#include <iostream>
#include <string>

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