import java.util.Scanner;

public class Main {
	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		for(int i = 0 ; i < s.length() ; i++) {
			if((i + 1) % 2 == 0) {
			if(s.charAt(i) == 'R') {
				System.out.println("No");
				return;
				}
				}
			else {
				if(s.charAt(i) == 'L') {
					System.out.println("No");
					return;
					}
					}
			}

		sc.close();
		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