Meta Research Scientist I interview questions

I was recommended by a Facebook employer. Before attending the on-site interview, I held one short discussion with the recruiter and one phone-interview on the technical details. The on-site interview contains four sessions, two coding, one engineering, and one research. All the interviewers are well prepared, passionate, and welcoming. The whole procedure was highly streamlined and the recruiter was extremely efficient in keeping me in the loop.

Phone interview with the HR about background and expectations on the job. Called in for on-site interview. 1 hour talk on my research topic and 5 back to back interview, lunch with a few team members. Overall experience was positive, some interviewers were more arrogant than others (a Facebook AI guy who dialed in, he was unprepared and asked me questions about my talk which didn't make much sense (probably didn't listen to my talk). One interviewer was a core developer (20 something young folk) asked me a coding question trying to make the question harder than it was. Changed the question in the mid-way which made it harder to finish. Behavioral questions followed a simple coding question (which later i found out that the question was wrongly stated).