Amazon Developer interview questions

I'm a master's student in computer science and my advisor approached me about a possible opportunity with Amazon. One of her former students now works for the company and had told her they were looking for software developers. I submitted my resume via email and was scheduled for a phone interview within the week. A few hours before the interview I received an email stating they needed to postpone it until the next week. I finally received the call after 7 days of waiting and proceeded with the phone screening. The interview was being conducted by one of their developers, so the expectation of technical knowledge was high. He was courteous and friendly but immediately got down to business with the first questions. The interview consisted of a few short-answer questions and several more open-ended problems dealing with algorithms and software design. The questions were fair and not overly difficult, and the interviewer offered a few hints and nudges in the right direction when I got stuck on something. I've heard from others that there is something of an "Amazon culture" of cockiness and a general attitude of being the best at what they do (which certainly may be well deserved judging by the size and success of the company). I did get something of a sense of this when I was asking my questions at the end of the interview--when I asked the developer what his favorite part about working at Amazon was, he immediately replied that it was the confidence that he could solve virtually any problem posed to him, no matter how large. Again, he was polite and helpful through the entire call, but he wasn't much for smalltalk or joking around. From word of mouth and my conversation with this developer it seems like a pretty serious work environment.