object Main extends App {
  import scala.io.StdIn._
  val s = readLine()
  val res = s.zipWithIndex.map { x =>
    if(x._2 % 2 == 0) {
      "RUD".contains(x._1)
    } else {
      "LUD".contains(x._1)
    }
  }
  println( if (res.contains(false)) "No" else "Yes")
}