#include "bits/stdc++.h"

using namespace std;
using ll = long long;
using IP = pair<int, int>;

const ll INF = 1LL << 62;
#define atcoder(int)1e9+7
#define Endl endl
#define mp make_pair
#define all(v) v.begin(),v.end()
#define pb push_back

ll gcd(ll a, ll b) {//最大公約数
	if (a%b == 0)return b;
	else gcd(b, a%b);
}

ll lcm(ll a, ll b) {//最小公倍数
	return (a / gcd(a, b))*b;
}

int main(){

	int n;
	string s[20];

	cin >> n;

	for (int i = 0; i < n; i++) {
		cin >> s[i];
	}

	for (int i = 0; i < n; i++) {
		cout << s[i];
	}
	cout << endl;

	return 0;
}