ООП Дружественные Функции, Операторы. - C++ - Ответ 816810

#include <vcl>
#pragma hdrstop
#include <iostream>
 
using namespace std;
 
class building {
    int rooms, floors, area;
    public: void set_rooms (int num);
            int get_rooms ();
            friend int mult_two (building b1);
 
};
 
//Производный класс.
class house: public building {
    int bedrooms, baths;
    public: void set_bedrooms (int num);
            int get_bedrooms ();
};
 
void building::set_rooms(int num) {
    rooms=num;
}
 
void house::set_bedrooms(int num) {
    bedrooms=num;
}
 
int house::get_bedrooms() {
    return bedrooms;
}
 
int building::get_rooms() {
    return rooms;
}
 
int mult_two (building b1) {
    return 2*b1.rooms;
}
//---------------------------------------------------------------------------
 
#pragma argsused
int _tmain(int argc, _TCHAR* argv[])
{
    system ("title Temp");
    building b;
    b.set_rooms(25);
    cout <<mult_two (b)<<'\n';
    house h2;
    h2.set_rooms(15);
    cout <<mult_two (h2)<<'\n';
    system ("pause");
    return 0;
}
//---------------------------------------------------------------------------