rat f3 (int a int b rat r){
  return [(a + num r) / (b + denom r)];
}

rat f2 (bool b rat x rat y){
  int x1 = num x;
  int x2 = denom x;
  rat res = call f3(x1 x2 y);
  return res;
}

int f1 (int i rat r int n){
  rat r2 = call f2(true r [i/n]);
  return denom r2;
}

test{
  int x = call f1 (13 [4/11] 17);
  print x;
}