Microsoft Software Engineer interview questions

So i had an on campus interview with Microsoft and they start the interview by telling us to write the code on white board followed by few questions about the code. after that there were few behavioral and technical questions. I got a reply from them after almost two month that I am selected for final interviews on site but there are no vacancies so to stay in touch but they haven't replied to my emails since then

Received an on campus interview after a career fair. 30 minutes 1 question written on paper. Interviewer was helpful but slightly mean. Question was not that bad but was specifically looking for the most optimal solution.