Amazon Software Development Engineer interview questions

Contacted by a recruiter through LinkedIn. After initial screening, they invited me to attend interview onsite. Very friendly interviewers and I had lot of fun during the interviews. Interview consisted of 3 regular 1:1 interview + 1 bar raiser interview - each about 45 mins and about 10 mins for the candidates to ask any questions. 1. Very simple data structure question 2. How do you design type question. Lots of what if this happens and what are the assumptions type question. 3. Bar raiser interview: Another design type of question with lots of open ends. 4. Another design related question with respect to 3G technology.