import java.util.Scanner;

public class Main {
	public static void main(String[] args)  {
		Scanner sc = new Scanner(System.in);
		String[] s = sc.nextLine().split("");
		sc.close();
		String ans = "";
		for(int i = 0; i < s.length; i++) {
			if(s[i].equals("B")) {
				if(!(ans.equals(""))) {
					ans = ans.substring(0,ans.length()-1);
				}
			}else {
				ans += s[i];
			}
		}
		System.out.println(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