object Main extends App{
    val s = io.StdIn.readLine

    val odd = for(i <- (1 to s.length).filter(_ % 2 == 0)) yield s(i - 1)
    val even = for(i <- (1 to s.length).filter(_ % 2 == 1)) yield s(i - 1)
    println(if(odd.contains('R') || even.contains('L')) "No" else "Yes")
}