#include<iostream>
using namespace std;
class point
{
private:
int x,y;
public:
point(int xx=0,int yy=0)
{x=xx;y=yy;}
void display()
{cout<<"x="<<x<<",y="<<y<<endl;}
friend point operator++(point &p);
};
point operator ++(point &p)
{
++p.x;
++p.y;
return p;
}
int main()
{
point a(1,2);
++a;
a.display();
return 0;
}