class C {
 public:
C();
virtual ~C();

C(int x)
{
    y = x;
}
void print()
{
    cout << y << endl;
}

private:
int y;
};

class B : public virtual C {
public:
B();
virtual ~B();
B(int x)
    : C(x)
{
}
};

class A : public virtual C {
public:
A();
virtual ~A();

A(int y)
    : C(y)
{
}
};

class D : public B, public A {
public:
D();
virtual ~D();

D(int x)
    : B(x)
    , A(x)
{
}
};

C* a = new D(3);

a->print();