normal functions accessed from pointer : object pointer « Class « C++ Tutorial

1. C++ Tutorial
2. Class
3. object pointer

#include <iostream>  
  using namespace std;  

  class Base{  
     public:  
        void show(){ cout << "Base\n"; }  
  };  
  class Derv1 : public Base{  
     public:  
        void show(){ cout << "Derv1\n"; }  
  };  
  class Derv2 : public Base{  
     public:  
        void show(){ cout << "Derv2\n"; }  
    };  
  int main(){  
     Derv1 dv1;           
     Derv2 dv2;           
     Base* ptr;           
    
     ptr = &dv1;          
     ptr->show();         
    
     ptr = &dv2;          
     ptr->show();         
     return 0;  
  }