x
 
<!DOCTYPE html>
<html>
<body>
<?php
$x = array("a" => "apple", "b" => "banana");  
$y = array("c" => "orange", "d" => "peach");  
$z = $x + $y; // $x 与 $y 的联合
var_dump($z);
echo "<br>";
var_dump($x == $y);
echo "<br>";
var_dump($x === $y);
echo "<br>";
var_dump($x != $y);
echo "<br>";
var_dump($x <> $y);
echo "<br>";
var_dump($x !== $y);
?>   
</body>
</html>