PHP Taskbook Level 8.3

Given some URL:

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

Get the protocol from it:

php'http';

The following array is given:

php<?php
  $arr = [1, 2, 3, 4, 5, 6];
?>

The number is also given:

php<?php
  $num = 3;
?>

Add as many empty strings to the given array as necessary so that the length of the array becomes equal to the square of the number from the variable.

Display the following pyramid on the screen: