static void Main(string[] args) { const string LogFile = "log.txt"; LogFileWriter logWriter = new LogFileWriter(LogFile); if (logWriter.LogFile == null)//throw exception { Console.WriteLine("LogFile doesn't exist or is readOnly!"); } Console.WriteLine("Choose type of equation you want to solve: 'L' - linear, 'Q' - quadratic\n" + "or any other key to exit and press 'Enter':"); Equation equation = ChooseEquationType(Console.ReadLine().ToUpper(), logWriter); if (equation != null) { string result = equation.GetEquationAndSolutionRecord(); Console.WriteLine(result); logWriter.WriteEquationToLog(result); } string fileNameWithMatrix = ConfigurationManager.AppSettings["fileNameWithMatrix"]; MatrixReader matrixReader = new MatrixReader(fileNameWithMatrix); double[,] matrix1 = matrixReader.GetMatrix(); double[,] matrix2 = matrixReader.GetMatrix(); Console.WriteLine(MatrixCalculator.GetMultiplicationStringResult(matrix1, matrix2)); Console.ReadKey(); }