S = gets.chomp

for i in 0..S.length - 1
  if !((i + 1) % 2 == 1 && (S[i] == "R" || S[i] == "U" || S[i] == "D")) && !((i + 1) % 2 != 1 && (S[i] == "L" || S[i] == "U" || S[i] == "D"))
    puts "No"
    exit
  end
end

puts "Yes"
