struct A {
    virtual ~A() {}
};

struct B :virtual A {};

struct C : virtual A {
    mutable int FiledC = 0;
};

struct D : B, C {
    int FieldD = 0;
};

void const_increment(const D* d) {
    D* nonConstD = const_cast<D*> (d);
    nonConstD ->FieldD +=1;
}

int main () {
    D objectD;
    const D constObjectD;
    C objectC;
    const C constObjectC;
    B objectB;
    A objectA;



    return 0;
}