Adsense code in variable

[minusp]

hello

can anyone help me on this script?
this is my script

<script type="text/javascript">
<!--
function fc() {
        var tt = '
<script type="text/javascript"><!--
google_ad_client = "pub-2606800903002383";
/* Download Butt 234x60, created 5/14/09 */
google_ad_slot = "0574420856";
google_ad_width = 234;
google_ad_height = 60;
//-->
</script>
<script type="text/javascript"
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
';
        document.getElementById("dl").innerHTML = tt;    
}

//-->
</script>


    <div id="dl">&nbsp;<h3 style="font-size: 24pt;" id="zeit">dd</h3></div>
    
        <script type="text/javascript">
        <!--
            fc();
        //-->
        </script>

in a part of my script I want to add google adsense code in "tt" variable
but I get error when I add the google code into that .
I think //--> in the google code makes problem.
can you add the adsense code in the tt variable without any error?
please help me.

Regards