import java.util.*;
import java.io.*;

public class Main{
    public static void main(String[] args){
        Main m = new Main();
        m.input();
        m.out();
    }

    int n;
    String s;
    public void input(){
        Scanner sc = new Scanner(System.in);
        n = sc.nextInt();
        s = sc.next();
        for(int i = 0; i < n - 1; i++){
            s = s + sc.next();
        }
        sc.close();
    }

    public void out(){
        System.out.println(s);
    }

}