import java.util.Scanner;
public class Main{
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        String s=in.nextLine();
        int check=0;
        for (int i = 0; i < s.length(); i++) {
            if(s.charAt(i)=='R' && i%2!=0){
                check++;
                break;
            }else if(s.charAt(i)=='L' && i%2==0){
                check++;
                break;
            }
        }
        if(check==0){
            System.out.println("Yes");
        }else{
            System.out.println("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