#include <iostream>
#include <set>
using namespace std;
#include <string>
#include <vector>
#include <algorithm>
int main()
{
	string s1, s2;
	//要读取空格 采用getline()函数
	getline(cin, s1);
	getline(cin, s2);
	string s3 = s1 + s2;
	vector<char>v;
	for (int i = 0; i < s3.size(); i++) {
		//判断s3.at(i)是否在v中 不在就push进去
		if (find(v.begin(), v.end(), s3.at(i)) == v.end())
			v.push_back(s3.at(i));
	}
	//迭代器遍历打印v
	for (vector<char>::iterator it = v.begin(); it != v.end(); it++) {
		cout << *it;
	}
	return 0;
}