S = gets.chomp
flag = 0
for i in 0..(S.length-1)
    if(i%2 == 0)
        if S[i] == 'R' || S[i] == 'U'|| S[i] == 'D'
        else
            flag = 1
            break
        end
    else
        if S[i] == 'L' || S[i] == 'U'|| S[i] == 'D'
        else
            flag = 1
            break
        end
    end
end
if flag == 1
    puts "No"
else
    puts "Yes"
end