package yukicoder.No597;

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		
		int N = in.nextInt();
		String ans = "";
		for (int i = 0; i < N; i++) {
			String S = in.next();
			ans += S;
		}
		System.out.println(ans);
	}
}