//http://www.dlr.de/daily-life/slideshow-js-tutorial.html

var DHTML = (document.getElementById || document.all || document.layers);
if ( !DHTML ) alert('Your browser is not capable of displaying DHTML');
function getObj(name) {
	if (document.getElementById) {
		this.style = document.getElementById(name).style;
	} else
	if (document.all) {
		this.style = document.all[name].style; 
		} else
		if (document.layers) {
		this.style = document.layers[name];
		}
	}
		
		function visib(objName, flag) {
		x = new getObj(objName);
		x.style.visibility = (flag) ? 'visible' : 'hidden';}
		
		var curImg = 0; // index of the array entry
		var lastImg = 0;
		function changeSlide ( change ) {
			if (!DHTML) return;
			curImg += change;
			if ( curImg < 0 ) curImg = slides.length-1;
			else
			if ( curImg >= slides.length ) curImg = 0;
			visib(slides[lastImg], false);
			visib(slides[curImg], true);
			lastImg = curImg;
			}
			
			slides = new Array('slide0','slide1','slide2','slide3','slide4','slide5','slide6','slide7','slide8','slide9','slide10','slide11','slide12','slide13','slide14','slide15','slide15','slide16','slide17','slide18','slide19','slide20','slide21','slide22','slide23','slide24','slide25','slide26','slide27','slide28','slide29','slide30','slide31','slide32','slide33','slide34','slide35','slide36','slide37','slide38','slide39','slide40','slide41','slide42','slide43','slide44','slide45','slide46');