import java.util.Scanner;

public class Main {
    public static void main(final String[] args) {
        final Scanner sc = new Scanner(System.in);
        final char[] s = sc.next().toCharArray();
        for (int i = 0; i < s.length; i++) {
            if (s[i] == (i%2==0? 'L': 'R')) {
                System.out.println("No");
                return;
            }
        } 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