import java.util.Scanner;

public class Main {

	public static void main (String[] args) {
		Scanner scan = new Scanner(System.in);
		String[] s = scan.next().split("");
		String result ="";
		for(String w:s) {
			if(w.equals("0") || w.equals("1")) result+=w;
			if(w.equals("B") && result.length()>0)result = result.substring(0, result.length()-1);
		}
		System.out.println(result);
	}

}
/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