Google Developer interview questions

After an interview workshop run by Google at my university I was contacted a few weeks later by a Google Recruiter. I initially had a 45 minutes phone interview with an engineer answering questions and writing code on a shared Google Doc. After that I was invited for on-site interviews. In total there were 5 interviews of 45 minutes each on that day. 4 of the interviews were mainly about problem solving and coding. The other one was more about system design (no coding, it was just a discussion). All interviews were with engineers. After the on-site interviews they asked for references from supervisors/managers etc.