Extremely organized and professional.

Employee referred to recruiting staff.

Recruiting member conducted a phone interview and described the process.

Passed the phone interview, leading to the on-site interview.

Recruiter explained the process and sent suggested study material (did not study enough).

Recruiter set up an optional interview training (which was completed).

Trial interview with a mentor (which was completed).

On-site interview for one full day with four individuals, each session lasting one hour, plus lunch.

As people have said, the interview questions require you to think and know your data structures cold.

Given a genealogy tree with multiple roots and intersecting nodes, write a program to determine if two arbitrary children are related.