S = gets.strip.chomp

steppable = true

S.split(//).each_with_index do |char, index|
  if (index+1).odd? # 奇数
    unless ["R", "U", "D"].include?(char)
      steppable = false
      break
    end
  else # 偶数
    unless ["L", "U", "D"].include?(char)
      steppable = false
      break
    end
  end
end

if steppable
  puts "Yes"
else
  puts "No"
end
