s = gets.strip.split('')

s.each_with_index do |chr, i|
  if (i+1).odd?
    unless ['R','U','D'].include?(chr)
      puts 'No'
      exit
    end
  else
    unless ['L','U','D'].include?(chr)
      puts 'No'
      exit
    end
  end  
end

puts 'Yes'
