s = gets.chomp

s.chars.each.with_index(1) do |c, i|
  if i.odd?
    unless %w(R U D).include?(c)
      puts 'No'
      exit
    end
  else
    unless %w(L U D).include?(c)
      puts 'No'
      exit
    end
  end
end
puts 'Yes'