import java.util.*;
import java.lang.*;

public class Main {
    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        boolean ans = true;
        
        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i);
            if ((i % 2 == 0 && c == 'L') || (i % 2 == 1 && c == 'R')) {
                ans = false;
                break;
            }
        }
        System.out.println(ans ? "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