let rec fact = function
    |1 -> 1
    | n -> n * fact (n-1) ;;

let print_fact n =
  Printf.printf "factorielle %i = %i\n" n (fact n)

let main () = 
  begin 
    print_fact 5 ;
    print_newline () ;
    exit 0 ;
  end

let _ = main ()