// In the name of God
// Code by: overfloW

#include <bits/stdc++.h>

using namespace std;

const int MN = 100+100;

string s,t;

int dp[MN][MN];
char c[MN][MN];
int q[MN][MN];

string res;

vector<int>v,u;
vector<string>R;

void reset()
{
	for(int i=0;i<MN;++i)
		for(int j=0;j<MN;++j){
			dp[i][j] = 0;
			q[i][j] = 0;
			c[i][j] = 0;
		}
	v.clear(), u.clear();
	res.clear();
}

void solve()
{
	reset();
	s = ' ' + s;
	t = ' ' + t;
	for(int i=1;i<s.size();++i)
		for(int j=1;j<t.size();++j){
			if(t[j] == s[i])
				q[i][j] = i;
			else
				q[i][j] = q[i-1][j];
		}
	for(int i=1;i<s.size();++i)
		for(int j=1;j<t.size();++j){
			if(dp[i][j-1] <= dp[q[i][j]-1][j-1] + 1){
				dp[i][j] = dp[q[i][j]-1][j-1] + 1;
				c[i][j] = t[j];
			}
			else{
				dp[i][j] = dp[i][j-1];
				c[i][j] = c[i][j-1];
			}
		}
//
	int counter2 = t.size()-1;
	int counter1 = s.size()-1;
	while(counter2 >= 0){
		if(c[counter1][counter2] == s[q[counter1][counter2]]){
			v.push_back(q[counter1][counter2]);
			u.push_back(counter2);
			counter1 = q[counter1][counter2] - 1;
			--counter2;
		}		
		else{
			--counter2;
		} 
	}
	for(int i=0;i<v.size()/2;++i){
		swap(v[i] , v[v.size()-i-1]);
		swap(u[i] , u[u.size()-i-1]);
	}
		
//
	counter1 = 1 , counter2 = 1;
	int current = 0;
	while(current < v.size()){
		if(counter1 != v[current]){
			res += s[counter1];
			++counter1;
		}else if(counter2 != u[current]){
			res += t[counter2];
			++counter2;
		}
		else{
			res += s[counter1];
			++counter1 , ++counter2 , ++current;
		}
	}	
//
	if(counter1 < s.size())
		for(int i=counter1;i<s.size();++i)
			res += s[i];
	if(counter2 < t.size())
		for(int i=counter2;i<t.size();++i)
			res += t[i];
	cout << res << endl;
}

void input_Cases()
{
	while(cin >> s >> t)
		solve();
	for(int i=0;i<R.size();++i)
		cout << R[i] << endl;
}

int main()
{
	input_Cases();
	return 0;
}