import java.util.*;
public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        StringBuilder A = new StringBuilder();
        for(int i = 0;i < S.length();i++){
            switch (S.charAt(i)) {
                case '0':
                A.append(S.charAt(i));
                break;
                case 'B':
                if(A.length() != 0){
                    A.setLength(A.length()-1);
                }
                break;
                case '1':
                A.append(S.charAt(i));
                break;
            }
        }
        System.out.println(A);
        
    }
}

/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