Rubrik Interview Experience - G6 (CPD team)

Round 1: OA

10 MCQs (Multithreading, OS)
1 DSA (DP, medium level – similar to minimum cost to split array)

Round 2: System Coding

Quick intro followed by problem on HackerRank
problem statement was something like this : Design a backup system with dependency graph (each backup has end time + retention)

APIs to implement:
add_dependency
find_recovery_chain
expire_backups

Asked to first solve in single-threaded, then make it thread-safe
Completed single-threaded solution, ran out of time for thread-safe part
Interviewer was helpful and guided well

Result : weak yes, HR mentioned she will check with HM weather to proceed or not -- still waiting.

Big opportunity loss!

Edit 1 : saw a opening again so reachedout to recruiter and next round got schedule.

R3 - debugging round

got 1 big code of standard barber probem with so many shared resources like chair, tools (brush, scissor, comb) and needed to fix all the bugs.

was able to find 3-4 bug and there was at least 1 more bug as my test case was failing for 1 case. [we just tested on one test case only we were checking the execution and everything was good but to shutdown once everything is done was not happening as there was somewhere deadlock, 21 customer came and 18 got process but 3 got stuck and code was giving TLE]

guessing
1 : weak yes - as i explained all the code and did suggested couple of enhancement, some suggestion wasn't fully right but the discussion went well.
2 : no - as at least 1 edge case wasn't working

may be two weak yes wasn't good enough to proceed.

verdict : Rejected

overall interviewer was good, but didn't had much experience with multithreading code and was immense under pressure as soon as i saw the code it was some 170-180 line and lot of shared resources.

do practice for this kind of interview as well.