/* $begin swapadd-c */
int swap_add(int *xp, int *yp)  
{ 
    int x = *xp; 
    int y = *yp; 

    *xp = y; 
    *yp = x; 
    return x + y; 
} 

int caller() 
{ 
    int arg1 = 534; 
    int arg2 = 1057; 
    int sum = swap_add(&arg1, &arg2); 
    int diff = arg1 - arg2; 

    return sum * diff; 
} 
/* $end swapadd-c */