I was applying from a recruitment agency and had a trivial phone screening and a 1:1 interview just to check if I met a minimal level of competence.

Then the interview at the company was with a bunch of interested line managers. They asked general IT questions like "What is unit testing, module testing? What design patterns do you know?", as well as specific C++ questions: "What is polymorphism? What is virtual inheritance?".

Then I had to write small code like Fibonacci numbers or a simple shell script. They responded a few days after the interview.

Virtual inheritance in C++, because it is very rarely used.