有没有大神可以解析一下这串代码..
<!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 nowday=new Date();
var weekday=["星期一","星期二","星期三","星期四","星期五","星期六","星期天"];
document.write(
nowday.getFullYear()+"年"+
nowday.getMonth()+"月"+
nowday.getDate()+"日"+
weekday[nowday.getDay()]+"</br>"
);
var sorceStr = "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 sourceArr = sorceStr.split(";");
var score = new Array();
var sum = 0;
for (var i = 0; i < sourceArr.length; i ++) {
sum += parseInt(sourceArr[i].substr(sourceArr[i].indexOf(";")+1));
//document.write("<br>" + sum);//test
}
document.write("--班级总分为:" + sum);
document.write(",班级平均分为(保留整数):" + Math.round(sum/sourceArr.length))
//从数组中将成绩撮出来，然后求和取整，并输出。
</script>
</head>
<body>
</body>
</html>
sum += parseInt(sourceArr[i].substr(sourceArr[i].indexOf(";")+1));
