#include<bits/stdc++.h>
using namespace std;
int main(){
    string s1,s2,s3,s4;
    cin>>s1>>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: chenyaohuo
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2076 kb
****************************************************************/