Google Software Engineer Intern interview questions

It was a google hangout interview where I coded in a googledoc in front of an engineer. It was suppose to be a phone interview, which instead became a google hangout call. The process was standard with behavior questions, then a coding question, then questions for the interviewer. The person was nice and very understanding. They asked me to calculate the run time of my algorithm.

I submit the resume online, after three weeks the HR arranges me two 45 mins interviews. The first asks about how to compute the product of an array except the entry at each position, and how to judge whether a string A is a variation of string B. The second interviewer asked my research interests and a brain teaser question.