array_intersect — Returns an array containing
elements that are present in all array arguments.
array array_intersect(array_1, array_2[, . .
array array_1: First array
array array_2: Second array
array . . . (optional):
Further arrays to intersect
Array on success; NULL on failure
This function accepts at least two arrays as arguments,
and returns an array containing all elements that appear
in all given array arguments. The keys of the resultant
array are those of the matching elements from the first
PHP 4 since 4.0.1
Example 20. Calculate the
intersection of three arrays
$array_1 = array('brown bat', 'fruit bat', 'wombat', 'baseball bat');
$array_2 = array('goatsucker', 'wombat', 'mongoose', 'mon ami');
$array_3 = array('wombat', 'goatsucker', 'mongoose', 'baseball bat');
$intersection = array_intersect($array_1, $array_2, $array_3);
/* Expected output:
*  => wombat
* Note that the key is '2', which is the matching key from the first array.
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing
(Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch).
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