function viewMain(tab)
{
	var main = document.getElementById("main");
	var div;
	
	for (var i = 1; i < main.childNodes.length-1; i=i+2)
	{
		div = main.childNodes.item(i);
		if (div.id == "main_" + tab)
		{
			div.className = "show";
		} else
		{
			div.className = "hide";
		}
	}
}

function switchClass(id, class1, class2)
{
	var element = document.getElementById(id);
	
	if (element.className == class1)
	{
		element.className = class2;
	} else
	{
		element.className = class1;
	}
}
function showhide(id)
{
	 switchClass(id, 'show', 'hide');
}