3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr1 = array(1, 2, 3, 4); $arr2 = array("a" => array(1, 2, 3)); $arr3 = array(); print_r(array_merge_recursive($arr1, $arr2));

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30.64 ms | 402 KiB | 5 Q