function setCookie(name, value, expires, path, domain, secure)
{
	var newCookie = name+"="+escape(value)+
	((expires) 	? ";expires="	+ expires.toGMTString() :"") +
	((path) 	? ";path=" 		+ path					:"") +
	((domain)	? ";domain="	+ domain				:"") +
	((secure)	? ";secure"								:"");
	document.cookie=newCookie;
}

function getCookie(name)
{
	var prefix = name+"=";
	var start  = document.cookie.indexOf(prefix);
	if (-1==start)
		return null;
	var end = document.cookie.indexOf(";", start+prefix.length);
	if (-1==end)
		end = document.cookie.length;
	var value = document.cookie.substring(start+prefix.length, end);
	return unescape(value);
}

// числа от 0 до count с увеличением на 1 с каждым разом
function seq_number(count) 
{
	var cName = "bann_offset";
	var pos   = getCookie(cName);
	
	if (!pos)
		pos = -1 + Math.round(Math.random() * count);
	
	pos ++;
	
	if (pos >= count)
		pos = 0;

	setCookie(cName, pos);
	return pos;
}