# N, A, B = gets.split(" ").map(&:to_i)
S = gets.chomp
# N = gets.to_i

ok = true
S.split(//).each_with_index do |ch, i|
    ok = false if i%2 == 0 && ch == 'L'
    ok = false if i%2 == 1 && ch == 'R'
end

puts ok ? 'Yes' : 'No'
