A Google recruiter contacted me after I applied online. I had one coding phone interview from the Google Mountain View, CA office. The interviewer asked me a thesis-related question since this was a Machine Learning-related job, followed by a coding question. After four days, the interviewer pinged me with a positive response and asked me for an on-site interview.

I was interviewed at one of the Google Germany offices.

Onsite experience: Standard Google interview. Five coding/design interviews, one lunch interview.

Standard algorithms and data structures questions.

• Two pure coding/algorithms questions.
• Two game-solving questions. In one of them, after coming up with the solution, the interviewer also asked me to design how I would represent the game and then code the solution. I could hardly code 30-40% of the solution.
• One system design question where they asked me to design one of the Google search features.

Lunch interview: Hated it! After lunch, I wanted some time to be on my own, just to gather up some energy after three exhausting interviews. I thought the interviewer would leave me alone after lunch, but he was sitting in front of me, staring at me and waiting for my next question to answer. The only question I had was, "When will you leave me alone?!"

Overall positive experience. One thing that was different from all the other interviews I had in the past was that the interviewers weren't helping at any point. Whenever I was struggling, they were just sitting idly, waiting for me to solve the question myself. Except that stupid game design/solve question, I was able to come up with the solution and then code it within 45 minutes.

You are given a linked list where each node contains one extra pointer. This extra pointer points to any random node in the list. Create a copy of this list.