The first round was the best interview experience I've ever had, and the interviewer was the best I've ever met. At first I encountered some connection issue and the video conference was interrupted. When I dialed in again, he comforted me that's alright. During the coding test, he first gave me an overview of the problem I need to solve, then he asked me not to rush into coding, but told him the idea first. When I got stuck with some compile errors, he asked me if I understand the error message; when I said I don't remember an API call he said I could Google as long as I shared with him my findings. My solution didn't match entirely with the expected output, he asked me to take a step back and make sure each small parts work as expected to narrow down the scope of the problem. Even though I didn't find the bug eventually, he said he like the solution and told me not to worry too much about it because we were almost there. When I got the chance to ask him some something in the end, he got the point of my questions accurately and shared with me his experience very genuinely.
The second round was the worst interview experience I've ever had. First the connection was bad. The video was constantly freezing, and I'm pretty sure it was not my network problem this time, because it was the interviewer who left the conference and then rejoined. The first interviewer was in a meeting room but looks like the second interviewer was in front of his own desk. What make things worse was he was wearing a pair of headphone that doesn't seem to have a microphone. Judging from the voice quality he was very likely using a built in microphone from his computer. I could barely hear a complete sentence during the entire interview. The interviewer was not much of a talker as the first one, and after I asked him to repeat a few time, I could sense a bit of impatience. So I was a bit scared to tell him that I cannot hear him clearly and asked him to get a better setup. I figured it wouldn't really help, because when he threw me the question directly and explained a little bit, but didn't ask me what my idea was and how I was going to approach. It all seemed to me this long overdue interview was something fell on his head and he didn't care at all. I decided to get into the question and not let these things interfere.
As for the coding session, the problem itself is not that difficult, as it was similar to the first round. Usually there'll be some problem description and starter code (as it was what I got in first round and I believe in most online coding practice platform). It seems to me either he forgot to bring them up or did it on purpose. There was only a main() function and inside it an object calling a member function. The interviewer only told me what the problem was, but as I couldn't hear him clearly, I would really hope there's a description. He didn't tell me what should be implemented so I asked him, mainly wanted to clarify if my understanding is correct. But he just laughed and said that's what the test is all about.
I coded it up more fluently than the first time as I believe the problem can be solved similarly. Again the output of my solution was slightly different than the expected, so I started to debug. The interviewer neither comment on my solution nor offer any help up to this point. I doubt if he cared to understand what I was trying to do. Quite often I had to speak out why I did what I did and hope that he would listened. After spending quite sometime but didn't get the problem solved, he finally suggest that if I use pen and paper to do a walk through then I'll be able to spot the little bug. I would think that is a good suggestion, but the current situation is I've already narrow down the problem to these few lines of code, there's no point of doing the whole walk through and no time. Anyway, I didn't argue with him and took his advice, but just ended up at the same spot I was at before. I tried to discuss with him what I think of those few lines of code, and why they might be problematic. But he reassured me that they're behaving as expected. Then he finally started to look into the problem together with me. He changed a little bit of the code, but that seems to me just a different style of writing, it didn't get to the heart of the problem. I took my courage to say let's just try not to be smart and write these few lines in a stupid way, and we finally both found the actual problem. Unlike the first interviewer who would ask me to evaluate my solution and ask if I have alternatives, this interviewer didn't ask me anything after the problem was solved, nor comment on the solution and the problem we just encountered.
I didn't pass the second round of interview. My conclusion is: I feel very unlucky because I missed the chance to work with the first interviewer; and I feel relieved that I don't need to work with the second interviewer.