13-1.cpp

为初学者提供的最佳的C++程序设计源程序库

#include<iostream.h>
class Base
{
public:
  void show()
  {
     cout<<"Parent class.\n";
  }
};
class First:public Base
{
public:
   void show()
   {
     cout<<"First Derived class.\n";
   }
};
class Second:public Base
{
public:
   void show()
   {
     cout<<"Second Derived class.\n";
   }
};
main()
{
  Base b1;
  Base *ptr;
  First f1;
  Second s1;
  ptr=&b1;
  ptr->show();
  ptr=&f1;
  ptr->show();
  ptr=&s1;
  ptr->show();
  return 0;
}