PROGRAM FOR UNARY OPERATOR OVERLOADING USING FRIEND FUNCTION

//program for operator overloading of unary op using friend fn
#include<iostream.h>
#include<conio.h>
class c
{
  int x,y,z;
  public:
      void display()
      {
cout<<x<<" "<<y<<" "<<z<<endl;
      }
      void getdata(int a,int b,int c)
      {
x=a;
y=b;
z=c;
      }
      friend void operator -(c &);
};
void operator -(c &r)
{
 r.x=-r.x;
 r.y=-r.y;
 r.z=-r.z;
}
void main()
{
  c s;
  clrscr();
  s.getdata(-10,90,100);
  s.display();
  -s;
  s.display();
  getch();
}