车船总重

#include<iostream>
using namespace std;
class Car;
class Boat
{
	friend class Car;
public:
	friend int getTotalWeight(Boat &weight1,Car &weight2);
	Boat(int B_weight)
	{
		weight1=B_weight;
	}
	Boat(Boat& boat1)
	{
		weight1=boat1.weight1;
		cout <<"Calling the copy constructor"<<endl;
	}
private:
	int weight1;
};
class Car
{
	friend class Boat;
public:
	friend int getTotalWeight(Boat &weight1,Car &weight2);
	Car(int C_weight)
	{
		weight2=C_weight;
	}
	Car(Car& car1)
	{
		weight2=car1.weight2;
		cout <<"Calling the copy constructor"<<endl;
	}
private:
	int weight2;
};
int getTotalWeight(Boat& b,Car& c)
{
	return b.weight1+c.weight2;
}
int main()
{
	Boat boat1(1000);
	Car car1(500);
	cout<<"allweight:"<<getTotalWeight(boat1,car1)<<endl;
	return 0;
}