# def easy_step
#   # p gets().chomp.split("")
#   steps = gets().chomp.split("")
  
#   steps.each_with_index do |step, index|
#     next if (index.modulo(2) > 0 && step != "R") || (index.modulo(2) == 0 && step != "L")
#     return false
#   end

#   steps.size() > 0 ? true : false
# end

# easy_step ? p("Yes") : p("No")

s = gets.chomp.split('')
s.length.times do |n|
  if n.odd? && s[n] == 'R' || n.even? && s[n] == 'L'
    puts 'No'
    exit
  end
end

puts 'Yes'