习题5-14

#include "stdafx.h"
#include<iostream>
using namespace std;

class Boat;
class Car {
private:
    int weight;
public:
    Car(int j) {
        weight = j;
    }
    friend int getTotalWeight(Car &aCar, Boat &aBoat);
};

class Boat {
private:
    int weight;
public:
    Boat(int j) {
        weight = j;
    }
    friend int getTotalWeight(Car &aCar, Boat &aBoat);
};

int getTotalWeight(Car &aCar, Boat &aBoat) {
    return aCar.weight + aBoat.weight;
}

int main()
{
    Car c1(4);
    Boat b1(5);
    cout << "The total weight:" << getTotalWeight(c1, b1) << endl;
    return 0;
}