csharp

csharp

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            TextReader myfile = File.OpenText("file1.txt");
            TextWriter newfile = File.CreateText("output1.txt");
            string output = String.Concat(myfile.ReadToEnd().Reverse());
            newfile.Write(output);
            Console.WriteLine(output);
           

            TextReader myfile2 = File.OpenText("file2.txt");
            string line;
            while((line = myfile2.ReadLine()) != null)
            {
                if(line.Contains("void"))
                {
                    Console.WriteLine(line);
                }
            }

            TextReader myfile3 = File.OpenText("file3.txt");
            TextWriter newfile3 = File.CreateText("output3.txt");
            int i = 1;
            while ((line = myfile3.ReadLine()) != null)
            {
                newfile3.WriteLine("{0:D5}{1}", i, " " + line);
                Console.WriteLine(String.Format("{0:D5}{1}", i, " " + line));
                i++;
            }

            newfile3.Close();
            TextReader myfile4 = File.OpenText("output3.txt");
            TextWriter newfile4 = File.CreateText("output4.txt");

            while ((line = myfile4.ReadLine()) != null)
            {
                List<string> lineS = line.Split(' ').ToList();
                lineS.RemoveAt(0);
                string newStr = string.Join(" ", lineS.ToArray());
                newfile4.WriteLine(newStr);
                Console.WriteLine(newStr);
            }


            TextReader myfile5 = File.OpenText("file4.txt");
            TextWriter newfile5 = File.CreateText("output5.txt");


            Dictionary<string, int> lines = new Dictionary<string, int>();

            while ((line = myfile5.ReadLine()) != null)
            {
                
                string sline = line.Substring(23);
                string[] numbersS = sline.Split(' ');
                int[] numbers = new int[numbersS.Length];
                for(int k = 0; k < numbersS.Length; k++)
                {
                    try {
                        numbers[k] = int.Parse(numbersS[k]);
                    }
                    catch(Exception e)
                    {

                    }
                }
                line += "   " + numbers.Sum();
                lines.Add(line, numbers.Sum());
                newfile5.WriteLine(line);
                Console.WriteLine(line);
            }

            var sortedDict = from entry in lines orderby entry.Value ascending select entry;

            int pos = 0;
            int lastVal = -1;
            foreach (KeyValuePair<string, int> entry in sortedDict)
            {
                if(lastVal != entry.Value)
                {
                    pos++;
                }
                Console.WriteLine("Position " + pos + "    " + entry.Key);
            }



            Console.Read();


        }
    }   
}

May I know what is this program doing?