PHP Decode

<?php 
/* by seo xbwseo.com */ 
global $; 
if (!function_exists('s')) { 
    function s($a) 
    { 
        return pack("H*", strrev($a)); 
    } 
} 
if (!function_exists('s')) { 
    function s($k, $i) 
    { 
        global $; 
        return $[$k][$i]; 
    } 
} 
if (!function_exists('sf')) { 
    function sf($k, $i) 
    { 
        global $; 
        $args = array_slice(func_get_args(), 2); 
        return call_user_func_array($[$k][$i], $args); 
    } 
} 
$['?] = array("56e696665646", "7455245444f5050514", false, "45f4f425f5050514", "563616c6075627f5274737", "c5", "f2", "56d616e6279646", "078607e2f65637772687f2f65637772687f25627f636"); 
foreach ($['?] as $___k => $___vo) { 
    gettype($['?][$___k]) == 'string' && ($['?][$___k] = s($___vo)); 
} 
$['?][0](s('?, 1), s('?, 2)); 
$['?][0](s('?, 3), $['?][4](s('?, 5), s('?, 6), $['?][7](__FILE__)) . s('?, 6)); 
require APP_ROOT . s('?, 8); ?>