Meta Software Development Engineer interview questions

I have a contact in FB. Applied and they asked some basic interview questions with phone and codepad.io. Didn't do well altgough got the first 2 questions right since I'm too slow. Questions are very basic.

I got two phone screens. Then Facebook flew me in from Europe for onsite interviews: 1 design interview, 1 "culture fit" interview, and 4 coding/datastructures. I did well to pretty much of all them except one coding. After about two weeks, the recruiter contacted me to tell me that they weren't able to take a decision, so I got an extra phone interview with a "very senior" guy a few days afterwards. It was an enjoyable experience for most of it. The most important problem was one interviewer who was obviously not ready to give interviews: he was totally unable to explain the problem I was supposed to solve and was interrupting me every minute.