$(document).ready(function(e) {
	// add event listeners for mouse over and mouse out to swap images
	$("#nav-bar img").each(function(index, element) {
		$(this).mouseenter(function(e) {
			if ($(this).attr("class") != "selected")
			{
				var source = $(this).attr("src");
				var path = source.substring(0, source.lastIndexOf("/") + 1);
				var filename = source.substring(source.lastIndexOf("/") + 1);
				var name = filename.substring(0, filename.lastIndexOf("."));
				$(this).attr("src", path + name + "_over.gif");
			}
		});
		
		$(this).mouseleave(function(e) {
			if ($(this).attr("class") != "selected")
			{
				var source = $(this).attr("src");
				var path = source.substring(0, source.lastIndexOf("/") + 1);
				var filename = source.substring(source.lastIndexOf("/") + 1);
				var name = filename.substring(0, filename.lastIndexOf("_over.gif"));
				$(this).attr("src", path + name + ".gif");
			}
		});
	});
});