S = gets.chomp

if S.chars.select.with_index { |c, i| i.even? }.all? { |c, i| ['R', 'U', 'D'].include?(c) } && S.chars.select.with_index { |c, i| i.odd? }.all? { |c, i| ['L', 'U', 'D'].include?(c) }
  puts 'Yes'
else
  puts 'No'
end
