import java.util.Scanner;

public class Main {
  
  	private final static Scanner sc = new Scanner(System.in);
    public static void main (String [] args) {
      boolean klappts = true;
      String S = sc.next();
      int N = S.length();
      for(int i = 0; i < N; i++) {
      	if((i % 2 == 0 && S.charAt(i) == 'L') || (i % 2 == 1 && S.charAt(i) == 'R')) {
          klappts = false;
          break;
        }
      }
      if (klappts) {
        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