static void Main() { string path = @"C:\Windows"; FolderTree windowsTree = new FolderTree(path); windowsTree = windowsTree.TreeDFS(); Folder appPatch = windowsTree.FindFolder(@"C:\Windows\AppPatch"); double sum = appPatch.CalculateFileSizeSum(appPatch) / 1048576; Console.WriteLine(@"sum of files in C:\Windows\AppPatch = {0:0.00}mb", sum); }