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

/**************************************************************
	Problem: 1105
	User: linmiaoling
	Language: C++
	Result: Accepted
	Time:20 ms
	Memory:2076 kb
****************************************************************/