Siemens Senior Software Developer interview questions

First round was easy. Interviewer was knowledgeable and was asking questions from basic OOPs concepts and current project architecture. Cleared first round but couldn't clear next one. Second round was taken by one guy and one lady. The lady asked some basic questions from a sheet. She didn't seem to understand the answers. She was just checking if it matched the answers she had. The other guy had a lot of attitude and was asking weird questions. Like how did Microsoft implement List collection class. Write the code for this(!). His english was very bad (kept saying "actually" in every sentence). He was not able to express properly the question he wanted to ask and seemed irritated when I tried to clarify the question. Overall the interview process was fine. Expected better interviewers in second round.

It was descent and good interview . Took one day. But took one whole day and till now they did not release any Offer letter. If they are not interested they should reject us.