C++ fix unused parameter warning with polymorphism

I get some compiler warnings for my program concerning unused variables, and I would like to know what is an appropriate way to fix this. I have a function that gets inherited by the base class, and in the implementation of the function for the parent I don't use all parameters that are needed for the child; of course this leads to warnings, and as I am not an experienced programmer I am not sure what is the best way to fix those warnings. So an minimal example would be: In the header: ``` class car{ public: virtual void init(int color, int size) private: int size; } class sportscar : public car{ public: virtual void init(int color, int size) private: int color; int size; } ``` In the source file: ``` void car::init(int color, int size){ this->size = size; } void sportscar::init(int color, int size){ this->color = color; this->size = size; } ```