<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<script type="text/javascript">
var biangliang = prompt("请输入班级的总人数");
var num = 0;
var fang = true;
for (let index = 1; index <=biangliang; index++) {
var a = prompt("请输入第"+index+"个学员的成绩:");
if (a>=80) {
num++;
}else if(a<0){
fang = false;
break;
}
}
if (fang) {document.write("80分以上的学员个数是"+num+"<br/>");
}else{
document.write("学员的成绩有误，请重新输入"+"<br/>");
}
</script>
</body>
</html>
