import java.util.Scanner;
public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		char[] s = sc.next().toCharArray();
		StringBuffer sb = new StringBuffer();
		for (int i=0; i<s.length; i++) {
			if (s[i] == '0') sb.append("0");
			else if (s[i] == '1') sb.append("1");
			else if (s[i] == 'B') {
				if (sb.length() > 0)
					sb.delete(sb.length()-1, sb.length());
			}
		}
		System.out.println(sb.toString());
	}
}

/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