СРОЧНО!! НА ПИТОНЕ. :dddd

def f(n: int, int=False) -> bool:

   if 0 > n >= 1000: return False

   if n % 2 == 0: result = n/2

   if n % 2 == 1: result = f(n-1, int=True)+3

   if int: return result

   if result == 18: return True

   return False

def main() -> None:

   print(sum([f(n) for n in range(1001)]))

if __name__ == "__main__":

   main()