I applied online through the Facebook website and heard back from HR within two weeks.

After speaking with the recruiter, we set up a phone interview with one of the engineers. The phone interview was about 20 minutes long and consisted of two questions which were algorithmic in nature, one of which was reversing a linked list.

I heard back from them about a week later, and we set up a time for an on-site interview. I was allotted $1000 USD for travel expenses to travel from Toronto, ON to Palo Alto, CA.

The on-site interview lasted four hours and was split up into one-hour interviews with a different engineer. The questions were mostly abstract and language-independent. The content of the questions varied from riddles to database design.

My impression of the first three engineers was good; they seemed like nice guys and knowledgeable. The last interviewer came off as pretentious; I felt as though he wanted me to fail – just my opinion!

Overall, the office culture seemed relaxed, and the problems they are solving there are interesting. I'd recommend interviewing with them if only for the chance to visit Palo Alto!

You have two lightbulbs and a 100-storey building.

You want to find the floor at which the bulbs will break when dropped.

Find the floor using the least number of drops.