/**
* Gets the advert JavaScript to display a DoubleClick advert.
*
* @param  adSite        The name of the site (DART Site)
* @param  area          The DART Area
* @param  size          The size of the advert
* @param  tile          The tile value for the advert (must be unique on the page and represents the order the advert appears)
* @param  dcopt         Set to true for intistitial adverts (e.g. top banner) 
*/
function GetAd(adSite, area, size, tile, dcopt) {
    ord = window.ord || Math.floor(Math.random() * 1E16);

    document.write('<script type="text/javascript" src="http://ad.uk.doubleclick.net/adj/');
    document.write(adSite + '/' + area + ';');
    document.write('area=' + area + ';');
    document.write('tile=' + tile + ';');

    if (dcopt == true) {
        document.write('dcopt=ist;');
    }

    document.write('sz=' + size + ';');
    document.write('ord=' + ord + '?"><\/script>');
}