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<?php $arr = array( array("item_data"=>array(1,2,3)), array("item_data"=>array(4,5,6)), array("item_data"=>array(7,8,9)) ); function merge($prev, $now) { return array_merge($prev, $now['item_data']); } $res = array_reduce($arr, "merge"); print_r($res);

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40.08 ms | 402 KiB | 5 Q