let read_line () =
  try
    Some (read_line ())
  with End_of_file -> None

let rec initial last_was_empty =
  match read_line () with
  | None -> ()
  | Some "(* begin thide *)" ->	thide last_was_empty
  | Some "" ->
    if not (last_was_empty) then
      print_newline ();
    initial true
  | Some line ->
    let idx = try Some (String.index line '(') with Not_found -> None in
    match idx with
    | Some idx ->
      if String.length line > idx+1 && line.[idx+1] = '*'
         && not (String.length line > idx+4 && String.sub line (idx+2) 3 = " EX") then
        if line.[String.length line - 2] = '*' && line.[String.length line - 1] = ')' then
          initial last_was_empty
        else
          comment 1 last_was_empty
      else begin
        print_endline line;
        initial false
      end
    | None ->
      print_endline line;
      initial false

and comment count last_was_empty =
  match read_line () with
  | None -> ()
  | Some line ->
    if String.length line >= 2 && line.[0] = '(' && line.[1] = '*' then
      if String.length line >= 2 && line.[String.length line - 2] = '*'
         && line.[String.length line - 1] = ')' then
        comment count last_was_empty
      else
        comment (count+1) last_was_empty
    else if String.length line >= 2 && line.[String.length line - 2] = '*'
            && line.[String.length line - 1] = ')' then
      if try
          let idx = String.index line '(' in
          idx < String.length line - 1 && line.[idx + 1] = '*'
        with Not_found -> false then
        comment count last_was_empty
      else if count = 1 then
        initial last_was_empty
      else
        comment (count-1) last_was_empty
    else
      comment count last_was_empty

and thide last_was_empty =
  match read_line () with
  | None -> ()
  | Some "(* end thide *)" -> initial last_was_empty
  | Some _ -> thide last_was_empty

let () = initial false