using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

​

namespace NMC2L2

{

    class Program

    {

        public const double A_const = 0.5 + 0.1 * 7;

        public const double L = 1;

        public const double N = 10, M = 10;

        public const double T = 1;

        public const double H = 1 / N;

        public const double Tau = T / M;

​

        public static double S_func => (Tau * Tau) / (H * H);

​

        public static double A_func(double x) => 1 / (1 + x);

        public static double A_func_2diff(double x) => 2 / Math.Pow(1 + x, 3);

        public static double B_func(double x) => -A_const / Math.Pow(1 + x, 2);

        public static double Y0_func(double t) => 1 / (A_const * t + 1);

        public static double Y1_func(double t) => 1 / (A_const * t + 2);

        public static double F_func(double x, double t) => 2 * (A_const * A_const- 1) / Math.Pow(x + A_const * t + 1, 3);

​

        public static double Get_x(double i) => H * i;

        public static double Get_t(double i) => Tau * i;

​

        public static void PrintMassive(double[,] mass, double[] t, double[] x)

        {

            Console.WriteLine(" t -  ");

            for (int i = 0; i <= mass.GetUpperBound(0); i++)

            {

                Console.Write("| {0,3:0.0} |",t[t.Length-1-i]);

                for (int j = 0; j <= mass.GetUpperBound(1); j++)

                {

                    Console.Write(" {0,5:0.000}", mass[i, j]);

                }

                Console.WriteLine();

            }

            Console.Write("  x -> |");

            for (int i = 0; i < x.Length; i++)

                Console.Write(" {0,3:0.0} |", x[i]);

        }

​

        static void Main(string[] args)

        {

            double[] x = new double[(int)N + 1];

            double[] t = new double[(int)N + 1];

            double[,] y = new double[(int)N + 1, (int)M + 1];

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

            {

                x[i] = Get_x(i);

                t[i] = Get_t(i);

                y[i, 0] = A_func(x[i]);

                y[i, 1] = A_func(x[i]) + Tau * B_func(x[i]) + ((Tau * Tau) / 2) * (A_func_2diff(x[i]) + F_func(x[i], 0));

                y[0, i] = Y0_func(Get_t(i));

                y[(int)N, i] = Y1_func(t[i]);

            }

            for (int j = 1; j < N; j++)

                for (int i= 1; i < M; i++) 

                {

                    y[i, j + 1] = S_func * y[i + 1, j] + 2 * (1 - S_func) * y[i, j] + S_func * y[i - 1, j] - y[i, j - 1] + Tau * Tau * F_func(Get_x(i), Get_t(j));

                }

            y = Transpose(y);

            PrintMassive(y,t,x);

        }

        public static double[,] Transpose(double[,] m)

        {

            int N = m.GetUpperBound(0);

            int M = m.GetUpperBound(1);

            double[,] t = new double[M + 1, N + 1];

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

            {

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

                {

                    t[i, j] = m[j, M - i];

                }

            }

            return t;

        }

    }

}

​