function countElementsByClass(){

var count = 0;
var o = document.getElementsByTagName("div");
for  (var i=0; i< o.length; i++ ){
    if (o[i].className == "albumcolumn")
        count ++;
}

var gh = document.getElementById("wrapper").offsetWidth;
		alert (gh);

d = document.getElementById('wrapper');
d.style.width= count * 1000 + "px";

//var bh = document.getElementById("wrapper").offsetWidth;
	//	alert (bh);
//alert("Wrapper: " + document.getElementById("wrapper").style.Width);//You get your Div number here;)
}