import java.io.*; import java.util.*; import java.text.*; import java.math.*; import java.util.regex.*; public class Main { public static void main(String[] args) { final Scanner sc = new Scanner(System.in); final String key = sc.nextLine(); final String text = sc.nextLine(); final StringBuilder sb = new StringBuilder(); final char[] chars = new char[text.length()/2]; for (int i = 0; i < text.length(); i += 2) { chars[i/2] = (char)(key.charAt(i/2%key.length()) ^ (char)Long.parseLong(text.substring(i, i+2), 16)); } System.out.println(new String(chars)); } }