const at the end of function and passing const object in a function call

#include <ostream.h>
Class B
{
  public:
         virtual void print() const
        {
                cout << "printB" << std::endl;
        }
};

class A
{
  public:
        virtual void print(const B* b) const
       {
            cout << "printA" << std::endl;
            b->print();
        }
};

main()
{
cout << "test" << std::endl;
A* a;
B* b;
a = new A();
b = new B();
a->print(b);
}

 

 

Note:

1. the const at the end of the function declaration: indicates that the "this" parameter to the function is const.

 

2. use the const because it don't modify the object.