public static void Main()
        {
            StreamReader inpFile = new StreamReader("input.txt");
            StreamWriter outpFile = new StreamWriter("output.txt");
            string nString = inpFile.ReadLine();
            int N = int.Parse(nString);
            int Ans = 0;

            List<List<int>> field = new List<List<int>>();
            for (int i = 0; i < N; i++)
            {
                List<int> row = new List<int>();
                foreach (var numb in inpFile.ReadLine().Split(' '))
                    row.Add(int.Parse(numb));
                field.Add(row);
            }
            for (int i = 0; i < N; i++)
                for (int j = 0; j < N; j++)
                {
                    if (j != N - 1)
                        Ans = Math.Max(Ans, Math.Abs(field[i][j] - field[i][j + 1]));
                    if (i != N - 1)
                        Ans = Math.Max(Ans, Math.Abs(field[i][j] - field[i + 1][j]));

                }
            outpFile.Write(Ans);
            outpFile.Flush();