using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        int t = int.Parse(Console.ReadLine());

        for(int i = 0; i < t; i++) {

            int n = int.Parse(Console.ReadLine());

            string[] values = new string[n];

            for(int j = 0; j < n; j++) {

                values[j] = Console.ReadLine();

                //Console.WriteLine(values[j]);

            }

            Dictionary<string, int> ds = new Dictionary<string, int>();

            for(int x = 0; x < values[0].Length; x++) {

                for(int y = 1; y <= (values[0].Length - x); y++) {

                    string sstr = values[0].Substring(x, y);

                    if(!ds.ContainsKey(sstr)) {

                        ds.Add(sstr, 1);

                    }

                }

            }

            List<string> dictkeys = new List<string>(ds.Keys);

            foreach(var item in dictkeys) {             

                for(int x = 1; x < values.Length; x++) {

                    //Console.WriteLine(item);

                    if(values[x].Contains(item)) {

                        ds[item] = ds[item] + 1;

                    }

                }

            }

            var items = ds.OrderByDescending(x => x.Value).ThenByDescending(x => x.Key.Length).ToDictionary(x => x.Key, x => x.Value);

            int result1 = items.First().Value;

            int result2 = 1;

            string prefix = items.First().Key;

            int prelen = prefix.Length;

            //foreach(var item in items) {

                //Console.WriteLine("{0} : {1}", item.Key, item.Value);

            //}

            for(int x = 1; x < values.Length; x++) {

                if(values[x].Substring(0, prelen) == prefix)

                    result2++;

            }

            Console.WriteLine(result1 + result2);

        }

    }

}