import java.util.*;
 
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
        
        String s[] = sc.next().split("");
        boolean isEasy = true;

        for (int i = 1; i <= s.length; i++) {
            if (i % 2 == 0 && s[i-1].equals("R")) {
                isEasy = false;
            }
            if (i % 2 == 1 && s[i-1].equals("L")) {
                isEasy = false;
            }
        }

        if (isEasy) {
            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