open Num

let rec solve w d =
  if d =/ Int 1 then w
  else
    let y = quo_num w (d **/ Int 2) in
    solve (w -/ y) (d -/ Int 1)

let () =
  let w = read_line () |> num_of_string
  and d = read_line () |> num_of_string in
  solve w d
  |> string_of_num
  |> print_endline