奶牛和公牛隊代碼--Japan

Question

我是一名CS學生，剛剛開始，我被困在奶牛和公牛隊的比賽中。它編譯並運行，但是某種地方存在某種錯誤，我沒有看到導致牛和公牛的錯誤數量（預期與我的輸出樣本）。

母牛和公牛的解釋：公牛 - 正確的位數。母牛 - 如果它們處於正確位置，那麼它們的位數就是正確的。

public class CowsAndBulls{ 

    //Constants 
    public final static int NUM_DIGITS = 4; 
    public final static int MAX_VALUE = 9876; 
    public final static int MIN_VALUE = 1234; 
    public final static int MAX_GUESSES = 10; 
    // 


    // instances 
    private NumberPicker randomNumber; 
    private int answer; 
    private int guessesCopy; 
    private int bullStored; 
    private int cowStored; 
    // 

    public CowsAndBulls(int seed){ 
     randomNumber = new NumberPicker(seed, MIN_VALUE, MAX_VALUE); 
     answer = randomNumber.nextInt(); 
     guessesCopy = MAX_GUESSES; 
     } 

    //////////////////////////////////////////////////////// 
    //Stuff between the comments is from a previous question that needs to be used in CowsAndBulls (not in a package) - I know it works as it's supposed to. 
    public static int[] toArray(int number){ 

     String numString = Integer.toString(number); 
     int[] someArray = new int[numString.length()]; 

     for (int i = 0; i < numString.length(); i++){ 
       char c = numString.charAt(i); 

       int cVal = Character.getNumericValue(c); 

       someArray[i] = cVal; 
       } 
     return someArray; 
       } 

    public static int countMatches(int a, int b){ //Bulls 

     String stringA = Integer.toString(a); 
     int lengthAB = stringA.length(); 
     int count = 0; 

     int[] arrayOutA = toArray(a); 
     int[] arrayOutB = toArray(b); 

     for (int i = 0; i < lengthAB; i++){ 
       if (arrayOutA[i] == arrayOutB[i]) 
        count += 1;  
          }     
     return count; 
     } 


    public static int countIntersect(int numA, int numB){ //Cows 
     String stringA = Integer.toString(numA); 
     int lengthAB = stringA.length(); 
     int count = 0; 

     int[] arrayOutA = toArray(numA); 
     int[] arrayOutB = toArray(numB); 

     for (int i = 0; i < lengthAB; i++){ 

       for (int j = 0; j < lengthAB; j++){ 

        if (arrayOutA[i] == arrayOutB[j]){ 
          count += 1; 
          } 
          } 

        } 
        return count; 
        } 
    //////////////////////////////////////////////////////////////////       






    public int guessesRemaining(){ 
     return guessesCopy; 
     } 



    public Result guess(int guessNumber){ 

     int bulls = countMatches(answer, guessNumber); 
     bullStored = bulls; 
     int cows = countIntersect(answer, guessNumber); 
     cowStored = cows; 

     guessesCopy--; 
     return (new Result(cows, bulls)); 
     } 

    public int giveUp(){ 
     return (answer); 
     } 

    public boolean gameOver(){ 
     if (guessesCopy == 0 || bullStored == 4) 
       return true; 
     else 
       return false;     
     } 

下面是我們應該使用並不能編輯它的任何方式所提供的課程：NumberPicker，遊戲，和結果。 NumberPicker：

import java.util.ArrayList; 
    import java.util.Collections; 
    import java.util.List; 
    import java.util.Random; 
    /** 
    * Given a number range, a NumberPicker returns the numbers in the range in a random order 
    */ 
    public class NumberPicker { 

      private List<Integer> numbers; 

    /** 
     * Create a NumberPicker that uses the given seed value for randomisation and that 
     * returns the numbers in the range min to max (inclusive) in a random order. 
     */
     public NumberPicker(final int seed, final int min, final int max) { 
      numbers = new ArrayList<Integer>(); 
      final Random random = new Random(seed); 
      for(int i = min; i<max+1; i++) { 
      numbers.add(i); 
       } 
      Collections.shuffle(numbers, random); 
      } 

     /** 
     * Determine whether the NumberPicker contains any more numbers.. 
     */ 
     public boolean hasNext() { return !numbers.isEmpty(); } 

     /** 
     * Return a randomly selected number from the range. 
     */ 
     public int nextInt() { return numbers.remove(0); } 

    } 

遊戲類：

   import java.util.Scanner; 

      public class Game { 

      private Game() {} 

      public static void main(String[] inputs) { 
     Scanner input = new Scanner(System.in); 
     System.out.println("Your challenge is to guess a secret " + CowsAndBulls.NUM_DIGITS + " digit number."); 

     System.out.println("Enter randomisation seed value:"); 
     CowsAndBulls cowsAndBulls = new CowsAndBulls(input.nextInt()); 

     System.out.println("Make a guess:"); 
     Result answer = cowsAndBulls.guess(input.nextInt()); 

     while(!answer.isCorrect()&&cowsAndBulls.guessesRemaining()>0) { 

      System.out.println("Sorry that's incorrect."); 
      System.out.println("You have "+answer+"."); 

      System.out.printf("You have %d guesses remaining\n", cowsAndBulls.guessesRemaining()); 
      System.out.println("Make a guess:"); 
      answer = cowsAndBulls.guess(input.nextInt()); 
      } 
     if (answer.isCorrect()) { 
      System.out.println("Correct !"); 
      } 
     else { 
      System.out.println("Sorry, you lose."); 
      } 
      } 
     } 

最後，結果等級：

  /** 
      * A Result object records the outcome of a guess in the Cows and Bulls guessing game. 
      * 
      * 
      */ 
     public class Result { 

      private int cows; 
      private int bulls; 

     public Result(int cows, int bulls) { 
      assert(cows+bulls<=4); 
      this.cows=cows; 
      this.bulls=bulls; 
      } 

     public int cows() { return cows; } 
     public int bulls() { return bulls; } 

     public boolean isCorrect() { return bulls==4; } 

     public boolean equals(Object o) { 
      if (!(o instanceof Result)) { 
       return false; 
       } 
      else { 
       Result other = (Result)o; 
       return this.cows()==other.cows()&&this.bulls()==other.bulls(); 
      } 
     } 

     public String toString() { 
      String result = this.cows()+(this.cows()!=1 ? " cows" : " cow"); 
      result = result+" and "+this.bulls()+(this.bulls()!=1 ? " bulls" : " bull"); 
      return result; 
      } 

    } 

這是所有的代碼。重申：除了CowsAndBulls之外，我不能更改任何類，我必須使用Game，Result和NumberPicker。下面是預期產出與什麼我的計劃是生產...

 Trial 1: Output not correct 

     The expected output was: 
     10 
     false 
     8913 
     true 

     Your program produced: 
     10 
     false 
     7407 
     false 

     Input supplied to your program: 
     construct 3 
     guessesRemaining() 
     gameOver() 
     giveUp() 
     gameOver() 
     Q 

     ------------------------------------- 
     Trial 2: Output not correct 

     The expected output was: 
     10 
     0 cows and 0 bulls 
     9 
     1 cow and 0 bulls 
     8 
     2 cows and 0 bulls 
     7 
     3 cows and 0 bulls 
     6 
     4 cows and 0 bulls 
     5 

     Your program produced: 
     10 
     1 cow and 0 bulls 
     9 
     0 cows and 0 bulls 
     8 
     1 cow and 0 bulls 
     7 
     2 cows and 0 bulls 
     6 
     2 cows and 0 bulls 
     5 

     Input supplied to your program: 
     construct 4 
     guessesRemaining() 
     guess() 2358 
     guessesRemaining() 
     guess() 1235 
     guessesRemaining() 
     guess() 1735 
     guessesRemaining() 
     guess() 1749 
     guessesRemaining() 
     guess() 1746 
     guessesRemaining() 
     Q 
     ---------------------------------------------- 
     Trial 3: Output not correct 

     The expected output was: 
     10 
     0 cows and 0 bulls 
     9 
     0 cows and 1 bull 
     8 
     0 cows and 2 bulls 
     7 
     0 cows and 3 bulls 
     6 
     0 cows and 4 bulls 
     5 
     true 

     Your program produced: 
     10 
     1 cow and 0 bulls 
     9 
     1 cow and 0 bulls 
     8 
     1 cow and 0 bulls 
     7 
     1 cow and 0 bulls 
     6 
     1 cow and 0 bulls 
     5 
     false 

     Input supplied to your program: 
     construct 8 
     guessesRemaining() 
     guess() 2358 
     guessesRemaining() 
     guess() 2758 
     guessesRemaining() 
     guess() 2748 
     guessesRemaining() 
     guess() 6748 
     guessesRemaining() 
     guess() 6741 
     guessesRemaining() 
     gameOver() 
     Q 

這可能只是愚蠢的事情是我沒有看到，但任何幫助是極大的讚賞。我是S.E（和Java）的新手，所以我的代碼的格式可能很奇怪 - 如果是這樣，我會編輯它。謝謝 ：）。

Answer 1

The expected output was: 
    10 
    false 
    8913 
    true 

    Your program produced: 
    10 
    false 
    7407 
    false 

    Input supplied to your program: 
    construct 3 
    guessesRemaining() 
    gameOver() 
    giveUp() 
    gameOver() 
    Q 

據我可以告訴它告訴你，它從giveUp（）期望的數字是不正確的。這表明你的程序以某種方式產生不同的數字（7404 vs 8913）。 這可能是由於您的MIN_VALUE和/或MAX_VALUE？

public static int countIntersect(int numA, int numB) { //Cows 
    String stringA = Integer.toString(numA); 
    int lengthAB = stringA.length(); 
    int count = 0; 

    int[] arrayOutA = toArray(numA); 
    int[] arrayOutB = toArray(numB); 

    for (int i = 0; i < lengthAB; i++) { 

     for (int j = 0; j < lengthAB; j++) { 

      if (arrayOutA[i] == arrayOutB[j]) { 
       count += 1; 
      } 
     } 

    } 
    return count; 
} 

我不認爲這是你想要的。例如countIntersect（1111,1111）會返回16，我預計這是4或0？

至於你的編碼這裏是一些小的反饋：

在功能giveUp你不需要的（和）在return語句。

// Original 
public int giveUp() { 
    return (answer); 
} 

// Suggested 
public int giveUp() { 
    return answer; 
} 

在您的guess函數中，您不需要先將其保存在本地int中。還有（和）再次。

// Original 
public Result guess(int guessNumber) { 

    int bulls = countMatches(answer, guessNumber); 
    bullStored = bulls; 
    int cows = countIntersect(answer, guessNumber); 
    cowStored = cows; 

    guessesCopy--; 
    return (new Result(cows, bulls)); 
} 

// Suggested 
public Result guess(int guessNumber) { 
    bullStored = countMatches(answer, guessNumber); 
    cowStored = countIntersect(answer, guessNumber); 
    guessesCopy--; 
    return new Result(cowStored, bullStored); 
} 

在您的方法countIntersect中，沒有真正的理由使用特殊的int []數組。字符數組也可以做得很好。 另外，lengthAB可以被2個數組之一的.length屬性替換。

// Original 
public static int countIntersect(int numA, int numB) { //Cows 
    String stringA = Integer.toString(numA); 
    int lengthAB = stringA.length(); 
    int count = 0; 

    int[] arrayOutA = toArray(numA); 
    int[] arrayOutB = toArray(numB); 

    for (int i = 0; i < lengthAB; i++) { 
     for (int j = 0; j < lengthAB; j++) { 
      if (arrayOutA[i] == arrayOutB[j]) { 
       count += 1; 
      } 
     } 
    } 
    return count; 
} 

// Suggested 
public static int countIntersect(int numA, int numB) { //Cows 
    int count = 0; 

    char[] arrayA = Integer.toString(numA).toCharArray(); 
    char[] arrayB = Integer.toString(numB).toCharArray(); 

    for (int i = 0; i < arrayA.length; i++) { 
     for (int j = i; j < arrayB.length; j++) { 
      if (arrayA[i] == arrayB[j]) { 
       if(i != j) { 
        count++; 
       } 
       break; 
      } 
     } 
    } 
    return count; 
} 

與countMatches相同。

// Original 
public static int countMatches(int a, int b){ //Bulls 

    String stringA = Integer.toString(a); 
    int lengthAB = stringA.length(); 
    int count = 0; 

    int[] arrayOutA = toArray(a); 
    int[] arrayOutB = toArray(b); 

    for (int i = 0; i < lengthAB; i++){ 
     if (arrayOutA[i] == arrayOutB[i]) 
      count += 1; 
    } 
    return count; 
} 

// Suggested 
public static int countMatches(int a, int b) { //Bulls 
    int count = 0; 

    char[] arrayA = Integer.toString(a).toCharArray(); 
    char[] arrayB = Integer.toString(b).toCharArray(); 

    for (int i = 0; i < Math.min(arrayA.length,arrayB.length); i++) { 
     if (arrayA[i] == arrayB[i]) 
      count += 1; 
    } 
    return count; 
} 

最後你的gameOver可以寫得更簡單。

//Original 
public boolean gameOver() { 
    if (guessesCopy == 0 || bullStored == 4) 
     return true; 
    else 
     return false; 
} 

// Suggested 
public boolean gameOver() { 
    return guessesCopy == 0 || bullStored == 4; 
}