import java.util.Scanner

object Main {
  def main(args: Array[String]): Unit = {
    val sc = new Scanner(System.in)
    val s = sc.next()
    val odd = Seq('R', 'U', 'D')
    val even = Seq('L', 'U', 'D')
    for (i <- 0 until s.length) {
      if (i % 2 == 0) {
        if (odd.indexOf(s(i)) == -1) {
          println("No")
          return
        }
      } else {
        if (even.indexOf(s(i)) == -1) {
          println("No")
          return
        }
      }
    }
    println("Yes")
  }
}