Meta Software Engineer interview questions

Contacted by a recruiter who did a poor job screening me for the position. I'm a front end guy and they were hiring for a PHP backend. I went through the process for the experience, and it was incredibly tough. I failed miserably on the CoderPad interview, but it was still a good experience. I say it was good because they were very respectful and communicative. They send you a bunch of tips for preparing for the technical interview. I just bombed :)