#include<bits/stdc++.h>
using namespace std;
int main()
{
	string a,b;
	cin>>a>>b;
	string s=a+b;
	string s2="";
	int s3=s.size()-1;
	for(int i=0;i<=s3;i++)
	{
		if(s2.find(s[i])==-1)
		{
			s2+=s[i];
		}
	}
	int s4=s2.size();
	for(int i=0;i<s4;i++)
	{
		cout<<s2[i];
	}
	return 0;
}
/**************************************************************
	Problem: 1105
	User: wangyuxin
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2076 kb
****************************************************************/