Came to our career fair. Interviewed people there, shortlisted them, and sent invitations for the on-site process.

On-campus interview questions:

• Find the middle of a linked list.
• Find all the paths in a binary tree that sum up to a given value.
• Write test cases for Bing (yes, really!).

On-site interviews:

• Interview 1: After discussing past projects, write test cases for a routine that takes two Cartesian coordinates as input and draws a line joining them. The display pane can show points only where x and y are between -100 and 100. How would you design this for a blind person? Choose the best six test cases and explain why.

• Interview 2: After discussing my resume, write code to find all palindromes in a string. Code both naive and efficient approaches. What if the string had spaces, like "race car," which is also a palindrome? What if characters similar to an alphabet from other languages were considered the same character? What if you were implementing a web service with a page that takes an input string in a textbox and displays all palindromes? What test cases would you write to ensure the service works correctly? What if your service was being used only by people in Germany? How can you optimize?

• Interview 3: After resume discussion, talks for five minutes about his team (MS Office SharePoint). Just one question for the entire interview: Given an API with a string argument and an int return type, what could it be doing? Imagine the different possibilities and how you would decide on test cases based on the functionality of the API you thought of. Consider tests that assure sanity, positive examples, negative examples, security, and scalability of the API.

• Interview 4: Discusses my resume, talks about his team and briefly about his 20 years of experience at Microsoft (at which I instantly remarked, "I would have never been able to pull that off!"). Says, "I see from your feedback that you are more of a problem solver, so I would like to test your imagination." Asks me to implement the string.Split(some char) API of C#. Write test cases that would fail my code. Write code to fix those failures, iterating until all are resolved. At the end, tries to sell me the SDET position, saying it's lots of fun and that SDE/SDET switching happens every couple of years.

Otherwise, Microsoft pampers its on-site invitees. They pick you up from the hotel and airport in a limo, offer $75 per day for meals, provide crazy discounts in the Microsoft store, and offer free taxi/rental car to explore the city with $50 reimbursable, apart from meals and taxis, if you want to buy other items.