#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: chenmingyu
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2076 kb
****************************************************************/