s = gets.split("")
count = 1
ans = 0

s.each do |i|
  if count % 2 == 1
    if i == "L"
      ans += 1 
    end
  else
    if i == "R"
      ans += 1
    end
  end
  count += 1
end

puts ans == 0 ? "Yes" : "No"