First, I got an interview on campus, then scheduled an on-site test in Seattle one week later.

The first interview on campus was extremely easy, with questions like "Why do you want this position?" and "Write a program to reverse a string."

The on-site interview was scheduled for 2-3 days. They gathered all the interviewers together for a dinner to discuss the interview process and life in Seattle.

The interview took all day, with 4 one-on-one interviews. Each interview was with a different person and lasted for 30 minutes. The questions included data structures, algorithms, logic, and simulation.

They decided to give the results right after the interviews, which made people very excited. However, I did not get the offer.

There is an array with a length of 99. Each spot will have a number from 1-100. Numbers will never repeat in the array. Give as many ways as possible to find the missing number.