X Developer interview questions

Submitted the resume through twitter careers website. HR got in touch to schedule a 45 minute interview. Was asked to write code on collabedit. The question was to find the subtree with maximum number of files given a filesystem tree. The interviewer clarified that directories need not be counted as a file. The interviewer also gave system call APIs (that he had made up) that should be used to access the filesystem. I provided him a recursive solution coded in C++.

I was referred by a friend. The recruiter contacted me shortly, asked why Twitter, what I would like to work on and if I had any time constraints. I was shortly scheduled 2 phone interviews consisting both on talking about my projects and interests and also CS problems, writing code online. Both interviews allowed time for any questions and short discussions afterwards. Then I had 6 on-site interviews with back-end people (that's what I opted for). They mostly consisted of whiteboard coding and some let me write on the computer. Some were CS questions some architectural and backend. I recommend preparing for it, read about algorithms and be confortable writing code both online (though just a text editor - no feedback) and on a whiteboard. Depending on what you are applying for be prepared for architectural / design questions too. Overall everybody was really nice and have a very positive perception. I got to ask about some of their challenges and discuss their solutions.