#include <bits/stdc++.h>
using namespace std;

int main() {
	int n;
	cin >> n;
	string s[n];
	for (auto &i : s) {
		cin >> i;
	}
	string t = "";
	for (auto &i : s) {
		t += i;
	}
	cout << t << endl;
	return 0;
}