import java.util.Scanner;

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

    final String s = scanner.nextLine();

    StringBuilder o = new StringBuilder();
    for (char c: s.toCharArray()) {
      switch (c) {
        case '0':
        case '1':
          o.append(c);
          break;
        case 'B':
          if (o.length() > 0) {
            o.deleteCharAt(o.length() - 1);
          }
      }
    }

    System.out.println(o.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