import java.util.*;
public class Main {
    public static void main(String[] args) {
      Scanner sc = new Scanner(System.in);
      String s = sc.next();
      String ans = "";
      for(int i=0;i<s.length();i++){
        if(s.charAt(i)=='0'){
          ans += "0";
        }else if(s.charAt(i)=='1'){
          ans += "1";
        }else{
          if(!ans.isEmpty()){
          	ans = ans.substring(0,ans.length()-1);
          }
        }
      }     
        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