Submission #432519

---

Source Code Expand

module String = struct
  include String
  let to_list s = 
    let rec to_list_aux acc = function
      | 0 -> acc
      | n -> to_list_aux (s.[n - 1] :: acc) (n - 1) in
    to_list_aux [] (String.length s)
end

let () =
  let s = String.to_list @@ Scanf.scanf "%s\n" (fun s -> s) in
  let n = Scanf.scanf "%d" (fun n -> n) in
  List.map (fun c ->
    List.map (fun c' -> String.make 1 c ^ String.make 1 c') s) s
      |> List.concat
      |> List.sort compare
      |> (fun l -> List.nth l (n - 1))
      |> print_endline

Submission Info

Judge Result