let n = read_int ()
let s = read_line ()

let rec f i ans =
  if i = 4 then print_endline "-1"
  else
    let rec g j t =
      if j = n then t = i
      else
        let f0 = t lsr 1
        and f1 = t land 1 in
        let f2 = f0 lxor if s.[j] = 'o' then 0 else 1 in
        (
          ans.(j) <- if f2 = 0 then 'S' else 'W';
          g (j + 1) (((f1 lxor f2) lsl 1) lor f2)
        )
    in
    if g 0 i then
      let rec h j =
        if j < n - 1 then (
          print_char ans.(j);
          h (j + 1)
        )
      in (print_char ans.(n-1); h 0)
    else f (i + 1) ans

let () = f 0 (Array.make n ' ')
