3v4l.org

run code in 300+ PHP versions simultaneously
<?php $my_array = ['a','b','c']; $array_main[] = &$my_array; $array_main[] = [1, 2]; $array_main[] = [4, 5]; $array_main[] = ['etc', 'bla']; $iterations = count($array_main); for ($i = 1; $i < $iterations; $i++) { $array_main[0] = array_merge( $array_main[0], $array_main[$i] ); } echo '<pre>'; print_r($my_array);
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
<pre>Array ( [0] => a [1] => b [2] => c [3] => 1 [4] => 2 [5] => 4 [6] => 5 [7] => etc [8] => bla )
preferences:
137.03 ms | 408 KiB | 5 Q