php语法如何查询两个数组的交集元素

$animalA = array("cat", "dog", "pig", "panda");
$animalB = array("dog", "panda", "fish", "snake");
$commonAnimal = array_intersect($animalA, $animalB);
print_r($commonAnimal);

//输出结果：
Array (
  [1] => dog
  [3] => panda
)