Meta Developer interview questions

Got an email from Facebook that it sees my resume and wants to give me an interview. But first get a call from the recruiter to discuss about my intention. The phone lasted like 10~15 mins, just asking about my previous experience, graduation date, and my team choice. Then the 1st phone interview was scheduled. It is probably one of the hardest, thinking that they want to cut down as many people as possible. After that was the 2nd, then on-site. On-site, I met like 6 others Google Interns, and then we had a tour of the office, lunch, then 3 consecutive interviews. Then I got the offer like 3 days later (cuz I told them I had other deadlines, so they made it fast). They had a talk with one of my professor, who I wrote as the reference.