makes me feel insulted. I think the interviewer only wants someone who can know what he thinks with the superpower. Really bad experience, never want to interview with him again.