I had a phone call where I was asked basic questions about myself and had to send in my grades.

I then had two technical interviews back-to-back, each lasting 40 minutes. In both, I had to write code after answering questions.

The second interview included a question on a whiteboard.

Situation: Given a file where each line contains a date of birth and a date of death (dates are from 1900-2000), return the number of people alive at a given year within this range. You can assume that a person was born on January 1st and died on December 31st. Suggest a data structure for this as well.