fun main(args: Array<String>){
  val S = readLine()!!
  for( i in S.indices ){
    if( S[i] == 'U' || S[i] == 'D' || i%2 == 1 && S[i] == 'L' || i%2 == 0 && S[i] == 'R')
      continue
    println("No")
    return
  }
  println("Yes")
}
