import java.util.LinkedList;
import java.util.Scanner;

public class Main {

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

		String[] sArray = s.split("");

		LinkedList<String> ansList = new LinkedList<>();

		for(int i = 0; i < s.length(); i++){
			if(sArray[i].equals("1")) {
				ansList.add("1");
			} else if(sArray[i].equals("0")) {
				ansList.add("0");
			} else if(sArray[i].equals("B") && ansList.size() != 0){
				ansList.removeLast();
			}
		}
		
		for(String ans: ansList){
			System.out.print(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