Java 创建循环是一个随机值，每次循环重新启动时都会更改

我正在做一个抛硬币模拟器，但我有一个随机值的问题。我需要创建一个随机值，每次while循环再次启动时都会更改

    System.out.println("How many times do I flip the coin?");
    int repetition;
    int heads = 0;
    int tails = 0;
        Scanner amount_of_times = new Scanner(System.in);
    repetition = amount_of_times.nextInt();
    double luck = (Math.random());
    do {
        if (luck > 0.5)
            heads++ ;
        else
            tails++ ;
        repetition --;
    } while (repetition > 0);
    System.out.println("The amount of heads was " + heads + ", meanwhile the amount of tails was " + tails + ".");
        amount_of_times.close();
    }
}

---

在循环之前，

luck

只分配一次值。如果希望它在每次迭代中获得不同的值，则应将赋值移动到循环内的：

do {
    double luck = Math.random(); // Here!
    if (luck > 0.5)
        heads++ ;
    else
        tails++ ;
    repetition --;
} while (repetition > 0);

Move

double luck=（Math.random（））在循环中请参见：。