Citadel

Had a one-hour phone screen set up by a recruiter. It was conducted by an engineer pulled in at the last moment because the original interviewer skipped due to a prod issue. This is a bad sign.

First round interview. Interviewer was friendly. The interview mostly focused on financial domain questions, data structures, bits and bytes, multithreading, and general C++ language fundamentals. No algorithm questions were asked. The interview

First time talking to the manager (or the team leader). A simple question: A number from 1..N is missing, and another number from 1..N is duplicated. Find the missing number. Provide as many solutions as possible.