#include<bits/stdc++.h>
using namespace std;

int main(){
    string s1,s2,s3,s;
    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: hang
	Language: C++
	Result: Accepted
	Time:14 ms
	Memory:2076 kb
****************************************************************/