Implementing multiple interfaces in c++

Question

I have the interface hierarchy as follows:

class A
{
public:
 void foo() = 0;
};

class B: public A
{
public:
void testB() = 0;
};

class C: public A
{
publi         


        

Answer 1

Do

class BImpl : public B {
    // code ...
}

but in B, declare the functions as virtual so the compiler will force you to implement them in BImpl