module S = Set.Make (struct
  type t = char
  let compare x y = Char.code x - Char.code y
end)

let () =
  let a, b = Scanf.scanf "%s %s " (fun a b -> a, b) in
  let rec doit x i l set =
    if i = l then set
    else S.add x.[i] set |> doit x (i + 1) l in
  let s = doit a 0 (String.length a) S.empty in
  let t = doit b 0 (String.length b) S.empty in
  print_endline (if S.equal s t then "YES" else "NO")