简单正则问题

[u013103952]

<?php
$str = '[div]a[div]c[/div][/div]';
preg_match_all("/\[div.*](.*)?\[\/div]/isU", $str, $block_arr, PREG_SET_ORDER);
print_r($block_arr);

?>

运行结果

Array
(
    [0] => Array
        (
            [0] => [div]a[div]c[/div]
            [1] => a[div]c
        )

)

期望结果：

Array
(
    [0] => Array
        (
            [0] => [div]a[div]c[/div][/div]
            [1] => a[div]c[/div]
        )
    [1] => Array
        (
            [0] => [div]c[/div]
            [1] => c
        )

)

请问怎么修改正则？谢谢

[xuzuning]

$str = '[div]a[div]c[/div][/div]';
$p = "/\[div[^]]*\]([^[\]]|((?R))*)\[\/div\]/is";

preg_match_all($p, $str, $block_arr);
print_r($block_arr);

Array ( [0] => Array ( [0] => [div]c[/div] ) [1] => Array ( [0] => c ) [2] => Array ( [0] => ) )