N = gets.chomp
aryodd = []
aryeven = []
i  = 0

N.length.times do
  if i.odd?
    aryodd.push(N[i])
  else
    aryeven.push(N[i])
  end
  i += 1
end

if !aryodd.include?("R") && !aryeven.include?("L")
  puts "Yes"
else
  puts "No"
end
