Friend class is also used to
access private members of the class in another class. Here we use forward
declaration of class.
#include<conio.h>
#include<iostream>
using namespace std;
class square;//Forward declaration of class
class rectangle
{
int hieght;
int
width;
public:
rectangle(){hieght=0,width=0;}
rectangle(int
a, int b){hieght=a,width=b;}
void
convert(square s);// class sqaure is called in the rectangle class.
int
area()
{
return
hieght*width;
}
};
class square
{
friend
class rectangle; //declaring rectangle as a friend class
int
side;
public:
square(int
a){side=a;}
};
void rectangle::convert(square s)
{
hieght=s.side;
width=s.side;
}
int main()
{
rectangle
rect;
square
sqr(4);
rect.convert(sqr);
cout<<"area
of square :"<<rect.area();
getch();
return
0;
