FireEye Senior Developer interview questions

1st round online Hackkerrank coding, Second face-to-face technical, 3rd managerial. Did attend the 2nd round which was very good, as I did explain all the design questions and wrote the PGM correctly and was expecting positive feedback but didn't receive any reply from HR even after putting mails twice. Very unprofessional and the interviewer was very confused or more like not interested in taking the interview as he was getting blackout and taking breaks in the just 1hr interview session.

There were 3 rounds of technical interviews followed by an HR round. All the interviews were remotely done (COVID closures). First round (technical round, 1 hour) was taken focusing on language specific questions and was asked to do some coding. Second round (technical round, 1 hour) was taken professionally focusing on OOPs, data structures, algorithms and problem solving. In depth Python questions were asked too. Third round (managerial round, 2 hours) was taken by hiring manager who was COMPLETELY IMPOLITE , UNPROFESSIONAL, RUDE. The round was 85% technical and 15% managerial. Was asked a couple of algorithms, understanding a piece of code etc. Fourth round (HR round, 30 minutes): HR related questions and salary discussions. I declined the offer because of the unprofessionalism displayed by the rude manager.