program to show the basics of inline function in oops

#include<iostream.h>
#include<conio.h>
class rectangle
{
 int a,b;
 public:
       void setdata(int x,int y)
       {
    a=x;
    b=y;
    }
    void show()
    {
    cout<<"area of rectangle is "<<a*b;
    }
};
void main()
{
 clrscr();
 rectangle r1,r2,r3;
 r1.setdata(7,6);
 r1.show();
 cout<<endl;
 r1.setdata(5,5);
 r2.setdata(10,10);
 r2.show();
 cout<<endl;
 r1.show();
 getch();
 }