let shuffle card_lst a =
  let rec shuffle' idx rest_lst head tail =
    match rest_lst with
    | [] -> head::tail
    | x::xs ->
      let head, tail =
        if idx = a then (x, tail)
        else (head, tail @ [x])
      in
      shuffle' (idx + 1) xs head tail
  in
  shuffle' 0 card_lst (-1) []

let solve n a_lst =
  let card_lst = Array.init n (fun i -> i + 1) |>
                 Array.to_list
  in
  let rec solve' rest_lst result =
    match rest_lst with
    | [] -> result
    | x::xs ->
      let result = shuffle result (x - 1) in
      solve' xs result
  in
  solve' a_lst card_lst |> List.hd

let read_int_int () =
  read_line () |>
  Str.split (Str.regexp_string " ") |>
  List.map int_of_string |>
  fun lst -> (List.nth lst 0, List.nth lst 1)

let () =
  let n, _ = read_int_int ()
  and a_lst = read_line () |>
              Str.split (Str.regexp_string " ") |>
              List.map int_of_string
  in
  solve n a_lst |> string_of_int |> print_endline