Polymorphism1

#include <iostream> 
using namespace std; 

class Vehicle 
{ 
     int wheels; 
     float weight; 
     public: 
         virtual void message(void)
        {cout << "Message from base class Vehicle \n"; } 
};

class Car : public Vehicle 
{ 
     int passenger_load; 
     public: 
         virtual void message(void)
         {cout << "Message from derived class Car \n"; } 
};

class Truck : public Vehicle 
{ 
     int passenger_load; 
     float payload; 
     public: 
          int passengers(void) {return passenger_load;}
         // NO message function
};

class Boat : public Vehicle 
{ 
     int passenger_load; 
     public: 
          int passengers(void) {return passenger_load;} 
          void message(void)
         {cout << "Message from derived class Boat \n";} 
};

int main() 
{ 
     Vehicle unicycle; 
     Car sedan; 
     Truck trailer; 
     Boat sailboat; 

     unicycle.message(); 
     sedan.message(); 
     trailer.message(); 
     sailboat.message(); 

     unicycle = sedan; 
     unicycle.message(); 
 
     return 0; 
}