
object Main extends App {

  val s = scala.io.StdIn.readLine()

  def solve(): String = {
    for(i <- 0 until s.length) {
      if (i % 2 == 0) {
        if(s(i) == 'L') return "No"
      } else {
        if(s(i) == 'R') return "No"
      }
    }
    return "Yes"
  }

  println(solve)

}