Wordpress post_category

Hello,

I want to add more than one term_id like

$articleOption['post_category'] = array(1,2,3,4,5);

there is an array like

$arr[0] = "0";
$arr[1] = "1";
$arr[2] = "2";

Code (markup):

although the $category output is like 1,2,3, it doesnt work

$category = implode(",", $arr);
$articleOption['post_category'] = array($category);

Code (markup):

However it works;

$cnt = count($arr);

if($cnt=1)
	$articleOption['post_category'] = array($arr[0]);
if($cnt=2)
	$articleOption['post_category'] = array($arr[0],$arr[1]);
if($cnt=3)
	$articleOption['post_category'] = array($arr[0],$arr[1],$arr[2]);
if($cnt=4)
	$articleOption['post_category'] = array($arr[0],$arr[1],$arr[2],$arr[3]);
if($cnt=5)
	$articleOption['post_category'] = array($arr[0],$arr[1],$arr[2],$arr[3],$arr[4]);
if($cnt=6)
	$articleOption['post_category'] = array($arr[0],$arr[1],$arr[2],$arr[3],$arr[4],$arr[5]);

Code (markup):

So I think it just accept integer one by one.
How can I get rid of these if conditions ?
please help me

thanks..