27-if双分支语句-闰年判断案例.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // let user = prompt("请输入用户名")
        // let passwd = prompt("请输入密码")
        // if (user === "zhangsan" && passwd === "123456") {
        //     alert("欢迎登录")
        // } else {
        //     alert("账户名或密码错误")
        // }

        let year = +prompt("请输入年份")
        if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) {
            alert(year+"是闰年")
        } else {
            alert(year + "不是闰年")
        }
    </script>
</body>
</html>