C++程序设计教程：17_1

class A{
public:
int GetpA(){ return pA; }
void SetpA(int a){ pA=a; }
private:
int pA;
};
class B,public A{
public:
void OnB(){}
};
class C,virtual public A,virtual public B{
public:
Sc(){ /*use GetpA() and SetpA()..,*/ }
};