// D test program gcd.d  CSE413 6/99

// Read two positive numbers and print their greatest common divisor

// = gcd of x & y provided x, y >= 0
int gcd(x,y) {
  while (! x == y)
    if (x > y)
	  x = x-y;
	else
	  y = y-x;
  return x;
}

int main() { int a,b; int ans;
  a = get(); b=get() ; 
  ans = gcd(a,b);
  ans = put(ans);
  return(((17)));
}