import java.util.Scanner;
 
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        boolean flg = true;
        for (int i = 0; i < S.length(); i++) {
        	if ((i%2 == 0 && S.charAt(i) == 'L') || 
        			(i%2 != 0 && S.charAt(i) == 'R')) {
        		flg = false;
        	} 
        }
        System.out.println(flg ? "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