let () =
  let hh = 3600 in
  let mm = 60 in
  let time_calc time =
      let hour = time / hh in
      let minu = (time-hour*hh)/mm in
      let scnd = (time-hour*hh-minu*mm) in
      print_int hour ;
      print_string ":" ;
      print_int minu ;
      print_string ":" ;
      print_int scnd ; 
      print_string "\n"
  in
    Scanf.scanf "%d" time_calc