import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String S = sc.next();
		sc.close();
		char[] ch = S.toCharArray();
		boolean bool = true;
		for(int i = 0;i < ch.length;i++) {
			if(((i+1)%2==0 && ch[i] =='R') || ((i+1)%2==1 && ch[i] =='L')) {
				bool = false;
			}
		}
		System.out.println(bool ? "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