import java.util.Scanner;

public class Main {

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

        String s = sc.next();

        sc.close();

        StringBuilder sb = new StringBuilder();

        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == '0') {
                sb.append("0");
            } else if (s.charAt(i) == '1') {
                sb.append("1");
            } else if (sb.length() != 0) {
                sb.deleteCharAt(sb.length() - 1);
            }
        }

        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