/*
 *No.597 1st            failed
 */
#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;
int main(void)
{
	int n;   char str[201];
	str[0]='\0';
	cin>>n;
	for (int i=0;i<n;i++){
		char s[21];
		cin>>s;
		sprintf(str,"%s%s",str,s);
	}
	cout<<str;
}