fun main(args: Array<String>) {
    val str = readLine()!!.toString()
    println(questionB(str))
}

fun questionB(str: String): String {
    if (str.length !in 1..100) return "No"

    val odd = setOf('R', 'U', 'D')
    val even = setOf('L', 'U', 'D')

    str.mapIndexed { index, c ->
        if (index % 2 == 0) c in odd else c in even
    }.all { it }.let {
        if (it) return "Yes"
        return "No"
    }
}