Amazon Software Development Engineer interview questions

I was contacted by a recruiter about different positions and opportunities at the company. Afterwards they scheduled some initial phone screens. If all goes well you are invited for an on site interview.

First we waited. Then we were brought to take some pizzas and talk with the interviewers. Then we took four back-to-back interviews. Some design and algorithm questions. I remember there is a leetcode problem that computing how many ways from upper left corner to bottom right corner with some obstacles in a matrix. I was also asked about some behavior questions. After the interview is done, the last interviewer brought me to go out. About one week later, I got the email that I still need to move on.