Yandex Software Engineer interview questions

A Yandex recruiter contacted me several months ago about a two positions of Software Engineer for customer-facing product and as a Systems Programmer for internal systems. I decided to try. The process took less than a month. After resume checks, recruiter offered to go through Skype interview. Interviewer were very friendly, but despite I was preparing for coding interview, most of the questions was about Linux ("classic" questions on how to find CPU consumer or get rid of zombies/uninterruptible tasks). Less than in a week they invited me to on-site interview (and paid for one-day travel to Moscow). It included 4 hour interviews for Systems Programmer position +1 bonus interview from another product team and one hour dedicated for dinner with recruiter. First three hours were devoted to coding -- you'll be expected to implement a simple algorithm or C++ utility class like very special type of iterator. I utterly failed third one, but interviewer was very helpful and finally got the seemingly right code from me (even though with 15-minute overtime). Following two interviews very much easier: a little bit of code fixing and coding, large system design (again, no very specific or hard problems here) and lockless structures.