2

我已经搜索过，根本找不到我的问题的答案。我必须创建一个乐透类型模拟，6 个号码 + 奖金号码，没有重复。我已经设法让它工作了，但是在 6 个数字数组中，位置 [1] 处的数字一直显示为 0。我确定这是一个简单的问题，但我对此很陌生，所以任何帮助都将被感激地接受.下面的代码，我敢肯定它到处都是......

import java.util.Arrays;

public class Lotto {

    public static void main(String[] args) {

        int[] Lotto=new int[6];
        final int MIN = 1;
        final int MAX = 45;

        for (int i = 0; i< Lotto.length; ++i)
        {

            Lotto [0] =MIN+ (int)(Math.random()*((MAX -MIN)+1));

            while (Lotto[1] == Lotto[0])
            {
                Lotto[1] =MIN+ (int)(Math.random()*((MAX -MIN)+1));
            }

            while ((Lotto[2] == Lotto[0]) || (Lotto[2] == Lotto[1]) )
            {
                Lotto[2] = MIN+ (int)(Math.random()*((MAX -MIN)+1));

            while ((Lotto[3] == Lotto[0]) || (Lotto[3] == Lotto[1]) || (Lotto[3] == Lotto[2]) )
            {
                Lotto[3] = MIN+ (int)(Math.random()*((MAX -MIN)+1));
            }

            while  ((Lotto[4] == Lotto[0]) || (Lotto[4] == Lotto[1]) || (Lotto[4] == Lotto[2]) ||   (Lotto[4] == Lotto[3]) )                        

            {
                Lotto[4] = MIN+ (int)(Math.random()*((MAX -MIN)+1));



                while  ((Lotto[5] == Lotto[0]) || (Lotto[5] == Lotto[1]) || (Lotto[5] == Lotto[2]) ||   (Lotto[5] == Lotto[3])||    (Lotto[5] == Lotto[4])) 

                {
                    Lotto[5] = MIN+ (int)(Math.random()*((MAX -MIN)+1));
                }


                int[] BonusNumber=new int[1];
                for (int j = 0; j< BonusNumber.length; ++j)
                {

                    BonusNumber [j] =1+ (int)(Math.random()*((45 -1)+1));
                }

                System.out.println("Winner  "  + Arrays.toString(Lotto));
                System.out.println("Bonus Number" +Arrays.toString(BonusNumber));   
            {


    }
            }
            }
        }
    }
}
4

5 回答 5

5

改变这个循环：

while (Lotto[1] == Lotto[0])
{
    Lotto[1] = random(MIN, MAX);
}

进入：

do {
    Lotto[1] = random(MIN, MAX);
} while (Lotto[1] == Lotto[0]);

以及相应的其余代码。你看到问题出在哪里了吗？

但是在你开始重写你相当复杂和不可维护的代码之前，检查一下这个实现，它更容易理解并且......正确：

final int MIN = 1;
final int MAX = 45;

final List<Integer> allPossible = new ArrayList<Integer>(MAX - MIN + 1);
for (int i = MIN; i <= MAX; ++i) {
    allPossible.add(i);
}
Collections.shuffle(allPossible);
final List<Integer> lotto = allPossible.subList(0, 6);
int bonusNumber = allPossible.get(6);

System.out.println("Winner  "     + lotto);
System.out.println("Bonus Number" + bonusNumber);

Collections.shuffle()在这里至关重要。

于 2013-01-08T20:31:16.387 回答
3

我认为你的代码很混乱，你可以通过使用一些 API 实用程序来避免这么多条件，例如Collections.shuffle()在这个例子中：

public static void main(String[] args) 
{
    Integer[] numbers = new Integer[45];

    // Populating numbers.
    for (int i = 0; i < 45; i++)
        numbers[i] = i + 1;

    // Shuffling them to make them in random order.
    List<Integer> list = Arrays.asList(numbers);
    Collections.shuffle(list);

    // Print any 6 of them. I chose first 6 ones for simplicity.
    for (int i = 0; i < 6; i++)
        System.out.print(list.get(i) + " ");
}

样本输出：

15 11 31 2 5 38
于 2013-01-08T20:35:34.320 回答
2

您可以使用HashSet既不保持顺序也不保持重复的 a 。

您还可以在java.util.Random每次需要新的随机数时创建该类的新实例，因为这会更改种子并为您的应用程序提供更多随机性，从而消除每次包含 0 的位置 1。

new java.util.Random().nextInt(int max)

于 2013-01-08T20:28:02.347 回答
1

如果您想使用 int[] 而不是内置类，您可以这样做

int[] ints = new int[45];
for (int i = 0; i < ints.length; i++) ints[i] = i + 1;
Random rand = new Random();
for (int i = 0; i < 6; i++) {
    int swap = rand.nextInt(ints.length - i) + i;
    int tmp = ints[i];
    ints[i] = ints[swap];
    ints[swap] = tmp;
}
int[] drawn = Arrays.copyOf(ints, 6);
System.out.println(Arrays.toString(drawn));

印刷

[19, 22, 24, 6, 34, 23]
于 2013-01-08T20:49:46.527 回答
0

我想我正在学习与您相同的 Java 入门课程（因为该程序看起来非常熟悉）所以我将尝试将其保留为基本内容；但是，我确实从您的程序中复制了所有原始代码，所以您基本上完成了所有工作，我只是稍微清理了一下。

这是完整的程序（随机化一组数字（检查重复），允许用户选择一组或随机化自己的一组（也检查重复），对两组进行排序和比较，通知用户他们是否中奖，要求再次播放：

import java.util.*;
    public class Lotto
    {
    public static void main(String[] args)
    {        
        Scanner keyboard = new Scanner(System.in);
        Random rand = new Random();
        boolean checkPlay = false, readInput = false;
        final int MAX = 45;

        while (readInput != true)
        {
            System.out.print("Would you like to buy a lotto ticket? [y/n] ");
            String stBuyTicket = keyboard.nextLine().trim().toLowerCase();

            if (stBuyTicket.isEmpty())
            {
                System.out.println("Invalid Input.");
            }
            else if (stBuyTicket.charAt(0) == 'y' || stBuyTicket.charAt(0) == 'n')
            {
                if (stBuyTicket.charAt(0) == 'y')
                {
                    checkPlay = true;
                }
                else
                {
                    checkPlay = false;                    
                }
                readInput = true;
            }
            else
            {
                System.out.println("Invalid Input.");
            }
        }        
        while (checkPlay == true)
        { 
            int[] lotto = new int[6];
            int lottoLength = lotto.length;
            int[] userLotto = new int[6];
            int userLottoLength = userLotto.length;
            for (int i = 0; i < lottoLength; i++)
            {
                boolean checkLotto = false;
                while (checkLotto != true)
                {  
                    int numCheck = (rand.nextInt(MAX) + 1);
                    boolean confirmSame = false;
                    for (int j = 0; j <= i; j++)
                    {
                        if (numCheck == lotto[j])
                        {
                            confirmSame = true;
                        }
                    }
                    if (confirmSame != true)
                    {
                        lotto[i] = numCheck;
                        checkLotto = true;                                               
                    }
                }
            }            
            readInput = false;
            while (readInput != true)
            {
                System.out.println("Would you like choose your own numbers or just randomize them?");
                System.out.print("Choose your own numbers? [y/n] ");            
                String stBuyTicket = keyboard.nextLine().trim().toLowerCase();
                if (stBuyTicket.isEmpty())
                {
                    System.out.println("Invalid Input.");
                }
                else if (stBuyTicket.charAt(0) == 'y' || stBuyTicket.charAt(0) == 'n')
                {
                    if (stBuyTicket.charAt(0) == 'y')
                    {
                        for (int i = 0; i < userLottoLength; i++)
                        {
                            boolean checkUserLotto = false;
                            while (checkUserLotto != true)
                            {
                                System.out.print("Which number would you like to choose for number " + (i + 1) + ": ");
                                String numUserInput = keyboard.nextLine().trim();

                                int numUserInputLength = numUserInput.length();
                                boolean checkInput = true;
                                if (numUserInputLength > 2 || numUserInputLength < 1)
                                {
                                    System.out.println("Invalid Input. Try again.");
                                    checkInput = false;
                                }
                                else
                                {
                                    for (int j = 0; j < numUserInputLength; j++)
                                    {
                                        if (Character.isDigit(numUserInput.charAt(j)) != true)
                                        {
                                            System.out.println("Invalid Input. Try again.");
                                            checkInput = false;
                                        }
                                    }
                                }
                                if (checkInput == true)
                                {
                                    int userInput = Integer.parseInt(numUserInput);
                                    if (userInput > MAX || userInput < 1)
                                    {
                                        System.out.println("Invalid Input. Try again.");
                                    }
                                    else
                                    {
                                        boolean confirmSame = false;
                                        for (int j = 0; j <= i; j++)
                                        {
                                            if (userInput == userLotto[j])
                                            {
                                                System.out.println("You've already choosen this number. Choose again.");
                                                confirmSame = true;
                                            }
                                        }
                                        if (confirmSame != true)
                                        {
                                            userLotto[i] = userInput;
                                            checkUserLotto = true;
                                        }
                                    }
                                }
                            }
                        }
                    }
                    else
                    {
                        for (int i = 0; i < userLottoLength; i++)
                        {                            
                            boolean checkLotto = false;
                            while (checkLotto != true)
                            {  
                                int numCheck = (rand.nextInt(MAX) + 1);
                                boolean confirmSame = false;                                
                                for (int j = 0; j <= i; j++)
                                {
                                    if (numCheck == userLotto[j])
                                    {
                                        confirmSame = true;
                                    }
                                }
                                if (confirmSame != true)
                                {
                                    userLotto[i] = numCheck;
                                    checkLotto = true;                                               
                                }
                            }
                        } 
                    }
                    readInput = true;
                    System.out.print("Your lotto numbers are: " + userLotto[0]);
                    for (int i = 1; i < userLottoLength; i++)
                    {
                        System.out.print(", " + userLotto[i]);
                    }
                    System.out.print("!");
                    System.out.println();

                    System.out.print("And the winning lotto numbers are: " + lotto[0]);
                    for (int i = 1; i < lottoLength; i++)
                    {
                        System.out.print(", " + lotto[i]);
                    }
                    System.out.print("!");
                    System.out.println();

                    Arrays.sort(lotto);
                    Arrays.sort(userLotto);

                    if (Arrays.equals(userLotto, lotto) == true)
                    {
                        System.out.println("Your lotto numbers match the winning lotto numbers! \nYou win!");
                    }
                    else
                    {
                        System.out.println("Your lotto numbers do not match the winning lotto numbers. \nYou lose.");
                    }
                }
                else
                {
                    System.out.println("Invalid Input.");
                }
            }
            readInput = false;
            while (readInput != true)
            {
                System.out.print("Would you like to buy another lotto ticket? [y/n] ");
                String stBuyTicket = keyboard.nextLine().trim().toLowerCase();

                if (stBuyTicket.isEmpty())
                {
                    System.out.println("Invalid Input.");
                }
                else if (stBuyTicket.charAt(0) == 'y' || stBuyTicket.charAt(0) == 'n')
                {
                    if (stBuyTicket.charAt(0) == 'y')
                    {
                        checkPlay = true;
                    }
                    else
                    {
                        checkPlay = false;
                    }
                    readInput = true;
                }
                else
                {
                    System.out.println("Invalid Input.");
                }
            }
        }
        System.out.println("That's a good decision. Save your money");
        System.exit(0);
    }
}

以下是随机化乐透集而不重复的部分：

for (int i = 0; i < lottoLength; i++) {
                boolean checkLotto = false;
                while (checkLotto != true) {  
                    int numCheck = (rand.nextInt(MAX) + 1);
                    boolean confirmSame = false;
                    for (int j = 0; j <= i; j++) {
                        if (numCheck == lotto[j]) {
                            confirmSame = true;
                        }
                    }
                    if (confirmSame != true) {
                        lotto[i] = numCheck;
                        checkLotto = true;                                               
                    }
                }
            }

它生成一个数字，int numCheck = (rand.nextInt(MAX) + 1)并根据迄今为止输入的每个乐透号码检查该号码：

for (int j = 0; j <= i; j++) {
    if (numCheck == lotto[j]) {
        confirmSame = true;
    }
}

如果numCheck不等于任何输入的数字，则numCheck写入当前数组点。

于 2013-02-14T18:00:19.577 回答