骰子加倍 Java 练习 - 逻辑错误

Question

我是一名初学者，通过在线资源自学 Java。我遇到过这个练习。

编写一个程序，通过从 1-6 中选择一个随机数，然后从 1-6 中选择第二个随机数来模拟掷骰子。将两个值相加，并显示总数。修改你的骰子游戏，让它一直滚动，直到它们得到双倍（两个骰子上的数字相同）。

到目前为止我有这个代码：

public class DiceGame {
public static void main(String[] args) {

    System.out.println("ROLL THE DICE!\n");

    int firstRoll = 1 + (int) (Math.random() * 6);

    int secondRoll = 1 + (int) (Math.random() * 6);

    while (firstRoll != secondRoll) {
        System.out.println("Roll #1: " + firstRoll);
        System.out.println("Roll #2: " + secondRoll);
        int total = firstRoll + secondRoll;
        System.out.println("The total is " + total);
    }
    System.out.println("You rolled doubles!");
    System.out.println("Roll #1: " + firstRoll);
    System.out.println("Roll #2: " + secondRoll);
    int total = firstRoll + secondRoll;
    System.out.println("The total is " + total);
}
}

问题是，当我运行此代码时，如果两个滚动不同，程序将永远运行，输出相同的第一个和第二个滚动值和总数...我确定我有一个逻辑错误while 循环。请帮忙。

这是我的输出示例：

Roll #1: 2
Roll #2: 3
The total is 5

Roll #1: 2
Roll #2: 3
The total is 5

Roll #1: 2
Roll #2: 3
The total is 5

Roll #1: 2
Roll #2: 3
The total is 5

Roll #1: 2
Roll #2: 3
The total is 5

Roll #1: 2
Roll #2: 3
The total is 5

Roll #1: 2
Roll #2: 3
The total is 5

Roll #1: 2
Roll #2: 3
The total is 5

Roll #1: 2
Roll #2: 3
The total is 5

（while 条件不断返回 false 并打印相同的值）

以下是所需输出的示例：

Roll #1: 3
Roll #2: 5
The total is 8

Roll #1: 6
Roll #2: 1
The total is 7

Roll #1: 2
Roll #2: 5
The total is 7

Roll #1: 1
Roll #2: 1
The total is 2

（程序应该在滚动双打时结束）

Answer 1

如果它们的值不同，您必须再次掷骰子。

在这种情况下使用do-while 很好。

int firstRoll, secondRoll;
do {
    firstRoll = 1 + (int) (Math.random() * 6);
    secondRoll = 1 + (int) (Math.random() * 6);
    System.out.println("Roll #1: " + firstRoll);
    System.out.println("Roll #2: " + secondRoll);
    int total = firstRoll + secondRoll;
    System.out.println("The total is " + total);
} while (firstRoll != secondRoll);

Answer 2

您需要在每次迭代中再次滚动：

while (firstRoll != secondRoll) {
    System.out.println("Roll #1: " + firstRoll);
    System.out.println("Roll #2: " + secondRoll);
    int total = firstRoll + secondRoll;
    System.out.println("The total is " + total);
    firstRoll = 1 + (int) (Math.random() * 6);
    secondRoll = 1 + (int) (Math.random() * 6);
}

Answer 3

编写一个方法public int roll()，并在其中放置计算1-6之间随机数的逻辑。您只是输出 firstRoll 和 secondRoll 的结果，而不是在方法中再次计算它。

例子：

    public class Dice() {
        public int roll() {
         return 1 + (int) (Math.random() * 6);
        }
    }

并使用它：

Dice d1 = new Dice();
Dice d2 = new Dice();

int d1Result = d1.roll();
int d1Result = d2.roll();

while (d1Result != d2Result) {
d1Result = d1.roll();
d2Result = d2.roll();

System.out.println("Result d1: " + d1Result);
System.out.println("Result d2: " + d2Result);
 // Rest of logic ... 

}