asd

using System;
using System.IO;

class Program
{
    static int RowsCount(int[,] matrix)
    {
        return matrix.GetUpperBound(0) + 1;
    }

    static int ColumnsCount(int[,] matrix)
    {
        return matrix.GetUpperBound(1) + 1;
    }

    static int[,] Read_Matrix(string name, StreamReader reader)
    {
        Console.Write("Количество строк матрицы {0}: ", name);
        int n = Convert.ToInt32(Console.ReadLine());
        Console.Write("Количество столбцов матрицы {0}: ", name);
        int m = Convert.ToInt32(Console.ReadLine());

        int[,] matrix = new int[n, m];
        for (int i = 0; i < n; i++)
        {
            string s = "";
            string tmp;
            int count = 0;

            while (true)
            {
                tmp = Convert.ToString(Convert.ToChar(reader.Read()));

                if (tmp == " ")
                {
                    if (s != "")
                    {
                        matrix[i, count] = Convert.ToInt32(s);
                        count++;
                    }
                    s = "";
                    continue;
                }
                if (tmp == "\n")
                {
                    if(s != "")
                        matrix[i, count] = Convert.ToInt32(s);
                    break;
                }

                s = s + tmp;
            }
        }

        return matrix;
    }

    static void Print_Matrix(int[,] matrix, StreamWriter writer)
    {
        for (int i = 0; i < RowsCount(matrix); i++)
        {
            for (int j = 0; j < ColumnsCount(matrix); j++)
                writer.Write(matrix[i, j].ToString().PadLeft(6));
            writer.WriteLine();
        }
    }

    static int[,] Matrix_Mult(int[,] matrixA, int[,] matrixB)
    {
        if (ColumnsCount(matrixA) != RowsCount(matrixB))
            throw new Exception("ERROR: Умножение не возможно.\n\tКоличество столбцов первой матрицы не равно количеству строк второй матрицы.");

        int[,] matrixC = new int[RowsCount(matrixA), ColumnsCount(matrixB)];

        for (int i = 0; i < RowsCount(matrixA); i++)
            for (int j = 0; j < ColumnsCount(matrixB); j++)
            {
                matrixC[i, j] = 0;
                for (int k = 0; k < ColumnsCount(matrixA); k++)
                    matrixC[i, j] += matrixA[i, k] * matrixB[k, j];
            }

        return matrixC;
    }

    static void Main(string[] args)
    {
        string input_file = "matrix.txt";
        string result_file = "result.txt";
        StreamReader reader = new StreamReader(input_file);
        StreamWriter writer = new StreamWriter(result_file, false);

        int[,] a = Read_Matrix("A", reader);
        //Print_Matrix(a, writer);
        reader.Read();
        int[,] b = Read_Matrix("B", reader);
        //Print_Matrix(b, writer);

        int[,] result = Matrix_Mult(a, b);
        Print_Matrix(result, writer);
        reader.Close();
        writer.Close();
    }
}