3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = array( 0 => array( '1' => '123', '2' => '120', '3' => '30', '4' => '150' ), 1 => array( '1' => '123', '2' => '122', '3' => '30', '4' => '158' ), 2 => array( '1' => '123', '2' => '129', '3' => '300', '4' => '150' ) ); $a = array_merge(...$array); print_r($a); echo max($a);
Output for 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 - 8.1.29, 8.2.0 - 8.2.20, 8.3.0 - 8.3.8
Array ( [0] => 123 [1] => 120 [2] => 30 [3] => 150 [4] => 123 [5] => 122 [6] => 30 [7] => 158 [8] => 123 [9] => 129 [10] => 300 [11] => 150 ) 300

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132.89 ms | 403 KiB | 185 Q