Meta Software Developer interview questions

I was contacted by a recruiter via telephone. The phone conversation was simple enough to warrant a trip to the office. The office was nice- catered food, and unlimited soda and candies. The first round interview lasts about 1 hour and consists of questions (no surprise) asking about time complexities calculation and data structures. Make sure you at LEAST know tree traversals before you go into the interview. Given the short time limit, feel free to ask your interviewer for help to speed up your answering.