حل تمرین از طریق دستورات شرطی if :

var adminPassword = 'TheMaster';
var result = prompt('Who\\'s there?', 'example: Hossein');
if(result === "Admin") {
    var password = prompt('Password?');
    if (password === adminPassword){
        alert('welcome!');
    } else if (password == null) {
        alert('canceled.');
    } else {
        alert('Wrong passwrod ...!');
    }   
} else if (result == null) {
    alert('canceled.');
} else {
    alert('i don\\'t know you ...!');
}

حل تمرین از طریق ternary :

var userName = prompt('Who\\'s there?', 'example: Hossein');
userName == 'Admin' 
    ? 
    adminPassword = prompt('Password?') 
    : 
        userName == null 
        ? 
            alert('canceled') 
            : 
            alert('idon\\'t know you');
adminPassword == 'TheMaster' 
    ? 
    alert('welcom') 
    : 
        adminPassword == null 
        ? 
        alert('canceled')
        :
        alert('Wrong Password');

حل تمرین از طریق Switch :

var userName = prompt('Who\\'s there?', 'example: Hossein');
switch (userName) {
    case 'Admin':
        adminPassword = prompt('Password');
        switch (adminPassword){
            case 'TheMaster':
                alert('welcom');
                break;
            case null:
                alert('canceled');
                break;
            default:
                alert('Wrong Password');
                break;
        }
        break;
    case null:
        alert('canceled');
        break;
    default:
        alert('i don\\'t know you')
        break;
}