s = gets
as = s.split("")
i = 1
ans = "Yes"
as.each{ |n|
    if (i % 2 == 0 && !(n == "L" || n == "U" || n == "D"))
      ans = "No"
    elsif (i % 2 != 0 && !(n == "R" || n == "U" || n == "D"))
      ans = "No"
    end
    i += 1
}
puts "#{ans}"