split_to_ints.ml

let char_0 = Char.code '0'

let split n s =
  let len_s = String.length s in
  let res = Array.make n 0 in

  let rec slide pos =
    if pos < len_s && s.[pos] <> ' ' then
      pos + 1 |> slide
    else pos
  in

  let rec to_int i over n =
    if i < over then
      let n = n * 10 + Char.code s.[i] - char_0 in
      to_int (i + 1) over n
    else
      n
  in

  let rec loop i j =
    if i < n && j < len_s then
      let j' = slide j in
      if s.[j] = '-' then
        res.(i) <- -1 * to_int (j + 1) j' 0
      else
        res.(i) <- to_int j j' 0;
      loop (i + 1) (j' + 1)
  in

  loop 0 0;
  res