import java.util.*

fun main(args: Array<String>) {
    val scanner = Scanner(System.`in`)
    val s = scanner.next()
    var count = 1
    var check = true
    for(item in s){
        if(count % 2 !== 0 && (item != 'R' && item != 'U' && item != 'D')) check = false
        else if(count % 2 === 0 && (item != 'L' && item != 'U' && item != 'D')) check = false
        if(!check) {
            println("No")
            return
        }
      count++
    }
    println("Yes")
}