fun main(args: Array<String>) {
  val S = readString()
  var flag = true
  S.forEachIndexed { index, c ->
    if (index % 2 == 0) {
      if (c != 'R' && c != 'U' && c != 'D') flag = false
    } else {
      if (c != 'L' && c != 'U' && c != 'D') flag = false
    }
  }
  println(if (flag) "Yes" else "No")
}

fun gcd(a: Int, b: Int): Int = if (a < b) gcd(b, a) else if (b == 0) a else gcd(b, a % b)
fun gcd(a: Long, b: Long): Long = if (a < b) gcd(b, a) else if (b == 0L) a else gcd(b, a % b)
fun lcm(a: Int, b: Int): Int = (a * b) / gcd(a, b)
fun lcm(a: Long, b: Long): Long = (a * b) / gcd(a, b)

fun readString() = readLine()!!
fun readInt() = readLine()!!.toInt()
fun readInts() = readLine()!!.split(" ").map { it.toInt() }
fun readLongs() = readLine()!!.split(" ").map { it.toLong() }
