#include<bits/stdc++.h>
using namespace std;
int main(){
	string s1,s2,s3,s4;
	int c=0;
	getline(cin,s1);
	getline(cin,s2);	
	s3=s1+s2;
	for(int i=0;i<s3.size();i++){
		if(s4.find(s3[i])==-1) s4=s4+s3[i];
	}
	cout<<s4;

	return 0;
}

/**************************************************************
	Problem: 1105
	User: zhuanghaoxiang
	Language: C++
	Result: Accepted
	Time:10 ms
	Memory:2076 kb
****************************************************************/