function setCookie(c_name,value,expiredays)
{
	var exdate=new Date()
	exdate.setDate(exdate.getDate()+expiredays)
	document.cookie=c_name+ "=" +escape(value)+
	((expiredays==null) ? "" : ";expires="+exdate.toGMTString())
}

function getCookie(c_name)
{	
	if (document.cookie.length>0)
	{
		c_start=document.cookie.indexOf(c_name + "=")
		if (c_start!=-1)
		{ 
			c_start=c_start + c_name.length+1 
			c_end=document.cookie.indexOf(";",c_start)
			if (c_end==-1) c_end=document.cookie.length
			return unescape(document.cookie.substring(c_start,c_end))
		} 
	}
	return ""
}

function changeImages(c_name,path1,path2,path3)
{
	if(getCookie(c_name))
	{
		var a  = getCookie(c_name);

		if(a == 1)
		{
			document.getElementById("HeaderImage").src=path1;
			setCookie(c_name,'2',1);
		}
			
		if(a == 2)
		{
			document.getElementById("HeaderImage").src=path2;
			setCookie(c_name,'3',1);
		}
			
		if(a == 3)
		{
			document.getElementById("HeaderImage").src=path3;
			setCookie(c_name,'1',1);
		}
	}
	else
	{
		setCookie(c_name,'1',1);
			document.getElementById("HeaderImage").src=path3;
	}
}