import java.util.Scanner;

public class Main{
    public static void main(String[] args){
	Scanner scan = new Scanner(System.in);

	/* 入力 */
	String s = scan.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.length() != 0){
		    ans = ans.substring(0,ans.length()-1);
		}
	    }
	}

	/* 出力 */
	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