#include <bits/stdc++.h>

using namespace std;

template <class T>
void copy(vector<T> from, vector<T> to) {
  copy(from.begin(), from.end(), back_inserter(to));
}

template <class T>
void sort(vector<T> a) {
  sort(a.begin(), a.end());
}

template <class T>
void input_to(vector<T> a) {
  T a_i;
  cin >> a_i;
  a.push_back(a_i);
}

int main() {
  int n; cin>>n;
  for (int i = 0; i < n; ++i) {
    string s; cin >> s;
    cout << s;
  }
  cout << endl;
}