C++ Programming - Functions - Discussion

#include<iostream.h> 
class BaseCounter
{
    protected:
    long int count;

    public:
    void CountIt(int x, int y = 10, int z = 20)
    {
        count = 0;
        cout<< x << " " << y << " " << z << endl;
    } 
    BaseCounter()
    {
        count = 0;
    }
    BaseCounter(int x)
    {
        count = x ;
    } 
}; 
class DerivedCounter: public BaseCounter
{
    public:
    DerivedCounter()
    { }
    DerivedCounter(int x): BaseCounter(x) 
    { }
};
int main()
{
    DerivedCounter objDC(30); 
    objDC.CountIt(40, 50); 
    return 0; 
}