function setCookie(name,value,expiredays)
	{
		var cookieDate = new Date()
		cookieDate.setTime(cookieDate.getTime() + expiredays * 24 * 60 * 60 * 1000)
		document.cookie = name + "=" + value + ";expires="+ cookieDate.toGMTString() 
	}
	
	function getCookie(name)
	{
		var cookieData = new String(document.cookie)
		var cookieHeader = name + "="
		var cookieStart = cookieData.indexOf(cookieHeader) + cookieHeader.length
		var cookieEnd = cookieData.indexOf(";", cookieStart)
		if(cookieEnd == -1){
			cookieEnd = cookieData.length
		}
		if(cookieData.indexOf(cookieHeader) != -1){
			return cookieData.substring(cookieStart, cookieEnd)
		}
		else {
			return null 
		}
	}
	
	function spustreklamu(blok, pole){
	    var reklama = document.getElementById(blok);
		var kolac = getCookie(blok);
		var pocet = pole.length;
		
		if(kolac == null || kolac >= pocet-1){
			setCookie(blok, 0 ,"1");
			reklama.innerHTML = pole[0];
		}
        else {
            var poradi = parseInt(kolac) + 1;
            setCookie(blok, poradi, "1");
			reklama.innerHTML = pole[poradi];
		}
	}