s=gets.chomp.split("").map &:to_s
s.each_with_index do |si,i|
  if i%2==0
    unless ["R","U","D"].include?(si)
      puts "No"
      exit
    end
  else
    unless ["L","U","D"].include?(si)
      puts "No"
      exit
    end
  end
end
puts "Yes"