#include <iostream>
#include <string>
#include <fstream>
using namespace std;

#define in cin
//ifstream in("3280.txt");

bool inArray(string pals[], const string &pal, int n, int pos) {
	int len = pal.length();
	for (int i = 0; i < n; i++)
	{
		if (i != pos && pals[i].substr(0, len) == pal)
		{
			return true;
		}
	}
	return false;
}

int main()
{
	int n, escen = 1;
	while (in >> n && n != 0)
	{
		cout << escen++ << endl;
		string pals[n], pal;
		for (int i = 0; i < n; i++)
		{
			in >> pals[i];
		}
		for (int i = 0; i < n; i++)
		{
			int len = pals[i].length();
			for (int j = 1; j <= len; j++)
			{
				string substr = pals[i].substr(0, j);
				if (j == len || !inArray(pals, substr, n, i))
				{
					cout << pals[i] << " " << substr << endl;
					break;
				}
			}
		}
	}
	return 0;
}