#include<iostream>
#include<algorithm>
#include<string.h>
using namespace std;
string s[25];
int main() {
	int n,k=0;
	cin >> n;
	for (int i = 0; i < n; i++) {
		std::cin >> s[i];
	}
	string max = "0", sum;
	for (int j = 0; j < n; j++) {
		for (int i = j+1; i < n; i++) {
			if (s[j] < s[i]) {
				swap(s[j], s[i]);
				//cout << "??";
			}
			if (s[j] == s[i]) {
				if (s[j][1] < s[i][1]) {
					swap(s[j], s[i]);
					
				}
				else if (s[j][1] == s[i][1]) {
					
						swap(s[j], s[i]);
					
				}
			}
			else continue;
		}
	}
	for (int i = 0; i < n; i++) {
		sum = sum + s[i];
		cout << sum<<endl;
	}
	cout << sum;
}