function delCookie() {
  var name = 'cname';
  var exp = new Date();
  exp.setTime(exp.getTime() - 1); // This cookie is history
  var cval = GetCookie(name);
  if (cval != null)
     document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}


function GetCookie(name) {
   var arg = name + "=";
   var alen = arg.length;
   var clen = document.cookie.length;
   var i = 0;
   while (i < clen) {
      var j = i + alen;
      if (document.cookie.substring(i, j) == arg)
         return getCookieVal(j);
      i = document.cookie.indexOf(" ", i) + 1;
      if (i == 0) 
         break;
   }
   return null;
}

function getCookieVal(offset) {
   var endstr = document.cookie.indexOf(";", offset);
   if (endstr == -1) endstr = document.cookie.length;
   return unescape(document.cookie.substring(offset, endstr));
}

function SetCookieForNHours(name, value, hours, path, domain, secure) {
   var today = new Date();
   var expires = new Date(today.getTime() + hours*60*60*1000);
   document.cookie = name + "=" + escape(value) +
       "; expires=" + expires.toGMTString() +
       ((path) ? "; path=" + path : "") +
       ((domain) ? "; domain=" + domain : "") +
       ((secure) ? "; secure" : "");
}

function memoryTab(cookie_val) {
   if (cookie_val == 'office') {
      SetCookieForNHours('office', 1, 24*30, '/');
   } else {
      SetCookieForNHours('office', 0, 24*30, '/');
   }
}