Uber Software Engineer interview questions

Contacted by recruiter through LinkedIn. The interview process was standard like talking with the recruiter about background and interests, and technical phone interview. The process was smooth and promptly. The technical phone interview on string search problem which required recursion to get the correct result. I got stuck in the middle, the interviewer gave me pointer by asking different questions on my approach but couldn't finish in 45 minute time interval.

Take-home challenge -- create a sudoku app. Rejected outright with no context. Was a good working app which took a solid couple of days of development. There were no guidelines given.