Program

using System;

namespace ConsoleApp3
{
    class Program
    {
        static void Main(string[] args)
        {
            Random rand = new Random();
            int i, j, Enew = 0, Eold = 0;
            int n = 5;
            int[,] mass = new int[n, n];
            double P, T, M, ET;


            for (i = 0; i < n; i++)
            {
                for (j = 0; j < n; j++)
                {
                    mass[i, j] = rand.Next(0, 2);
                    if (mass[i, j] == 0)
                    {
                        mass[i, j] = -1;
                    }
                    //Console.Write("{0}\t", mass[i, j]);
                }
                //Console.WriteLine();
            }

            while(true)
            {
                var start = System.Diagnostics.Stopwatch.StartNew();

                for (i = 0; i < n; i++)
                {
                    for (j = 0; j < n; j++)
                    {
                        mass[i, j] = rand.Next(0, 2);
                        if (mass[i, j] == 0)
                        {
                            mass[i, j] = -1;
                        }
                        //Console.Write("{0}\t", mass[i, j]);
                    }
                    //Console.WriteLine();
                }
                T = 0.01;
                Console.WriteLine("--------------------------------------");
                Console.WriteLine("--------------------------------------");
                for (i = 0; i < n; i++)
                {
                    for (j = 0; j < n; j++)
                    {
                        Console.Write("{0}\t", mass[i, j]);
                    }
                    Console.WriteLine();
                }

                for (int k = 0; k < 1000000; k++)
                {
                    i = rand.Next(0, n);
                    j = rand.Next(0, n);
                    Eold = Energy(i, j, mass, n);
                    mass[i, j] *= -1;
                    Enew = Energy(i, j, mass, n);
                    if (Eold < Enew)
                    {
                        P = Math.Pow(2.718, -(Enew - Eold) / T);
                        if (P < rand.NextDouble())
                        {
                            mass[i, j] *= -1;
                        }
                    }
                }


                Console.WriteLine("--------------------------------------");
                for (i = 0; i < n; i++)
                {
                    for (j = 0; j < n; j++)
                    {
                        Console.Write("{0}\t", mass[i, j]);
                    }
                    Console.WriteLine();
                }


                M = Magnetic(mass, n);
                ET = TotalEnergy(mass, n);
                //save E M
                Console.Write(T);
                Console.Write(" ");
                Console.Write(Eold);
                Console.Write(" ");
                Console.Write(ET);
                Console.Write(" ");
                Console.WriteLine(M);

                start.Stop();
                Console.WriteLine(start.ElapsedMilliseconds);

                //Eold = Energy(1, 1, mass, n);
                //Console.WriteLine(Eold);

            }
            Console.ReadKey();




        }

        static int Energy(int i, int j, int[,] mass, int n)
        {
            int E = 0;
            E += mass[i, j] * mass[(i + 1) % n, j];
            E += mass[i, j] * mass[(n + i - 1) % n, j];
            E += mass[i, j] * mass[i, (j + 1) % n];
            E += mass[i, j] * mass[i, (n + j - 1) % n];
            return -E;
        }

        static double Magnetic(int [,] mass, int n)
        {
            double M = 0;
            for (int i = 0; i < n; i++)
            {
                for(int j = 0; j < n; j++)
                {
                    M += mass[i, j];
                }
            }
            M /= (n * n);
            return M;
        }

        static double TotalEnergy(int[,] mass, int n)
        {
            int E = 0;
            double Summ = 0;
            for (int k = 0; k < n; k++)
            {
                for (int t = 0; t < n; t++)
                {
                    E = Energy(k, t, mass, n);
                    Summ += E;
                }
            }

            Summ /= (n * n);
            Summ /= 2;
            return Summ;
        }
    }
}