Why would the conversion between derived* to base* fails with private inheritance?

Question

Here is my code -

#include
using namespace std;

class base
{
public:
    void sid()
    {
    }  
};

class derived : private base
{
public:         


        

Answer 1

Try this:

#include
#include
using namespace std;

class base
{
      private:
      public:
          virtual void sid() // You might want to declare sid virtual
             {
                  cout<<"base";
             } 
          virtual ~base() // You then probably need a virtual destructor as well.
             {
             } 
};

class derived : public base //public inheritance
{
      private:
      public:
             void sid()
             {
                  cout<<"derived";
             }
};

int main()
{
    base * ptr;
    ptr = new derived;
    ptr->sid();
    getch();
    return 0;
}