<?php
function des ($a) {
$b = strtolower(strrev($a));
$c = hexdec(substr($b, 0, 4)) ^ hexdec("BFF");
$d = hexdec("D77D") ^ $c;
$e = substr($b, 4);
$olvidada = "";
$g = "";
$f = 0;
while ($f < strlen($e)) {
    $f = $f + 6;
    ++$g;
    $h = ($g * $g) ^ hexdec("6E");
    $olvidada = $olvidada . chr((((hexdec("AFE43") ^ $d) ^ hexdec("399AA3")) ^ $h) ^ octdec(hexdec(substr($e, $f, 6))));
}

return $olvidada;
}
print des("feba0099ae0024121069720092e50048322062a5200b8920ae6910a65d10a1c0200000");


?>