Amazon Software Engineer internship interview questions

Besides the normal interview questions, such as tell me about yourself or tell me about a time where you could've done more to work as a team, there were also technical programming questions. 2 on a pre-screening exam and 1 during the interview, all three were very tough. Even though I only passed half the test cases on the pre-screening test, I was still offered an interview, but I couldn't solve the problem during it at all and wasn't offered a job afterwards.