let () =
  Scanf.scanf "%s\n" @@ fun s ->
  let ans = ref true in
  let check i c =
    if i mod 2 = 1 then
      if c = 'R' || c = 'U' || c = 'D' then () else ans := !ans && false
    else
      if c = 'L' || c = 'U' || c = 'D' then () else ans := !ans && false in
  StringLabels.iteri (fun i c -> check (i+1) c) s;
  Printf.printf "%s\n" (if !ans then "Yes" else "No")