using System;

using System.IO;

public class Program

{

    public static void Main()

    {

        //this section checks to see if a file name was included on the command line.

        if ( args.Length <= 0 )

        {

            Console.WriteLine("\n You need to include a filename.");

        }

        else 

        {

            //this section is for declaring objects for connecting to files...

            StreamReader InFile = null;

            StreamWriter OutFile = null;

            try

            {

                //opens file name included on commend line...

                InFile = File.OpenText(args[0]);

                //Creating the output file...

                OutFile = File.CreateText("outfile.txt");

                Console.Write("\nNumbering...");

                //Read first line of the file...

                string line = InFile.ReadLine();

                //loop through the file as long as not at the end...

                while (line != null)

                {

                    OutFile.WriteLine("{0}: {1}", ctr.ToString().PadLeft(3,'0'), line);

                    Console.Write("...{0}...", ctr.ToString());

                }

            }

            catch (System.IO.FileNotFoundException)

            {

                Console.WriteLine("Could not find the file {0}", args[0]);

            }

            catch (Exception e)

            {

                Console.WriteLine("Error: {0}", e.Message);

            }

            finally 

            {

                if (InFile != null)

                {

                    //Closing all files...

                    InFile.Close();

                    OutFile.Close();

                    Console.WriteLine("...Done.");

                }

            }

        }

    }

}