3v4l.org

run code in 300+ PHP versions simultaneously
<?php $t = array('a' => array(1,2,3)); $t2 = array('a' => array(3,6,7)); $t = array_combine(array_merge(array_keys($t), array_keys($t2) ), array_merge(array_values($t), array_values($t2) ) ); print_r($t);

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48.17 ms | 402 KiB | 5 Q