let score = prompt("请输入成绩:");//输入成绩
let a = parseInt(score / 10);//将字符串转换为数字
switch (a) {
case 6:
console.log(`成绩为${score},成绩等级为D`);
break;
case 7:
console.log(`成绩为${score},成绩等级为C`);
break;
case 8:
console.log(`成绩为${score},成绩等级为B`);
break;
case 9:
console.log(`成绩为${score},成绩等级为A`);
break;
default:
console.log(`成绩为${score},成绩等级为E`);
break;
}