#  = gets.chomp.to_i
# A, B, C = gets.chomp.split.map(&:to_i)
S = gets.chomp

r = true
S.chars.each.with_index do |c, i|
  i += 1
  
  if (i % 2 == 1) # odd
    if !['R', 'U', 'D'].include?(c)
      r = false
      break
    end
  else # odd
    if !['L', 'U', 'D'].include?(c)
      r = false
      break
    end
  end
end

if r
  print "Yes\n"
else
  print "No\n"
end