一个使用数组和循环的简单的主谋游戏

Question

这是我为一个班级做的一个项目。我还是一个初学者，所以这个主题只应该涵盖到字符串、循环和数组。如果你对游戏不熟悉的话，进阶版就是这个。然而，我的任务是一个更简单的版本。以下是这个版本的规则。

程序开始时要求第一个玩家，即代码制造者，输入一个用于游戏的模式。图案长4个字母，每个字母代表一种颜色（R为红色，G为绿色）。
为了简化游戏，只有两种颜色可以使用，红色和绿色。因此，例如，用户可以输入RRGR来表示Red Red Green Red，或者他们可以输入GGGG来表示Green Green Green Green。为简化起见，您可以假设模式将仅由R和/或G组成，代码生成器将不会输入不正确的字符或符号。但是，您必须检查代码生成器输入的是4个字符（它是4个字符长，而不是5个字符长，也不是3个字符长）。如果他们没有，您需要提示直到他们做到。代码生成器可以输入大小写字母，您应该能够处理它。

Code maker, please enter a pattern of 4 colors (the possible colors are R=red and G=green):

GGGR

What is the maximum number of guesses allowed for this game?

4

Okay, now it's the code breaker's turn. You have 4 chances to guess the pattern. Enter a guess:

RRRR

The code maker sets out 1 black pegs and 0 white pegs. 

Enter a guess:

GGRG

The code maker sets out 2 black pegs and 2 white pegs

Enter a guess:

GGGR

You got the pattern! The code breaker wins!

这是我正在关注的代码（计算黑色引脚）。到目前为止，我的问题是，我无法使插针与每一个数组内容相匹配。基本上，它总是导致4个引脚，即使有的时候它应该是3个引脚或2个。如果需要，整个未完成的代码在此部分下面。

String pattern = keys.nextLine().toUpperCase(); // this is used to enter the original pattern
String attempt = keys.nextLine().toUpperCase(); // this is to enter an attempt

String pattern_array [] = new String [5];
String attempt_array [] = new String [5];

int i;          
int black_pegs = 0;
for (i=0; i<pattern.length(); i++) {
    pattern_array[i] = pattern.substring(i,(i+1)); 
}
for ( i=0; i<attempt.length();i++) {
    attempt_array[i] = attempt.substring(i,i+1);
}
for (int x=0; x<4; x++) {
    if (pattern_array[i]==attempt_array[i]) {
        black_pegs++;
    }
}

这是我的代码，我已经到目前为止（请随意看一看，并指出其他事情，如果你愿意）

import java.util.Scanner;
public class CopyOfAssignment5 {
    public static void main(String[] args) {
        Scanner keys = new Scanner(System.in);
        System.out.println("Codemaker, please enter a pattern of 4 colors (the possible colors are R=red and G=green");
        String pattern = keys.nextLine().toUpperCase();
        System.out.println("What is the maximum number of guesses for this game?");
        int number_of_guesses = keys.nextInt();
        int turns = number_of_guesses + 1;
        System.out.println();
        System.out.println();
        System.out.println();
        System.out.println();
        System.out.println("Okay, now its the codebreaker's turn. You have " + number_of_guesses
                + " chances to guess the pattern");
        System.out.println("Enter a Guess:");

        int white_pegs = 0, black_pegs = 0;
        String pattern_array[] = new String[5];
        String attempt_array[] = new String[5];
        String attempt = null;

        while (turns > 0) { // while turns are not zero
            attempt = keys.nextLine().toUpperCase(); // then keep displaying the scanner input for an attempt.
            turns--;
        }
        if (attempt.equals(pattern)) { // if you get the correct patter, then you win. Loops stops.
            System.out.println("You got the pattern! The codebreaker wins!");
        }
        if (turns == 0 && !(attempt.equals(pattern))) {
            System.out
                    .println("The codemaker sets out " + black_pegs + " black pegs and " + white_pegs + " white pegs.");
            System.out.println("Sorry, that was your last chance. You lost.");
        } else if (turns < turns) {
            System.out
                    .println("The codemaker sets out " + black_pegs + " black pegs and " + white_pegs + " white pegs.");
            System.out.println("Enter a Guess:");
        }

        int i;
        for (i = 0; i < pattern.length(); i++) {
            pattern_array[i] = pattern.substring(i, (i + 1));
        }
        for (i = 0; i < attempt.length(); i++) {
            attempt_array[i] = attempt.substring(i, i + 1);
        }
        for (int x = 0; x < 4; x++) {
            if (pattern_array[i] == attempt_array[i]) {
                black_pegs++;
            }
        }
    }
}

Answer 1

下面是我的实现。我不会解释代码，因为你已经接受了一个答案。也许你还是想比较一下你的代码和我的。也许其他人会在这个问题上找到答案，并从下面的代码中得到一些好处。

public class MstrMind {
    private static final char  BLACK = 'B';
    private static final char  WHITE = 'W';
    private static final int  CODE_LENGTH = 4;

    private static String getCode(Scanner stdin) {
        System.out.println("Code maker, please enter a pattern of " + CODE_LENGTH + " colors (the possible colors are R=red and G=green):");
        String code = stdin.nextLine();
        while (!isCodeValid(code)) {
            System.out.println("Entered code does not contain " + CODE_LENGTH + " colors.");
            System.out.println("Code maker, please enter a pattern of " + CODE_LENGTH + " colors (the possible colors are R=red and G=green):");
            code = stdin.nextLine();
        }
        return code.toUpperCase();
    }

    private static int getGuesses(Scanner stdin) {
        System.out.print("What is the maximum number of guesses allowed for this game? ");
        int guesses = stdin.nextInt();
        stdin.nextLine();
        return guesses;
    }

    private static boolean guess(Scanner stdin, String code) {
        System.out.print("Enter a guess: ");
        String guess = stdin.nextLine();
        char[] flags = new char[CODE_LENGTH];
        int blackCount = 0;
        int whiteCount = 0;
        for (int i = 0; i < CODE_LENGTH; i++) {
            if (guess.charAt(i) == code.charAt(i)) {
                flags[i] = BLACK;
                blackCount++;
            }
            else {
                for (int j = 0; j < CODE_LENGTH; j++) {
                    if (guess.charAt(j) == code.charAt(i)  &&  flags[j] == 0  &&  i != j) {
                        flags[j] = WHITE;
                        whiteCount++;
                    }
                }
            }
        }
        boolean guessed = blackCount == CODE_LENGTH;
        if (!guessed) {
            System.out.printf("The code maker sets out %d black pegs and %d white pegs.%n",
                              blackCount,
                              whiteCount);
        }
        else {
            System.out.println("You got the pattern! The code breaker wins!");
        }
        return guessed;
    }

    private static boolean isCodeValid(String code) {
        return code != null && code.length() == CODE_LENGTH;
    }

    private static void playGame(Scanner stdin, String code, int guesses) {
        int guess = guesses;
        boolean guessed = false;
        while (guess > 0  &&  !guessed) {
            guessed = guess(stdin, code);
            guess--;
        }
        if (!guessed) {
            System.out.println("Code breaker failed to break the code. Code maker wins.");
        }
    }

    public static void main(String[] args) {
        Scanner stdin = new Scanner(System.in);
        String code = getCode(stdin);
        int guesses = getGuesses(stdin);
        System.out.printf("Okay, now it's the code breaker's turn. You have %d chances to guess " +
                                                                                  "the pattern.%n",
                          guesses);
        playGame(stdin, code, guesses);
    }
}