cc1

using System;
using System.Collections.Generic;
using System.IO;

namespace CodeCup
{
    class Program
    {
        static bool Check(string[][] x)
        {
            var result = false;

            foreach (var i in x)
            {
                foreach (var i2 in i)
                {
                    if (i2 == "0")
                        result = true;
                }
            }

            int n = x.Length;

            for (int j = 0; j < n -1; j++ )
                for (int j2 = 0; j2 < n - 1; j2++)
                {
                    if (
                        x[j][j2] == x[j+1][j2]
                        ||
                        x[j][j2] == x[j ][j2 + 1]


                        )
                    {
                        result = true;
                    }
                }


                return result;
        }

        static void Main(string[] args)
        {
            string filename;

            if (args.Length > 0 )
                filename = args[0];

            // закомментить
            filename = "input.txt";
            string outputFilename = filename + ".a";

            int t;
            int n;
            List<string> answers = new List<string>();


            using (StreamReader reader = new StreamReader(filename))
            {
                string line;

                line = reader.ReadLine();
                t = int.Parse(line);

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

                    line = reader.ReadLine();
                    n = int.Parse(line);
                    string[][] x = new string [n][];

                    for (int i2 = 0; i2 < n; i2++)
                    {
                        line = reader.ReadLine();
                        x[i2] = line.Split(new Char[] {' '});
                        //Console.WriteLine(string.Join(",", x[i2]));
                    }

                    answers.Add(Check(x) ? "YES" : "NO");
                    //Console.WriteLine(Check(x) ? "YES" : "NO");
                }


            }

            File.WriteAllLines(outputFilename, answers);

        }
    }
}