Question

我是Java的新手，并试图通过做一些我在网上找到的练习来学习。如果这太天真，请原谅我。

这个练习是关于用以下规则编写掷骰子游戏的程序：

在掷骰子游戏中，传球线下注如下：两个六面骰子冷轧;掷骰子的第一骰子被称为“滚出来”。 7或11的自动输出会自动获胜，并且会出现2,3或12的输出自动输了。如果在出来的卷筒上滚动4,5,6,8,9或10，那么这个数字成为“重点”。玩家继续掷骰子直到7点或者点卷起。如果该点首先滚动，则玩家赢得下注。如果首先滚动7，然后球员输了。使用这些规则编写一个模拟掷骰子游戏的程序，无需人工输入。该计划不应该要求下注，而应该计算是否球员会赢或输。该程序应该模拟滚动两个骰子和计算总和。添加循环以使程序播放10,000个游戏。加计算玩家获胜次数的次数，以及玩家获胜的次数球员输了。在10,000场比赛结束时，计算获胜的概率 [即Wins /（胜利+损失）]并输出该值。从长远来看，谁是赢得大多数比赛，你还是房子？

这是我写的代码：

// GAME OF CRAPS
public static void main (String[] args)
{
  int dice1 = 0;
  int dice2 = 0;
  int scorenew = 0;
  int point = 0;
  int wins = 0;
  int loss = 0;

  for (int i = 0; i < 10000; i++)
  {
    System.out.println ("roll the dices");
    int score = roll (dice1, dice2);
    System.out.println ("\n score " + score);

    if (score == 11 || score == 7)
    {
      System.out.println ("\n Score = " + score);
      System.out.println ("you win");
      wins = wins + 1;
    }
    if (score == 2 || score == 3 || score == 12)
    {
      System.out.println ("\n Score = " + score);
      System.out.println ("you lose");
      loss = loss + 1;
    }
    else if (score == 4 || score == 5 || score == 6 || score == 8 || score == 9 || score == 10)
    {
      point = point + score;
      System.out.println ("\n Point = " + point);

      do
      {
        scorenew = roll (dice1, dice2);
        System.out.println ("\n Score new = " + scorenew);
        if (scorenew == point)
        {
          System.out.println ("\n you win");
          wins = wins + 1;
          point = 0;
          break;
        }
        if (scorenew == 7)
        {
          System.out.println ("\n you lose");
          point = 0;
          loss = loss + 1;
          break;
        }
      } while (scorenew != point || scorenew != 7);

    }
  }

  System.out.println ("\n number of wins = " + wins
    + " and number of loss = " + loss +
    " and the probability for winning a game = " + (double) wins / (wins + loss));
}

public static int roll (int d1, int d2)
{
  Random randomGenerator = new Random ();
  int dice1 = randomGenerator.nextInt (6) + 1;
  int dice2 = randomGenerator.nextInt (6) + 1;

  System.out.println ("\n dice1 = " + dice1 + " dice2 = " + dice2);

  int score = dice1 + dice2;
  return score;
}

每次我运行代码时，do-while条件首先被执行，所以请任何人帮我弄清楚我哪里出错了？

Answer 1

do {
} while(scorenew!=point || scorenew != 7);

这个条件总是为真，所以你有一个无限循环。另外，为什么要将d1和d2传递到roll()函数中？它们完全未使用且不需要。

Answer 2

同时正在做你应该期望的事情。首先执行主体然后评估条件以查看它是否应该再次运行。你实际上并不需要做什么，但是你想要运行，直到其中一个条件让你摆脱了while循环。

else {
  point = score;
  System.out.println ("\n Point = " + point);

  while (true) {
    scorenew = roll (dice1, dice2);
    System.out.println ("\n Score new = " + scorenew);
    if (scorenew == point) {
      System.out.println ("\n you win");
      wins = wins + 1;
      break;
    }
    if (scorenew == 7) {
      System.out.println ("\n you lose");
      loss = loss + 1;
      break;
    }
  }
}

喜欢@Lee Daniel Crocker说你不需要将dice1和dice2传递给roll功能。

public static int roll() {
  Random randomGenerator = new Random();
  int dice1 = randomGenerator.nextInt(6) + 1;
  int dice2 = randomGenerator.nextInt(6) + 1;
  System.out.println("\n dice1 = " + dice1 + " dice2 = " + dice2);
  return dice1 + dice2;
}

另一个可能有用的方法是不在方法顶部声明所有变量。你不需要重新分数或者指出第三个条件之外的东西，事实上你不需要重新分数，因为你有点：

public static void main(String[] args) throws java.lang.Exception {
  int wins = 0;
  int loss = 0;

  for (int i = 0; i < 10000; i++) {
    System.out.println("roll the dices");
    int score = roll();
    System.out.println("\n score " + score);

    if (score == 7 || score == 11) {
      System.out.println("\n Score = " + score);
      System.out.println("you win");
      wins = wins + 1;
    } else if (score == 2 || score == 3 || score == 12) {
      System.out.println("\n Score = " + score);
      System.out.println("you lose");
      loss = loss + 1;
    } else {
      int point = score;
      System.out.println("\n Point = " + point);
      while (true) {
        score = roll();
        System.out.println("\n Score new = " + score);
        if (score == point) {
          System.out.println("\n you win");
          wins = wins + 1;
          break;
        }
        if (score == 7) {
          System.out.println("\n you lose");
          loss = loss + 1;
          break;
        }
      }
    }
  }

  System.out.println("\n number of wins = " + wins
      + " and number of loss = " + loss +
      " and the probability for winning a game = " + (double) wins / (wins + loss));
}

public static int roll() {
  ...
}

JAVA中骰子的模拟游戏

2 个答案: