object Main {
  def main(args: Array[String]) {
    val odd = Set[Char]('R', 'U', 'D')
    val even = Set[Char]('L', 'U', 'D')
    for((c, i) <- scala.io.StdIn.readLine() zip (Stream from 1)) {
      if (!(i % 2 == 1 && (odd contains c) || i % 2 == 0 && (even contains c))) {
        println("No")
        return
      }
    }
    println("Yes")
  }
}
