#include <bits/stdc++.h>
using namespace std;
string b,c;
void mm(string in,string after)
{
	if(in.size()>0)
	{
		char ch=after[after.length()-1];
		cout <<ch;//为什么在这里直接输出（cout<<after[after.length()-1]）不对
		int k=in.find(ch);
		mm(in.substr(0,k),after.substr(0,k));
		mm(in.substr(k+1),after.substr(k,in.length()-k-1));
	}
}
int main()
{
	cin>>b;
	cin>>c;
	mm(b,c);
	return 0;
}