#include<bits/stdc++.h>
using namespace std;
int main(){
    string s,c1,c2,c3;
    cin>>c1>>c2;
    c3=c1+c2;
    for(int i=0;i<c3.size();i++){
        if(s.find(c3[i])==-1) s+=c3[i];
    }
    cout<<s;
    return 0;
}
/**************************************************************
	Problem: 1105
	User: huanghengyi
	Language: C++
	Result: Accepted
	Time:14 ms
	Memory:2076 kb
****************************************************************/