import java.util.Scanner;
public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    String s = sc.next();
    String[] S = s.split("");
    String str = "";
    for(int i = 0;i < S.length;i++){
      if(!(str.equals("")) && S[i].equals("B")){
        str = str.substring(0, str.length() - 1);
      }
      else if(!(S[i].equals("B"))){
        str += S[i];
      }
    }
    System.out.println(str);
    
  }
}

/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