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

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        String s = sc.next();
        int len = s.length();

        String ans = "Yes";

        for (int i = 1; i<=len; i++){
            if (i%2 == 0 && s.charAt(i-1) == 'R') {
                ans = "No";
                break;
            }
            else if (i%2 == 1 && s.charAt(i-1) == 'L'){
                ans = "No";
                break;
            }
        }
        System.out.println(ans);
    }
}
/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