java - 循环和/或 if else 双返回

Question

我正在尝试编写一个程序来玩骰子游戏，用户下注高低或七。到目前为止，我已经成功地掷骰子并添加了正确的部分，但我的投注功能进展不顺利。这是我到目前为止所拥有的:

import java.util.Random;
import java.util.Scanner;

public class Project07
{
  public static void main(String[] args)
  {
    Scanner keyboard = new Scanner(System.in);
    Random r = new Random();
    int money = 100;
    int newtotal = 100;
    System.out.println("You have " + money + " dollars");
    while (money > 0)
    {
      System.out.println("Enter an amount to be or 0 to quit");
      int bet = keyboard.nextInt();
      if (bet == 0)
      {
        System.out.println("You end with " + money + " dollars");
        System.exit(0);
      }

      System.out.println("Bet 1 for high, 2 for low, or 3 for 7's");
      int choose = keyboard.nextInt();
      int diceb = r.nextInt(7 - 1) + 1;
      int dicea = r.nextInt(7 - 1) + 1;
      int dicetotal = dicea + diceb;
      System.out.println(dicetotal);
      System.out.println("You bet $" + bet);
      if ((choose == 1) && (dicetotal > 7))
      {
        newtotal = newtotal + bet;
        System.out.println("You win $" + bet);
        System.out.print("You have " + newtotal + " dollars left");
      }
      else if ((choose == 1) && (dicetotal <= 7))
      {
        newtotal = newtotal - bet;
        System.out.println("You have " + newtotal + "dollars left");
      }
      else if ((choose == 2) && (dicetotal < 7))
      {
        newtotal = newtotal + bet;
        System.out.println("You have " + newtotal + "dollars left");
      }
      else if ((choose == 2) && (dicetotal >= 7))
      {
        newtotal = newtotal - bet;
        System.out.println("You have " + newtotal + "dollars left");
      }
      else if ((choose == 3) && (dicetotal == 7))
      {
        newtotal = newtotal + bet;
        System.out.println("You have " + newtotal + "dollars left");
      }
      else if ((choose == 3) && (dicetotal != 7))
        ;
      {
        newtotal = newtotal - bet;
        System.out.println("You have " + newtotal + "dollars left");
      }
    }
  }
}

我得到的输出应该是这样的:你有 100 美元输入金额或 0 退出20投注 1 表示高，投注 2 表示低，或投注 3 表示 7111您下注 20 美元您赢得 20 美元您还剩 120 美元输入金额或 0 退出0你最终得到 120 美元

然而，它似乎激活了 if else block 的获胜和失败部分，并给我这个:你有 100 美元输入金额或 0 退出20投注 1 表示高，投注 2 表示低，或投注 3 表示 7111您下注 20 美元您赢得 20 美元您还剩 120 美元 您还剩 100 美元输入金额或 0 退出0你最终得到 100 美元

不太确定我的问题出在哪里，也许我需要专门为它的下注功能编写一个新方法？任何帮助将不胜感激。

Answer 1

格式正确(两种主要样式之一):

public static void main(String[] args) {
    Scanner keyboard = new Scanner(System.in);
    Random r = new Random();
    int money = 100;
    int newtotal = 100;
    System.out.println("You have " + money + " dollars");
    while (money > 0) {
        System.out.println("Enter an amount to be or 0 to quit");
        int bet = keyboard.nextInt();
        if (bet == 0) {
            System.out.println("You end with " + money +" dollars");
            System.exit(0);
        }
        System.out.println("Bet 1 for high, 2 for low, or 3 for 7's");
        int choose = keyboard.nextInt();
        int diceb = r.nextInt(7 - 1) + 1;
        int dicea = r.nextInt(7 - 1) + 1;
        int dicetotal = dicea + diceb;
        System.out.println(dicetotal);
        System.out.println("You bet $" + bet);
        if ((choose == 1) && (dicetotal >7)) {
            newtotal= newtotal + bet; 
            System.out.println("You win $" + bet); 
            System.out.print("You have " + newtotal +" dollars left");
        }
        else if ((choose == 1) && (dicetotal <= 7)) { 
            newtotal = newtotal - bet; 
            System.out.println("You have " + newtotal + "dollars left"); 
        }
        else if ((choose == 2) && (dicetotal < 7)) {
            newtotal = newtotal + bet; 
            System.out.println("You have " + newtotal  + "dollars left");
        }
        else if ((choose == 2) && (dicetotal >= 7)) {
            newtotal = newtotal - bet; 
            System.out.println("You have " + newtotal  + "dollars left");
        }
        else if ((choose == 3) && (dicetotal == 7)) {
            newtotal = newtotal + bet; 
            System.out.println("You have " + newtotal + "dollars left");
        }
        else if ((choose == 3) && (dicetotal != 7)); { <<== Wayward semicolon!!
            newtotal = newtotal - bet; 
            System.out.println("You have " + newtotal  + "dollars left");
        }
    }
}

任性的分号是显而易见的，因为除了行尾之外，你永远不会在任何地方放置分号。浏览代码并查看 if 条件很容易 - 您不必将它们从困惑中挖掘出来。从缩进可以明显看出 while 结束的位置。

(另一种主要样式是将 { 字符放在自己的行上:

        ...
        }
        else if ((choose == 1) && (dicetotal <= 7))
        { 
            newtotal = newtotal - bet; 
            System.out.println("You have " + newtotal + "dollars left"); 
        }
        else if ((choose == 2) && (dicetotal < 7))
        {
            newtotal = newtotal + bet; 
            System.out.println("You have " + newtotal  + "dollars left");
        }
        ...

我不太喜欢这种风格，因为它过多地分散了文本(并且在尝试阅读和理解大型程序时屏幕空间很有值(value))，而且因为任性的 ; 情况下，; 不合适的情况并不那么明显。)

(还有一种样式将结束 } 与以下 else 放在同一行:

        ...
        } else if ((choose == 1) && (dicetotal <= 7)) { 
            newtotal = newtotal - bet; 
            System.out.println("You have " + newtotal + "dollars left"); 
        } else if ((choose == 2) && (dicetotal < 7)) {
        ...

这更紧凑，但在我看来太紧凑了，并且开始变得困惑。另外，它使得不可能在 else 之前放置注释行。但其他人有不同的偏好。主要选择一种风格并坚持下去，并在团队中尝试同意一个共同的方案(不要对此感到压抑)。