/******************************************************************************

                            Online Java Compiler.
                Code, Compile, Run and Debug java program online.
Write your code in this editor and press "Run" button to execute it.

*******************************************************************************/
import java.util.Scanner;
 class Main
{
	public static void main(String[] args) {
		
		Scanner sc = new Scanner(System.in);
		
		String input = sc.nextLine();
		
		StringBuilder output = new StringBuilder();
		
		for (int i=0; i<input.length(); ++i) {
		    
		    if (input.charAt(i) != 'B') {
		        output.append(input.charAt(i));
		    }else {
		        int len = output.length();
		        if (len > 0) {
		            output.deleteCharAt(len-1);
		        }
		    }
		}
		
		sc.close();
		System.out.println(output);
	}
}

/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