我应该如何修复我的 Monty Python 游戏（C#），将奖品隐藏在随机门后面，并使显示的门是随机的，但不是奖品门？

Question

我试图为我的期末项目创建一个基本的 Monty Python 游戏。我不知道如何将奖品放入随机门或打开随机门。我搜索了其他资源，但找不到任何信息来帮助我完成这项任务。谢谢你。

这是我尝试运行的代码，但出现了越界异常：

using System;
class Guess
{
    static void Main (string[] args)
    {
        Dictionary<int, string> Door = new Dictionary<int, string>();
        Door.Add(1, "Nothing");
        Door.Add(2, "Car");
        Door.Add(3, "Nothing");
        Random rng = new Random();
        int x = rng.Next(0, Door.Count);
        int doors = Door.Keys.ElementAt(x);
        string prize = Door.Values.ElementAt(x);
        int n = Door.Count;
        int PrizeDoor = Convert.ToInt32(new Random());
        Console.WriteLine("Which door do you want to select?");
        int SelectedDoor = Convert.ToInt32(Console.ReadLine());
        int RevealedDoor = Convert.ToInt32(new Random());
        Console.WriteLine("Do you want to change your selection?");
        string selection = Console.ReadLine();

        if (selection == "Yes")
        {
            // ask user which new door to choose
            Console.WriteLine("Which door would you like to choose now?");
            int NewSelectedDoor = Convert.ToInt32(Console.ReadLine());
            if (NewSelectedDoor == SelectedDoor)
            {
                Console.WriteLine("You cannot select the same door twice. Please try again.");
            }
            else if (NewSelectedDoor == PrizeDoor)
            {
                Console.WriteLine("Congratulations! You won the game!");
                return;
            }
            else
            {
                Console.WriteLine("Sorry, you lost the game!");
                return;
            }
        }
        else
        {
            // stay with same door and reveal what's in the door
            if (SelectedDoor == PrizeDoor)
            {
                Console.WriteLine("Congratulations! You won the game!");
                return;
            }
            else
            {
                Console.WriteLine("Sorry, you lost the game!");
                return;
            }
        }

    }
}

有什么建议吗？谢谢你。

Answer 1

我在您的代码中看到的第一个问题，这导致它抛出异常并且无法在all：

工作

Convert.ToInt32(new Random());

new Random()

创建一个类型为

Random

的新对象。这是一个随机数生成器类，它不能转换为整数。

回答你的第一个问题，如何将奖品隐藏在随机门后面？

不要像这里那样手动在 1 和 3 处添加“Nothing”，并在 2 处添加“Car”：

Door.Add(1, "Nothing");
Door.Add(2, "Car");
Door.Add(3, "Nothing");

您需要使用随机数生成器（您使用

Random rng = new Random();

创建的）来随机生成奖品将位于哪扇门后面。假设您使用三扇门，这是典型的“蒙蒂霍尔问题”门数，这就是我要做的。这可能不是最有效的方法，但我正在努力将其保持在初学者水平。

// instantiate your doors dictionary
// and random number generator
Dictionary<int, string> doors = new Dictionary<int, string>();
Random rng = new Random();

int totalNumberOfDoors = 3;

// use your random number generator to generate a number
// between 1 (inclusive) and 4 (exclusive)
// whatever number it generates, that's what door the prize is behind
int prizeBehindDoor = rng.Next(1, totalNumberOfDoors + 1);

// fill your doors dictionary now
// I'm using a plain for loop b/c it's a basic concept
// it starts at 1 because your doors are numbered "1", "2", "3" and not "0", "1", and "2"
for (int i = 1; i <= totalNumberOfDoors; i++)
{
    // if `i` is the door the prize is behind, add "Car"
    if (i == prizeBehindDoor)
    {
        doors.Add(i, "Car");
    }
    // otherwise, add "Nothing"
    else
    {
        doors.Add(i, "Nothing");
    }
}

现在你的门字典在随机位置有“汽车”，在另外两个位置有“无”。

回答你的第二个问题，如何才能让显示的门是随机的，而不是奖品门？

我假设您尚未使用 LINQ，因此我将为您提供一个不使用 LINQ 的解决方案。再说一遍，有更干净、更优化的方法可以做到这一点，但我会让你自己解决这部分问题。我的回答更多的是从概念上为您指出正确的方向。

// the prize could be behind any of the 3 doors,
// so you can't JUST randomly generate a number between 1 and 3 again
// because it might pick the one with the prize

// so let's assign the door numbers that AREN'T the prize to a list
List<int> nonPrizeDoors = new List<int>();

// loop thru the keys of your doors dictionary, and only add items that are not the prize
// the "keys" of the dictionary are your door numbers (1, 2, and 3)
// there's definitely other ways of doing this
foreach (int key in doors.Keys)
{
    // only add this key to "nonPrizeDoors" if it's NOT the prize
    if (key != prizeBehindDoor)
    {
        nonPrizeDoors.Add(key);
    }
}
// now your "nonPrizeDoors" list contains all the door numbers that are not prize doors

// now you want to use your random number generator to randomly pick one of those
// you're picking an array/list INDEX here
// so you want to generate a number between 0 (inclusive) and the number of items in the list (exclusive)
int randomIndex = rng.Next(0, nonPrizeDoors.Count);

// remember that was just the INDEX,
// saying which of the (two) items in the Keys list you're going to choose
// now you want to get the randomly-chosen Key (door number)
int chosenDoorNumber = nonPrizeDoors[randomIndex];

// now you can get that item from the doors dictionary, and do whatever you need with it
string chosenDoor = doors[chosenDoorNumber];    // will be "Nothing"

此时，您可以使用

chosenDoorNumber

和

chosenDoor

做任何您需要的事情。显示给用户等