input = gets.chomp

odd = ['R', 'U', 'D']
even = ['L', 'U', 'D']

flag = true
for i in 0..input.length - 1
    if i % 2 == 0
        if not odd.include?(input[i])
            flag = false
            break
        end
    else
        if not even.include?(input[i])
            flag = false
            break
        end
    end
end


if flag
    puts "Yes"
else
    puts "No"
end