Exclude Parent category ids from array of category id's

Question

Hi i'm having a product collection, i'm getting those categories by $item->getCategoryIds();

On print_r($categoryIds = $item->getCategoryIds()); i'm getting

    Array
(
    [0] => 12
    [1] => 26
)
Array
(
    [0] => 22
    [1] => 26
)
Array
(
    [0] => 12
    [1] => 26
)
Array
(
    [0] => 12
    [1] => 26
)

In these category id 12 is parent for categories 26,22

So is there any way to exclude parent category i.e 12 from array ? Smething like this i'm looking for

    Array
(
    [0] => 26
)
Array
(
    [0] => 22
    [1] => 26
)
Array
(
    [0] => 26
)
Array
(
    [0] => 26
)

Answer 1

The easiest way is to not add the product to both categories, maybe make 12 a anchor category.

if you don't want this, you can load all the categories and check against $category->getPath() to filter parents...