
fun main(args: Array<String>) {
    val line= readLine()

    var reftOK = true
    var rightOK = true
    for(i in 1..line!!.length){
        val p = line.substring(i-1,i)
        if((i.mod(2)) == 0 && p == "R"){
            //println("R:false")
            reftOK = false
        }else if( i.mod(2) == 1 && p == "L"){
            //println("L:false")
            rightOK = false
        }else{
            //println("OK")
        }
    }

    if(rightOK && reftOK){
        println("Yes")
    }else{
        println("No")
    }
}