static void Main(string[] args)
{
Console.WriteLine("Making root entries...");
var root = new Directory("root");
var dir1 = new Directory("dir1");
var dir2 = new Directory("dir2");
var dir3 = new Directory("dir3");
var file1 = new File("file1");
var file2 = new File("file2");
var file3 = new File("file3");
var file4 = new File("file4");
root.AddEntry(dir1);
root.AddEntry(dir2);
dir2.AddEntry(dir3);
root.AddEntry(file1);
root.AddEntry(file2);
dir2.AddEntry(file3);
dir3.AddEntry(file4);
root.Output(0);
}