require 'pp'

def gets; ARGF.gets; end

class Solver

  def initialize
  end

  def main
    s = gets.chomp

    s.chars.each_with_index do |c, i|
      if (i+1).even?
        if c == 'R'
          puts "No"
          return
        end
      else
        if c == 'L'
          puts "No"
          return
        end
      end
    end

    puts "Yes"
  end
end

if __FILE__ == $0
  Solver.new.main
end
