S=gets.chomp.chars
EVEN=S.select.with_index{|s,idx| (idx-1).even?}.uniq
ODD=S.select.with_index{|s,idx| (idx-1).odd?}.uniq

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