Google Software Engineer(Internship) interview questions

Difficult questions, had 2 rounds. First round was OA, second round was with hiring manager. Got rejected after hiring manager round. Everyone was nice and friendly. Was referred in, from what I have heard you should have a referral as it is difficult with a cold application.

quick call with a recruiter followed up with phone screen with a manager. No response for following couple days and then got another interview with another manager level person. Then, I got an email from the recruiter saying I would get an offer very soon.