use system script advertising in wordpress multisite

by

I have write :

<?php
    $blog_id = get_current_blog_id();
?>
<?php if( 1 == $blog_id ); ?>
    <div id=""><script src=""></script><script src="" ></script></div>
<?php elseif( 2 == $blog_id ): ?>
    <div id=""><script src=""></script><script src="" ></script></div>
<?php else: ?>
    Default script
<?php endif; ?>

It correct !?