import java.util.*;
import java.io.*;

class Main {
	public static void main (String[] args) throws IOException {
	    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
	    String s = in.readLine();
	    
	    String res = "";
	    
	    for (int i = 0; i < s.length(); i++) {
	        char c = s.charAt(i);
	        if (c == '0') {
	            res += "0";
	        }
	        if (c == '1') {
	            res += "1";
	        }
	        if (c == 'B' && res.length() > 0) {
	            res = res.substring(0, res.length() - 1);
	        }
	    }
	    System.out.println(res);
	    
	    in.close();
	}
}
/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