/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		Scanner s = new Scanner(System.in);
		String firstString = s.nextLine();
		String secondString = s.nextLine();
 
		Ideone id = new Ideone();
		id.matchStrings(firstString,secondString);
 
	}
 
	void matchStrings(String one,String two)
	{
		if(two.length() == 0 || two == null || one.length()==0 || one ==null)
		System.out.println(one);
		else
		{
 
		 String match = one.replace(String.valueOf(two.charAt(0)),"");
		 matchStrings(match,two.substring(1,two.length()));
		}
	}
}

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YWJjZApjZA==

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