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

class Main {
    static final String YES = "Yes";
    static final String NO = "No";

    // Generated by 1.1.5 https://github.com/kyuridenamida/atcoder-tools  (tips: You use the default template now. You can remove this line by using your custom template)
    public static void main(String[] args) throws Exception {
        final Scanner sc = new Scanner(System.in);
        String S;
        S = sc.next();
        solve(S);
    }

    static void solve(String S){
        boolean isEven = true;
        for (char c: S.toCharArray()) {
            if (isEven && c == 'L') {
                System.out.println("No");
                return;
            }
            if (!isEven && c == 'R') {
                System.out.println("No");
                return;
            }
            isEven = !isEven;
        }

        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