Amazon Software Development Engineer interview questions

First they set up a technical phone interview with me, but the interviewer was out of town without informing me. After a large amount of email, he finally replied to me for a reschedule after a week of no communication. During the interview, the interviewer do a sanity check then follow up with 2 technical questions, 1 for actual concept and 1 for logic design.

Two Online assessment rounds followed by 30 min video interview. First round contains three sections debugging, aptitude and one coding question. Second round contains Simulations and two coding questions out of which the second question was very tough. Overall interview process was challenging. The second round was lengthy. For some people third round was onsite and for some people it is 30 min video interview where they discuss the that we write in the second round.