NVIDIA interview questions

I was asked a question on CUDA and was asked to implement the solution in CUDA. It was challenging as interviewer asked how to optimize it based on GPU arch.

I applied through LinkedIn and a recruiter reached out to schedule a call with the HM. It went quite well and I was then proceeded to the next steps. I reached out to the recruiter asking what I should expect from the interviews, was it a coding interview, technical interview etc. I expected to at least be informed about what was next. Unfortunately I got no responses from the recruiter at all. Then came the interviews. It was funny that there were no greeting/introduction whatsoever, I was just bombarded with lots of technical questions on a wide variety of topics related to the role. Then I was told, it was done and if I had any questions. So I find this quite strange - maybe the interviewers weren't properly trained? I reached out to the recruiter after the interviews about the outcomes and the updates but I didn't hear back. Throughout the whole process, I had never talked to the recruiter at all and I wasn't told what to expect, how many rounds to pass etc. I think as a candidate I deserve to know this information so I know how far I am in the process.