using System;

public class Program

{

    public static void Main()

    {   

 Console.Write("Enter the number of rows: ");

            int N = int.Parse(Console.ReadLine());

            Console.Write("Enter the number of columns: ");

            int M = int.Parse(Console.ReadLine());

            int[,] a = new int[N, M];

            Random x = new Random();

            for (int r = 0; r < N; r++)

                for (int c = 0; c < M; c++)

                    a[r, c] = x.Next(10,100);

            for (int r = 0; r < N; r++)

            {

                for (int c = 0; c < M; c++)

                    Console.Write("{0,4}", a[r, c]);

                Console.WriteLine();

            }

            int min = a[0, 0];

            int max = a[0, 0];

            for (int r = 0; r < N; r++)

                for (int c = 0; c < M; c++)

                {

                    if (a[r, c] < min) min = a[r, c];

                    if (a[r, c] < max) max = a[r, c];

                }

            Console.WriteLine("The smallest value of an array element is: " + min);

            Console.WriteLine("The smallest value of an array element is: " + max);

            var k = x.Next(N);

            double S = 0;

                for (int c = 0; c < M; c++) S = S + a[k, c];

            Console.WriteLine("The sum of the elements of row {0} is: {1}", k, S);

            Console.WriteLine("The avarage of the elements of row {0} is: {1:F2}", k, S/M);

        }

    }

​