源码：
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<script>
var perCount = parseInt(prompt("请输入班级人数："));
var perScores = [];
for (var i = 0; i < perCount; i++) {
//成绩存入数组
perScores[perScores.length] = parseInt(prompt("请输入第" + (i + 1) + "个学生的成绩："));
}
var sum = 0;
var max = perScores[0];
var min = perScores[0];
for (i = 0; i < perCount; i++) {
//总成绩
sum += perScores[i];
//最高分
if (max < perScores[i]) {
max = perScores[i];
}
//最低分
if (min > perScores[i]) {
min = perScores[i];
}
}
console.log(perScores);
console.log("总成绩：" + sum);
console.log("平均成绩：" + sum / perCount);
console.log("最高分：" + max);
console.log("最低分：" + min);
</script>
</body>
</html>