求大佬看一下错误
<!DOCTYPE HTML>
<html >
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>系好安全带,准备启航</title>
<script type="text/javascript">
var mydate=new Date();
var weekday=["星期日","星期一","星期二","星期三","星期四","星期五","星期六"];
var scoreStr = "小明:87;小花:81;小红:97;小天:76;小张:74;小小:94;小西:90;小伍:76;小迪:64;小曼:76";
var abc=scoreStr.split(";");
var sum=0;
for(var i=0;i<abc.length-1;i++){
sum+=parseInt(abc[i].substr(cell[i].indexOf(":")+1));
}
document.write(mydate.getFullYear()+"年"+mydate.getMonth()+1+"月"+mydate.getDate()+"日"+" "+weekday[mydate.getDay()]+"--"+"班级总分为："+sum);
</script>
</head>
<body>
</body>
</html>
这两处的有问题