class Base i class Derive public Base public: public virtual int Set(int a, int b) int Set(int X, int y) }; nt Set(int int)是處画数}; class Base class Derive: public Baset publIC public virtual int Set(int a, int b) int Set(int x, int y=O) 两个Se0函数参数 不一致,是重载, 不是虚函数29 class Base { public : virtual int Set(int a, int b) { ..... } .... }; class Derive:public Base{ public : int Set(int x, int y) { ..... } ..... }; class Base { public : virtual int Set(int a, int b) { ..... } .... }; class Derive:public Base{ public : int Set(int x, int y=0) { ..... } ..... }; int Set(int ,int )是虚函数 两个Set()函数参数 不一致，是重载， 不是虚函数