Amazon Software Developer interview questions

Everybody knows that Amazon always looks for Data Structures and Puzzles and problem solving skills. I had one online written test and one telephonic round.

Three phone interviews before I accepted a position with another company. The interviews involved answering rapid fire technical questions regarding algorithms, data structures and test strategies. During this process, I had several interviews with another large company and was offered a position, which I accepted. Questions included when would someone use an abstract or virtual class, how would you test a web page where users would input payment information, questions around object oriented programming (polymorphism, inheritance etc). The position sounded very interesting and I have friends working at Amazon who love it there. However the phone screening process was a bit drawn out and the questions asked were textbook in nature and didn't hone in on my depth of experience.