def get_int
  gets.chop.to_i
end

def get_ints
  gets.chop.split.map(&:to_i)
end

def get_double
  gets.chop.to_f
end

def get_str
  gets.chop
end

def get_strs
  gets.chop.split
end

def main
  s = get_str
  0.upto(s.size - 1) do |i|
    c = s[i]
    if i % 2 == 1
      if not ["L", "U", "D"].include?(c)
        puts "No"
        exit
      end
    else
      if not ["R", "U", "D"].include?(c)
        puts "No"
        exit
      end
    end
  end
  puts "Yes"
end

if __FILE__ == $0
  main
end
