At first, it was a fairly easy phone screening. They asked me to sort a list of tickets according to their visiting order; a hash map would do this. Then, after two weeks, I was asked to select an onsite date.

During the onsite interview, the first round consisted of a list of algorithm and data structure questions with two interviewers (I forget the specific questions, but they were of average difficulty).

The second round was mainly about databases, I believe. I messed up that round because the interviewer did not ask questions directly but was trying to confuse me all the time. Yes, he was doing that on purpose. For example, he claimed that 2.25 and 2.250 are encoded differently as doubles, which made me think he was insane or had learned computer science from another world.

So, when he asked me to change the database structure according to a query, I did not recognize the trick. You should use indices to speed up a query, not change the database. I was walked out after that round.

How would you know if a double has four decimal places?

Design a database for a car rental system.

How do you know there exist two numbers in a given array which add up to a certain number? (given: array, target sum, return: true or false)