C++ Car

car.cpp

#include <iostream>
using namespace std;

class Engine
{
public:
  Engine(){
    cout << "Engine constructor" << endl;
  }

  void run()
  {
    cout << "I'm running ..." << endl;
  }
};

class Wheels
{
public:
  Wheels(){
    cout << "Wheel constructor" << endl;
  }
  void spin()
  {
    cout << "I'm spinning ... " << endl;
  }
};


class Doors
{
public:
  Doors(){
    cout << "Doors constructor" << endl;
  }

  void open()
  {
    cout<< "I am opening the doors" << endl;
  }
};

class Car
{
  public:
  Wheels* wheels;
  Engine engine;
  Doors* doors;
};

int main()
{
  Wheels wheels;
  Doors doors;

  Car car;
  car.wheels = &wheels;
  car.doors = &doors;

  car.wheels->spin();
  car.engine.run();
  car.doors->open();
  return 0;
}