Amazon Software Development Test Engineer interview questions

I applied through a staffing agency for SDET I position, Telephonic interview was conducted. As I was not aware of Amazon process much I couldn't prepare well. I got call from SDET II on scheduled time. She started asking about my current project, role in my project and difficulties I faced in that project.Then she gave me string problem, I had to write a method which should return count of numbers. EX: Input "AABC32DE4P%@23Pu" output should be 32+4+23 = 59 I explained an algorithm to solve this, She asked me to it, I coded in Java. I took little extra time to fine tune it. Then she asked me to write some test cases to test the above function, I gave around 10 test cases. After this round I got mail saying I got rejected. I felt lack of preparation and awareness about interview process reasons for rejection.

Telephonic followed by technical interview at Bangalore office.Worst interview of my life .Please boycott this esp in India.They didn't even ask for food after taking 2 hours of interview they said that 2nd round would be conducted 1 or 2 additional rounds will be there and after waiting for 1 hour the HR told to me you may leave for the day.