var which=1

function slideshow(){
	for(var i=0;i < arr.length; i++){
		document.getElementById("cont" + (i+1)).style.display='none'
	}
	document.getElementById("cont" + which).style.display=''
	if(which < arr.length){
		which+=1
	}else{
		which=1
	}
	setTimeout("slideshow()",2500)
}

function alphaslideshow(){
	for(var i=0;i < arr.length; i++){
		document.getElementById("cont" + (i+1)).style.display='none'
	}
	document.getElementById("cont" + which).style.display=''
	if(which < arr.length){
		which+=1
	}else{
		which=1
	}
	setTimeout("slideshow()",4000)
}