import java.util.Scanner;

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

		for (int i = 0; i < N.length(); i++) {
			char c = N.charAt(i);
			if (i % 2 == 0) {
				if (c =='L') {
					System.out.println("No");
					break;
				}
			}else {
				if (c =='R') {
					System.out.println("No");
					break;
				}
			}
			if (i == N.length() - 1) {
				System.out.println("Yes");
			}
		}
	}

}
/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