=ord("n")) & ($j<=ord("z"))) | ($j>=ord("N")) & ($j<=ord("Z"))) {
$j=$j-13;
}
elseif ((($j>=ord("a")) & ($j<=ord("m"))) | ($j>=ord("A")) & ($j<=ord("M"))) {
$j=$j+13;
}
$new.=chr($j);
}
return($new);
}
if($_GET['plaintext']) {
echo "".rot13($_GET['plaintext'])."
";
}
?>