include <CarFactory.h>
  
  // Initialize the count to zero when the factory is created.
  CarFactory::CarFactory() : mNumCarsInProduction(0) {}
  
  // Increment the number of cars in production and return the 
  // new car.
  Car* CarFactory::requestCar()
  {
    mNumCarsInProduction++;
    return createCar();
  }
  
  int CarFactory::getNumCarsInProduction() const
  {
    return mNumCarsInProduction;
  }
  
  Car* FordFactory::createCar()
  {
    return new Ford();
  }
  
  Car* ToyotaFactory::createCar()
  {
    return new Toyota();
  }