The whole process, from applying online to getting the results of my interview, took four weeks.

After applying online, I was contacted about doing a phone interview a few days later. The phone interview was with a team lead who was pleasant. They asked me a little about myself, a straightforward programming question, and then described the team.

After I got the thumbs up from the phone interview, Microsoft made arrangements for me to fly up and stay in a hotel for two nights to do an on-site interview a week and a half later. The on-site interview was for four and a half hours with four interviews, each with a different senior developer or team lead.

All four asked a coding question, which weren't exceptionally difficult but were challenging enough. As I talked through the problems, they helped me along the way, which made me uneasy about how well I was doing. This made it worse.

After a week, I received word that they were going to decline an offer and that I could apply again in six months.

Write a function that takes an array of signed integers and a target integer. The function should return true if any two integers in the array add up to the target integer.

If it didn't exist in .NET, how would you implement the dictionary class?