Question

我刚刚开始学习Java，所以我可能甚至走不上正确的路线，但我的作业要求我创建21游戏。游戏的工作方式是玩家和计算机轮流输入1 ，2或3。输入数字达到或超过21的玩家将输。我似乎遇到的麻烦是，当输入最后一个数字时，我似乎无法让程序退出循环，它会显示玩家每次输赢（输赢）。

我尝试在do-while循环后使用另一个if语句来显示“ You Win！”。或“您迷路了”。但是，我无法弄清楚应该在if语句中使用哪些参数来确定谁赢了。我还尝试将游戏设置为将玩家设置为偶数，将计算机设置为奇数，但我无法将数字添加到正在运行的总数中以结束循环。

  int numLoops = 0;
  int firstCheck;
  int points;
  Scanner input = new Scanner(System.in);

  do
  {
     System.out.print("\nEnter a 1, 2, or 3 >> ");
     points = input.nextInt();

     int random = (int )(Math.random() *  3 + 1);
     numLoops = points + numLoops + random;

     if(numLoops < 21)
     {
        System.out.println("The computer entered a " + random);         
        System.out.println("The new total is " + numLoops);
     }
     else
     {
        //This is what always prints.
        System.out.println("You lost! The computer is the victor.");
     }
  }while(numLoops < 21);
  //this is what I am having most of my trouble with.
  System.out.println("You Win!");

我希望循环将在总数达到21之后关闭，并输出一条语句，该语句根据获胜者而有所不同。但是，程序总是输出玩家输了。

Answer 1

如果进行了一些更改以简化操作。看看源代码，它应该有充分的文档记录，并能最好地说明事情。

/*
 * Which players turn is it?
 * (true for human player, false for computer)
 */ 
boolean isHumanPlayersTurn = true;
int totalPoints = 0;

Scanner input = new Scanner(System.in);

// the game ending condition
while (totalPoints < 21) {

    // take an action, depending on the players turn
    if (isHumanPlayersTurn) {
        System.out.print("\nEnter a 1, 2, or 3 >> ");
        totalPoints += input.nextInt();
    } else {
        int random = (int) (Math.random() * 3 + 1);
        System.out.println("The computer takes " + random);
        totalPoints += random;
    }

    System.out.println("Total amount is " + totalPoints);

    /*
     * Important part: After each players move, change the players turn, but do NOT
     * do this if the game already ended, since then the other player would have won.
     */
    if (totalPoints < 21) {
        isHumanPlayersTurn = !isHumanPlayersTurn;
    }
}

// now, the player to move is the one who loses
if (isHumanPlayersTurn) {
    System.out.println("You lost! The computer is the victor.");
} else {
    System.out.println("You Win!");
}

Answer 2

在用户输入数字之后，您应立即检查是否达到21（并在该点输出总和）。如果未击中21，则计算机应该进行猜测，然后再次检查以查看是否击中21。因此，您将拥有两个if语句（每次猜测后一个；用户/计算机）。在用户猜测之后的else块中，计算机将猜测。您的if语句将检查> = 21，表示适当时对用户或计算机造成了损失。您无需在循环外声明胜利者，因为可以在循环内完成...

例如：

    int total = 0;
    do
    {
        System.out.print("\nEnter a 1, 2, or 3 >> ");
        points = input.nextInt();
        total = total + points;
        System.out.println("The new total is " + total);

        if (total >=21)
        {
            System.out.println("You lost! The computer is the victor.");
        }
        else
        {
            int random = (int )(Math.random() *  3 + 1);
            total = total + random;
            System.out.println("The computer entered a " + random);         
            System.out.println("The new total is " + total);

            if(total >= 21)
            {
                System.out.println("You Win!");
            }
        }
    }while(total < 21);

如何使用if语句了解播放器或计算机是否获胜？

2 个答案: