#include <stdio.h>
#include <stdlib.h>

short main(void)
{
	short n;
	scanf("%hd", &n);
	char s[32][32];
	for (short i = 0; i < n; i++) scanf("%s", s[i]);
	for (short i = 0; i < n; i++) printf("%s", s[i]);
	printf("\n");
	return 0;
}