import java.util.Scanner;

class Main {
    public static void main(String[] args) {
	Scanner sc = new Scanner(System.in);

	String S = sc.next();
	String s[] = S.split("");

	boolean bl = true;
	for (int i = 0; i < s.length; i++) {
	    if (i % 2 == 1) {
		if (s[i].equals("R")) {
		    bl = false;
		    break;
		}
	    } else {
		if (s[i].equals("L")) {
		    bl = false;
		    break;
		}
	    }
	}

	if (bl)
	    System.out.println("Yes");
	else
	    System.out.println("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