import java.util.*;


class Main{
  
      
  
  
	public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
      
      String s = sc.next();
      StringBuilder ans = new StringBuilder();
      
      for(int i=0;i<s.length();i++){
      	if(s.charAt(i)=='0'){
        	ans.append('0');
        } else if(s.charAt(i)=='1'){
        	ans.append('1');
        } else {
          if(ans.length() > 0){
        	ans.deleteCharAt(ans.length()-1);
          }
        }
      }
      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