- array_diff_assoc: documentation ( source)
- print_r: documentation ( source)
<?php
$a = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$b = array("a" => "green", "yellow", "red");
$c = array("c" => "blue");
print_r(array_diff_assoc($a, $b, $c));