import java.util.*;
import static java.lang.System.*;
import java.math.*;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		char[] c = sc.next().toCharArray();
		String ans = "Yes";
		
		for(int i =0; i < c.length; i++) {
			if(i % 2 == 0) {//奇数
				if(c[i] == 'L') {
					ans = "No";
					break;
				}				
			} else {
				if (c[i] == 'R') {
					ans = "No";
					break;
				}
			}
		}
		out.println(ans);
		
	}
}
/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