open monad io number string

:::IO

take_numbers 0 xs = do
  return $ iter xs
  where f x = sqrt (toSingle x) + 5.0 * (x ** 3.0)
        p x = x < 400.0
        iter [] = return ()
        iter (x::xs)
          | p res = do
              putStrLn (format "f({0}) = {1}" x res)
              iter xs
          | else = do
              putStrLn (format "f({0}) :: Overflow" x)
              iter xs
          where res = f x
take_numbers n xs = do
  x <- readAny
  take_numbers (n - 1) (x::xs)

do
  putStrLn "Please enter 11 numbers:"
  take_numbers 11 []