import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String s = scanner.nextLine();

        String odd = "RUD";
        String even = "LUD";
        boolean rslt = true;

        for (int i = 1; i <= s.length(); i++) {
            if (i%2==0) {
                if (!even.contains(s.substring(i-1, i))) {
                    rslt = false;
                    break;
                }
            } else {
                if (!odd.contains(s.substring(i-1, i))) {
                    rslt = false;
                    break;
                }
            }
        }
        System.out.println(rslt? "Yes": "No");
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz