(* 2.3 list_upcase *)

(* 1.1 char_upcase *)

let rec char_upcase x =
  if x < 'a' || x > 'z'
  then
    print_char x
  else
    print_char (Char.chr((Char.code x)-(Char.code 'a' - Char.code 'A')))
      ;;

(* 1.2 string_iter *)

let string_iter f s =
  let rec s_iter f s = function
      n when n = String.length s -> ()
    | n -> (f s.[n]) ; (s_iter f s (n+1))
  in s_iter f s 0 ;;

(* 1.3 string_upcase *)

let string_upcase x = string_iter char_upcase x ;;

(* 1.4 list_upcase *)

let rec list_upcase liste =
  let rec list_iter f = function
      [] -> ()
    | e::l -> f e ; print_newline (); list_iter f l
  in list_iter string_upcase liste ;;



 let make_liste =
  let length = Array.length Sys.argv
  in
  let rec aux = function
      n when n = length  -> []
    | n -> Sys.argv.(n)::aux (n+1)
in aux 1  ;;

let _= list_upcase make_liste ;;