Meta Software Developer Internship interview questions

It was a 45-min phone technical interview. It started with the regular behavioral questions like "tell me about yourself" and "why FB." The coding question was to determine whether a BST is valid.

HR was bad. But Interviewer was kind. HR kept messing up in emails, such as giving me wrong scheduling links, coderpad links, etc. However, if a friend refers you for the job, it really does take like 2 days for them to tell you to schedule an interview.