I had an initial call with a recruiter, and then proceeded to the phone screen. The question was of an lc medium level. The interviewer was pleasant and helpful. He did say we would build up on the question. We talked about a potential solution and worked towards it. The code I wrote ran, with some errors so we worked on fixing them. I felt like I did a pretty good job of it. However, we never reached the point of building up from the initial question, and consequently I did not make it to the next round. I would be interested to know what the criteria of selection is. Nevertheless, it was good practice for other interviews.