There were a total of 4 rounds. Each round had one or two interviewers. The range of possible questions is very wide. The interview starts from 8:30 am until 3:00 pm. If C++ is your preferred language you should definitely learn something about STL.

1. shortest palindrome - https://zigin.co/interview/detail/1623.page
2. given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array. For example, Given nums = [0, 1, 3] return 2
3. question about matrix
4. there is a building of 100 floors. If an egg drops from the Nth floor or above, it will break. If it's dropped from any floor below, it will not break. You're given two eggs. Find N, while minimizing the number of drops for the worst case