Microsoft Intern interview questions

Got an interview opportunity from career fair on campus and the interview was also held on campus. There were two questions. Both were pretty straightforward and the interviewer was very patient in explaining all the questions I had. My first code missed out a lot of corner cases. The interviewer was nice enough to point those out for me. I was able to correct them afterwards but still no luck for the next round.

there was a aptitude round consisting of 15 questions on c/c++. second round was a coding round where 2 coding questions were asked. 3rd round was a telephonic round where he asked me general question about me and the projects that i had done then he asked me 3 algorithm