s = gets.chomp.chars
odd = []
even = []
s.each_index do |i|
  if i.even?
    odd << s[i]
  elsif i.odd?
    even << s[i]
  end
end

if odd.include?('L')
  puts 'No'
elsif even.include?('R')
  puts 'No'
else
  puts 'Yes'
end
