DirectoryTraversal

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;


namespace DirectoryTransversal
{
    class Program
    {
        static void PrintDictionary (Dictionary<string, Dictionary<string, double>> fileCollection)
        {
            foreach(var extension in fileCollection)
            {
                Console.WriteLine(extension.Key);
                foreach(var pair in extension.Value)
                {
                    Console.WriteLine("file name: {0} - file size {1}", pair.Key, pair.Value);
                }
            }
        }
        static void Main()
        {
            Dictionary<string, Dictionary<string, double>> fileCollection = new Dictionary<string, Dictionary<string, double>>();
            string directory = @"../../";
            DirectoryInfo dirFiles = new DirectoryInfo(directory);
            foreach(FileInfo file in dirFiles.GetFiles())
            {
                string extension = file.Extension.ToString();
                string name = file.Name.ToString();
                double size = file.Length;
                if (!fileCollection.ContainsKey(extension))
                {
                    fileCollection[extension] = new Dictionary<string, double>();
                }
                fileCollection[extension].Add(name, size);
            }
            PrintDictionary(fileCollection);

            var sortedFiles = fileCollection.OrderByDescending(x => x.Value.Keys.Count).ThenBy(k => k.Value.Values);

            StreamWriter outputStream = new StreamWriter(string.Format("{0}log.txt", directory));
            using (outputStream)
            {
                foreach (var pair in sortedFiles)
                {
                    outputStream.WriteLine(pair.Key.ToString());
                    foreach (var file in pair.Value)
                    {
                        outputStream.WriteLine("file name: {0} - file size {1}", pair.Key, pair.Value);
                    }
                }
            }



        }
    }
}