// Chapter 10 - Program 4 - VIRTUAL4.CPP #include class vehicle { int wheels; float weight; public: virtual void message(void) {cout << "Vehicle message\n";} }; class car : public vehicle { int passenger_load; public: void message(void) {cout << "Car message\n";} }; class truck : public vehicle { int passenger_load; float payload; public: int passengers(void) {return passenger_load;} }; class boat : public vehicle { int passenger_load; public: int passengers(void) {return passenger_load;} void message(void) {cout << "Boat message\n";} }; int main() { vehicle *unicycle; car *sedan; truck *semi; boat *sailboat; unicycle = new vehicle; unicycle->message(); sedan = new car; sedan->message(); semi = new truck; semi->message(); sailboat = new boat; sailboat->message(); return 0; } // Result of execution // // Vehicle message // Car message // Vehicle message // Boat message