Sudoku.Sudoku.Main C# (CSharp) Method

        static void Main(string[] args)
        {
            if (args.Length < 1)
            {
                System.Console.WriteLine("Insert file input");
                Environment.Exit(0);
            }
            var input = args[0];

            // read input into memory
            var data = File.ReadAllText(input);

            var stopwatch = new Stopwatch();

            var result = new StringBuilder();

            // solve all sudokus
            stopwatch.Start();
            foreach (string line in data.Trim().Split('\n'))
            {
                var sudoku = FromString(line);
                sudoku = Solve(sudoku);
                result.Append(ToString(sudoku));
            }
            stopwatch.Stop();
            // write solutions to file
            var output = "solved_" + Path.GetFileName(input);
            File.WriteAllText(output, result.ToString());

            // present time result
            System.Console.WriteLine(" -- Elapsed time: {0} ms.", stopwatch.ElapsedMilliseconds);
        }