I applied through a college or university. The process took two days.

This is a campus interview. The first round consisted of three programs on trees and graphs, and it was not that easy. Then, immediately, we had a normal talk on projects we had done. Next, we were given projects and asked to submit them by the next morning. We hardly got twelve hours, after which we were asked to give a demo presentation on our projects. After this, we had a telephonic discussion, and we were given a six-month internship. They said that, based on performance, it would be converted to full-time FTE.

Find the number of levels in the tree given the first line is the number of cases, and the second line is a list of numbers in an array where the index was the value and the value was a parent.