swap two integers without a third variable

#include<iostream.h>

#include<conio.h>

void main()
{
int x,y;
cout<<"\n Enter 2 integers respectively:";
cin>>x>>y;


clrscr();


cout<<"\n The original value in x = " << x << " and  y = " << y;


x = x+y;
y = x - y;
x = x - y;


cout<<"\n The swaped value in x = " << x << " and y = " << y;
getch();
}