var id_target = 'switcher';
var class_stub = 'new_';
var time_interval = 5000;
var size = 3;
var currentPic = 1;

advance = function(){
	
	//alert("hello");
	
	if(window.currentPic != window.size){
		var nextPic = window.currentPic + 1;
		var nextClass = class_stub + nextPic;
		document.getElementById(id_target).className = nextClass; 
		window.currentPic++;
	}
	else{
		var nextPic = 1;
		var nextClass = class_stub + nextPic;
		document.getElementById(id_target).className = nextClass; 
		window.currentPic=1;
	}
};

sw = function(){ 
	setInterval("advance()", time_interval);
};