let solve k ar =
  let flag = ref false in
  for i = 0 to 4 do
    for j = 0 to 4 do
      if abs (ar.(i) - ar.(j)) > k then flag := true
    done;
  done;
  if !flag then ":(" else "Yay!"

let _ =
  let ar = Array.make 5 0 in
  for i = 0 to 4 do
    Scanf.scanf "%d\n" (fun a -> ar.(i) <- a)
  done;
  let k = Scanf.scanf "%d\n" (fun k -> k) in
  solve k ar |> print_string
