制作一个随机询问用户5个问题而不重复问题的程序[重复]

Posted 2023-03-30

【中文标题】制作一个随机询问用户5个问题而不重复问题的程序[重复]

【英文标题】：Making a program that ask the user 5 questions in random without duplicate the questions [duplicate]

【发布时间】：2013-01-29 17:12:41

【问题描述】：

可能重复：Randomize a List<T> in C#

我想制作一个程序，随机问用户 5 个问题而不重复问题，如果问题是正确的，如果错误则继续下一个问题，直到他给出正确的答案，这就是我的代码已经写了，但是还是有一些问题，比如有重复，当用户输入错误的答案时，它只会停止一次，然后程序就关闭了！ 现在如何防止重复相同的问题，如果他输入错误的值不要继续下一个问题或程序关闭？

static void Main()

    next:
    Random question = new Random();
    int x = question.Next(5);
    string[] array = new string[5];
    array[0] = "-What is the capital of France";
    array[1] = "-What is the capital of Spain";
    array[2] = "-What is the captial of Russia";
    array[3] = "-What is the capital of Ukraine";
    array[4] = "-What is the capital of Egypt";

    Console.WriteLine(array[x]);

    string[] answer = new string[5];
    answer[0] = "Paris";
    answer[1] = "Madrid";
    answer[2] = "Moscow";
    answer[3] = "Kiev";
    answer[4] = "Cairo";

    string a = Console.ReadLine();

    if (a == answer[x])
    
        Console.WriteLine("It's True \n*Next Question is:");
        goto next;
    
    else
        Console.WriteLine("It's False \n*Please Try Again.");

    Console.ReadLine();

【问题讨论】：

请提出具体问题（如有必要，请提出多个问题），而不是“这不起作用，请修复”类型之一。也请删除此goto。

天啊，请不要使用 GOTO。 That's the Devil himself

@ken2k .. 我已经更新了这个问题并这样做了！ :)

@HighCore .. 我可以用什么代替？！

@user2022523 Flow Control

【参考方案1】：

您可以使用 LINQ 随机排列所问问题的索引

Random random = new Random();
var indexes = Enumerable.Range(0,array.Length).OrderBy(i => random.Next());

foreach(var index in indexes)

    Console.WriteLine(array[index]);
    do 
            
        string a = Console.ReadLine();

        if (a == answer[index])                 
          Console.WriteLine("It's True\n");
          break;
        

        Console.WriteLine("It's False \n*Please Try Again.");
    
    while(true);

解释：

Enumerable.Range(0,array.Length) 将返回从零开始的整数值范围：0, 1, 2, 3, 4。接下来，这些数字将按随机数排序（即随机排列）。它可能导致这些数字的任何组合，例如3, 0, 1, 4, 2.

---

顺便说一句，最好采用 OOP 方式并将相关数据（问题文本和答案）和逻辑（定义答案是否正确）放在一个地方：

public class Question

    public string Text  get; set; 
    public string Answer  get; set; 

    public bool IsCorrect(string answer)
    
        return String.Compare(answer, Answer, true) == 0;
    

有了这个问题类，你的所有代码都将更具可读性：

var questions = new List<Question>()

    new Question  Text = "What is the capital of France?", Answer = "Paris" ,
    new Question  Text = "What is the capital of Spain?", Answer = "Madrid" ,
    new Question  Text = "What is the capital of Russia?", Answer = "Moscow" ,
    new Question  Text = "What is the capital of Ukraine?", Answer = "Kiev" ,
    new Question  Text = "What is the capital of Egypt?", Answer = "Cairo" 
;

Random random = new Random();

// randomizing is very simple in this case
foreach (var question in questions.OrderBy(q => random.Next()))

    Console.WriteLine(question.Text);

    do
    
        var answer = Console.ReadLine();
        if (question.IsCorrect(answer))
        
            Console.WriteLine("It's True");
            break;
        

        Console.WriteLine("It's False. Please try again.");
    
    while (true);

下一步是实现Survey 类，它将进行提问、阅读答案和显示摘要。

【讨论】：

还有更多efficient algorithm 可以随机播放列表。但是，此解决方案可以快速实施。

在这种情况下，绝对不是。我也很想知道你为什么被否决。

@lazyberezovsky - 哈哈！我完全同意你的看法！而且，不客气。

@lazyberezovsky .. 谢谢！老兄，它太有用了，而且很有效:) 太棒了

@lazyberezovsky .. 我当然会，但我不能在“7 小时”之前这样做，所以我一定会 :)

【参考方案2】：

除非绝对必要，否则不要使用 goto。

public class Program

    private static List<KeyValuePair<string, string>> questions = new List<KeyValuePair<string, string>>
    
        new KeyValuePair<string,string>("-What is the capital of France", "Paris"),
        new KeyValuePair<string,string>("-What is the capital of Spain", "Madrid"),
        new KeyValuePair<string,string>("-What is the captial of Russia", "Moscow"),
        new KeyValuePair<string,string>("-What is the capital of Ukraine", "Kiev"),
        new KeyValuePair<string,string>("-What is the capital of Egypt", "Cairo"),
    ;

    static void Main()
    
        var questions = ShuffleQuestions();

        foreach(var question in questions)
        
            bool done = false;
            while(!done)
            
                Console.WriteLine(question.Key);
                string a = Console.ReadLine();

                if (a == question.Value)
                
                    Console.WriteLine("It's True \n*Next Question is:");
                    done = true;
                
                else
                    Console.WriteLine("It's False \n*Please Try Again.");
            
        

        Console.ReadLine();
    

    private IEnumerable<KeyValuePair<string, string>> ShuffleQuestions()
    
        var list = questions;
        var random = new Random();  
        int items = list.Count;  
        while (items > 1)   
            items--;  
            int nextItem = random.Next(items + 1);  
            var value = list[nextItem];  
            list[nextItem] = list[items];  
            list[items] = value;  
        

        return list;
    

【参考方案3】：

您可以创建一个无序的整数数组，代表提出问题的顺序：

// Create question order
var order = Enumerable.Range(0, array.Length).ToArray();
for (int i = order.Length - 1; i > 1; --i)

    var randomIndex = rnd.Next(i);
    var temp = order[randomIndex];
    order[randomIndex] = order[i];
    order[i] = temp;


// Ask the questions in shuffled order
foreach(int questionIndex in order)

    Console.Write(array[questionIndex]);
    bool answeredCorrectly = Console.ReadLine() == answer[questionIndex];