s = gets.chomp.split('')
odd = []
even = []
(0..s.length-1).each do |n|
    if n%2 ==0
        odd << s[n]
    else
        even << s[n]
    end
end

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