bestSumBestRowBestColl

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MaxPlatform2x2
{
    class bestSumBestRowBestColl
    {
        static void Main(string[] args)
        {
            string[] rowsColls = Console.ReadLine().Split(' ');
            int[] rowsCollsInt = rowsColls.Select(int.Parse).ToArray();
            int[,] matrix = new int[rowsCollsInt[0], rowsCollsInt[1]];
            for (int i = 0; i < rowsCollsInt[0]; i++)
            {
                string[] input = Console.ReadLine().Split(' ');
                for (int j = 0; j < rowsCollsInt[1]; j++)
                {
                    matrix[i, j] = int.Parse(input[j]);
                }
            }

            int bestSum = int.MinValue;
            int bestRow = 0;
            int bestColl = 0;
            for (int i = 0; i < matrix.GetLength(0) - 2; i++)
            {
                for (int j = 0; j < matrix.GetLength(1) - 2; j++)
                {
                    int sum = matrix[i, j] + matrix[i, j + 1] + matrix[i, j + 2] + matrix[i + 1, j] + matrix[i + 1, j + 1] + matrix[i + 1, j + 2] + matrix[i + 2, j] + matrix[i + 2, j + 1] + matrix[i + 2, j + 2];
                    if (sum > bestSum)
                        bestSum = sum;
                    {
                        bestRow = i;
                        bestColl = j;
                    }
                }
            }
            Console.WriteLine("best matc:");
            Console.WriteLine("{0} {1} {2}", matrix[bestRow, bestColl - 1], matrix[bestRow, bestColl], matrix[bestRow, bestColl + 1]);
            Console.WriteLine("{0} {1} {2}", matrix[bestRow + 1, bestColl - 1], matrix[bestRow + 1, bestColl], matrix[bestRow + 1, bestColl + 1]);
            Console.WriteLine("{0} {1} {2}", matrix[bestRow + 2, bestColl - 1], matrix[bestRow + 2, bestColl], matrix[bestRow + 2, bestColl + 1]);
            Console.WriteLine("Sum = {0}", bestSum);
        }
    }
}