import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
/**
* @date 2021-8-20 - 17:48
* Created by Salmon
*/
public class Main1093 {
public static void main(String[] args) throws IOException {
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
//v1 超时或者内存超限 不过写的很爽1min的事情
// String s1 = bufferedReader.readLine();
// String s2 = bufferedReader.readLine();
// bufferedReader.close();
// String[] strings = (s1 + s2).split("");
// StringBuilder res = new StringBuilder();
// for (int i = 0; i < strings.length; i++) {
// if(!res.toString().contains(strings[i])){
// res.append(strings[i]);
// }
// }
// System.out.println(res);
//v2 稳过
String s1 = bufferedReader.readLine();
String s2 = bufferedReader.readLine();
bufferedReader.close();
char[] chars = (s1 + s2).toCharArray();
int[] ASC = new int[127];
for (int i = 0; i < chars.length; i++){
if(ASC[chars[i]] == 0){
System.out.print(chars[i]);
ASC[chars[i]]++;
}
}
}
}