let to_list str =
  let rec doit i acc =
    if i < 0 then acc
    else doit (i - 1) (String.get str i :: acc) in
  doit (String.length str - 1) []

let () =
  let a, b = Scanf.scanf "%s %s " (fun a b -> a, b) in
  let sort l = List.fast_sort (fun x y -> Char.code x - Char.code y) l in
  let a = to_list a |> sort in
  let b = to_list b |> sort in
  print_endline (if a = b then "YES" else "NO")