#!/usr/local/bin/perl

use strict;
use warnings;

my %category_hash =
  (
   1 => {
         name => 'whatever',
         children => {
           2 => {
                 name => 'something',
                 children => {
                   3 => { name => 'another subcategory' }
                 }
                }
          }
         },
    4 => { name => 'something else' }
  );