static void Main(string[] args)
{
var chatRoom = new ChatRoom();
var user1 = new CommonUser("小明");
var user2 = new GoldenUser("小豪");
var user3 = new Administrator("小蛤");
chatRoom.register(user1);
chatRoom.register(user2);
chatRoom.register(user3);
user1.send("Hello,world");
user2.send("买辆兰博基尼怎么样");
user3.send("开门，快递");
Console.ReadKey();
}
