matrix example

using System;
using System.Collections.Generic;
using System.Linq;


    class Program
    {
        static void Main()
        {
             // tuk priemame kolko ste e golqma matricata neinite razmeri i si inicializirame nujnite promenlivi

            int[] input = Console.ReadLine().Split().Select(int.Parse).ToArray();
            int n = input[0];
            int m = input[1];
            int[,]matrix=new int[n,m];
            List<int> result= new List<int>();

            // matricata e gotova no trqbwa da q napulnim s nqkakvi chisla ako davat gotova matrica tova e izlishno!
            for (int k = 0; k <n ; k++)
            {
                int[] numbers = Console.ReadLine().Split().Select(int.Parse).ToArray();
                for (int i = 0; i < m; i++)
                {
                    matrix[k, i] = numbers[i];

                }

            }


           // proverka na chislata w matricata
            for (int i = 0; i < n; i++)
            {

            int medium = 0;
            for (int j = 0; j < m; j++)
            {
             bool Istrue = matrix[i, j] >= 100 && matrix[i, j] <= 1000;

                if (Istrue)
                if (j == i)
                    {
                        medium += matrix[i, j];
                    }
            }
                result.Add(medium);
        }
           Console.WriteLine(string.Join(" ",result));
        }

    }