średnia ar

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    public class Program
    {
        public static void Main(string[] args)
        {
            //Your code goes here

            double[,] tablica = {
                {1 ,2 ,3},
                {4 ,5 ,6},
                {7, 8, 1}
            };

            Console.WriteLine("Najnizsza srednia: {0}", Average(tablica));
        }

        public static double Average(double[,] tablica)
        {
            int liczbaWierszy = tablica.GetLength(0);
            int liczbaKolumn = tablica.GetLength(1);

            double[] sumaKolumn = new double[liczbaKolumn];
            for (int w = 0; w < liczbaWierszy; w++)
            {
                for (int k = 0; k < liczbaKolumn; k++)
                {
                    sumaKolumn[k] += tablica[w, k];
                }
            }
            for (int i = 0; i < liczbaKolumn; i++)
            {
                sumaKolumn[i] = sumaKolumn[i] / liczbaWierszy;
            }
            return sumaKolumn.Min();
        }
    }
}