import java.util.Scanner;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String str = sc.nextLine();
    StringBuilder ans = new StringBuilder("");
    for(int i = 0; i < str.length(); i++) {
      char ch = str.charAt(i);
      switch(ch) {
        case '0':
        case '1':
          ans.append(ch);
          break;
        case 'B':
          if(ans.length() != 0) {
            ans.deleteCharAt(ans.length() - 1);
          }
          break;
      }
    }
    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