class B
{
private:
    int m_data;
public:
    B(int data=1)
    {        
        m_data=data;
    }
    int doGetData()
    {
        return m_data;
    }    
    ~B()
    {
    }
    void test()
    {
        Speaker();
    }
    virtual void Speaker()
    {
        cout<<"B is speaking!"<<endl;
    }
};
class C:public B
{
protected:
    int m_data;
public:
    C(int data=2)
    {
        m_data=data;
    }
    
    ~C()
    {
    }
    void Speaker()
    {
        cout<<"C is speaking!"<<endl;
    }
};
int main()
{
    C c(10);    
    c.B::Speaker();
//c.B::test();
    return 0;
}