I was contacted by a recruiter through my LinkedIn profile. The recruiter had a particular team in mind for me. It turned out I knew some people who already worked there, and they highly recommended me, so I was able to bypass a phone screen.

I was told I would have to do all of my interviews in either C, C++, or Java. I didn't know any of these languages particularly well (my professional experience has been more in dynamic scripting languages), so I told the recruiter I would need some time to review Java. I managed to drag it out for a number of weeks, but ultimately did not come in adequately prepared for Java coding exercises.

The interview consisted of four or five back-to-back, one-hour, one-on-one sessions with engineers asking challenging algorithm questions. One session seemed more focused on system design.

Several things were very challenging about this interview:

• It had a sustained level of intensity over a long period. By the time I hit hour three or so, I was mentally drained.
• I was trying to use a language I didn't know well.
• The algorithm questions are obviously designed to be challenging, and your time is very limited.

I did come away feeling like Google would be a great place to be an engineer. The interviewers seemed to want me to succeed for the most part.

Write some code to parse a particular grammar. The grammar was ambiguous, so you would have to be able to discuss how your code impacted the way that statements in the language would be interpreted.