Add embedded code in custom layout

gistfile1.txt

<?php

$uri = ltrim( $_SERVER['REQUEST_URI'], '/' ); // Removes the leading slash.
$uri = rtrim( $uri, '/' ); // Removes the trailing slash.

$uri = str_replace('/', ' ', $uri); // Replaces the slashes with spaces.
?>
<script type="text/javascript" src="a.remarketstats.com/px/smart/?c=222ccaf40d04fb6&seg=<?php echo $uri; ?>" ></script>