#!/bin/bash

read S

S=$(echo $S | awk -v FS='' '{for (i = 1; i <= NF; i++) print $i;}')
i=0
for c in $S; do
  i=$(expr $i + 1)
  # even
  if [ $(expr $i % 2) -eq 0 ]; then
    if [ $c != 'L' -a $c != 'U' -a $c != 'D' ]; then
      echo 'No'
      exit
    fi
  # odd
  else
    if [ $c != 'R' -a $c != 'U' -a $c != 'D' ]; then
      echo 'No'
      exit
    fi
  fi
done
echo 'Yes'