let solve n =
  let rec solve' cur_n result =
    if cur_n <= 0 then result
    else
      let next_n = cur_n lsr 1
      and next_result = if cur_n land 1 = 1 then result + 1
                        else result
      in
      solve' next_n next_result
  in
  solve' n 0

let () =
  let n = read_line () |> int_of_string in
  solve n |> string_of_int |> print_endline