PHP Taskbook Level 8.4

When a user enters a page, record the user's login time in the session. After refreshing the page, display the user's last login time on the screen.

Given some URL:

php$url = 'http://test.com/dir1/dir2/dir3/page.html';

Get folders from it as an array:

php['dir1', 'dir2', 'dir3']

Display the following pyramid on the screen:

Given a list of cities and their countries, stored in the following structure:

php<?php
  $data = [
    [
      'country' => 'country1',
      'city' =>    'city11',
    ],
    [
      'country' => 'country2',
      'city' =>    'city21',
    ],
    [
      'country' => 'country3',
      'city' =>    'city31',
    ],
    [
      'country' => 'country1',
      'city' =>    'city12',
    ],
    [
      'country' => 'country1',
      'city' =>    'city13',
    ],
    [
      'country' => 'country2',
      'city' =>    'city22',
    ],
    [
      'country' => 'country3',
      'city' =>    'city31',
    ],
  ];
?>

Write code that will remake the data structure into this:

php[
  'country1': [
    'city11', 'city12', 'city13',
  ],
  'country2': [
    'city21', 'city22'
  ],
  'country3': [
    'city31', 'city32'
  ],
]