You have to store pointers to your abstract type. Otherwise it's going to try to instantiate instances of that class, which it can't since it's abstract.
You have to store pointers (or better smart pointers like std::shared_ptr or QSharedPointer) in your hash container.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.