Question

我有一个程序，旨在模拟一些概率问题（如果你感兴趣，可以改变monty hall问题）。

在经过足够的迭代之后，代码预计会产生50％，但在java中它总是达到60％（即使在1000000次迭代之后），而在C＃中它出现在预期的50％是否有一些不同我不知道的事情java的随机可能吗？

以下是代码：

import java.util.Random;

public class main {


    public static void main(String args[]) {
        Random random = new Random();

        int gamesPlayed = 0;
        int gamesWon = 0;

        for (long i = 0; i < 1000l; i++) {

            int originalPick = random.nextInt(3);
            switch (originalPick) {
            case (0): {
                // Prize is behind door 1 (0)
                // switching will always be available and will always loose
                gamesPlayed++;
            }
            case (1):
            case (2): {
                int hostPick = random.nextInt(2);
                if (hostPick == 0) {
                    // the host picked the prize and the game is not played
                } else {
                    // The host picked the goat we switch and we win
                    gamesWon++;
                    gamesPlayed++;
                }
            }
            }
        }

        System.out.print("you win "+ ((double)gamesWon / (double)gamesPlayed )* 100d+"% of games");//, gamesWon / gamesPlayed);
    }

}

Answer 1

至少，您忘记使用case语句结束每个break块。

所以对此：

switch (x)
{
case 0:
    // Code here will execute for x==0 only

case 1:
    // Code here will execute for x==1, *and* x==0, because there was no break statement
    break;

case 2:
    // Code here will execute for x==2 only, because the previous case block ended with a break
}

Answer 2

你忘了在案例陈述的最后放置休息，所以案例（1）继续到案例（3）。

使用java无法实现预期结果，但使用c＃是

2 个答案: