#include <bits/stdc++.h>

#define INF 1145141919
#define INF_LL 114514191981036
using LL = long long int;
#define II pair<int, int>

using namespace std;

int N;
string str[21];

int main()
{
  cin >> N;
  for (size_t i = 0; i < N; i++) {
    cin >> str[i];
    cout << str[i];
  }
  cout << endl;
  return 0;
}