Penggunaan friend class

#include
#include

using namespace std;

class CSquare;

class CRectangle{
int width, height;

public:
int area(){return (width * height);}
void convert (CSquare a);
};

class CSquare{
private:
int side;
public:
void set_side(int a){side=a;}
friend class CRectangle;
};

int main()
{

CSquare sqr;
CRectangle rect;
sqr.set_side(4);
rect.convert(sqr);
cout <<<

system(“PAUSE”);
return EXIT_SUCCESS;
}

void CRectangle::convert(CSquare a){
width=a.side;
height=a.side;
}