s = gets.chomp
o = []
e = []
s.chars.each_with_index do |c, i|
  if i % 2 == 0
    o.push c
  else
    e.push c
  end
end
puts o.all?{|c| ['R', 'U', 'D'].include? c} && e.all?{|c| ['L', 'U', 'D'].include? c} ? 'Yes' : 'No'
