import java.util.Scanner;
public class slove{
	public static void main(String[] args){
		Scanner stdIn = new Scanner(System.in);
		int N = stdIn.nextInt();
		String out;
		StringBuffer sb = new StringBuffer();
		for(int i = 0; i < N; i++){
			String S = stdIn.next();
			sb.append(S);
		}
		out = sb.toString();
		System.out.println(out);
	}
}