import java.util.Scanner;

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

        String s = sc.next();

        System.out.println(solve(s));

        sc.close();
    }

    static String solve(String s) {
        StringBuilder result = new StringBuilder();
        for (char ch : s.toCharArray()) {
            if (ch == 'B') {
                if (result.length() != 0) {
                    result.deleteCharAt(result.length() - 1);
                }
            } else {
                result.append(ch);
            }
        }

        return result.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