S=gets.chomp

flag=true
S.length.times do |i|
  str = S[i]
  if (i+1) % 2 == 0
    if str!="L" && str!="U" && str!="D"
      flag = false
      break
    end
  else
    if str!="R" && str!="U" && str!="D"
      flag = false
      break
    end
  end
end

if flag
  puts "Yes"
else
  puts "No"
end