Simple implementation with nestedSortable plugin.

• Set database config in appliaction/config/database.php
• Set encryption_key in application/config/config.php
• Autoload database, session, url and form in application/config/autoload.php
• Import database.sql file to your database

You're ready to go - http://localhost/your_project/index.php/al

Starting with CodeIgniter 3.0, all class filenames (libraries, drivers, controllers and models) must be named in a Ucfirst-like manner or in other words - they must start with a capital letter. So, you have to rename following files:

controllers/al.php              => controllers/Al.php
models/adjacency_list_model.php => models/Adjacency_list_model.php
libraries/adjacency_list.php    => libraries/Adjacency_list.php