s = gets.chomp.split('')
s.each.with_index(1) do |d, i|
  if i.odd?
    unless ['R', 'U', 'D'].include?(d)
      puts 'No'
      exit
    end
  else
    unless ['L', 'U', 'D'].include?(d)
      puts 'No'
      exit
    end
  end
end
puts 'Yes'
