用java写个概率的抽奖，给出代码

### 回答1：

我可以给你一些示例代码来帮助你编写一个概率抽奖程序：// 生成概率数组
int[] probabilities = {10, 20, 30, 40};// 计算总概率
int total = 0;
for (int probability : probabilities) {
total += probability;
}// 产生随机数
Random random = new Random();
int randomNumber = random.nextInt(total) + 1;// 根据随机数选择奖品
int prize = 0;
int cumulativeProbability = 0;
for (int i = 0; i < probabilities.length; i++) {
cumulativeProbability += probabilities[i];
if (randomNumber <= cumulativeProbability) {
prize = i;
break;
}
}

### 回答2：
下面是使用Java编写的一个简单的概率抽奖的代码示例：

import java.util.ArrayList;
import java.util.List;
import java.util.Random;

public class Lottery {
    private List<String> participants;
    private List<Double> probabilities;
    private Random random;

    public Lottery() {
        participants = new ArrayList<>();
        probabilities = new ArrayList<>();
        random = new Random();
    }

    public void addParticipant(String participant, double probability) {
        participants.add(participant);
        probabilities.add(probability);
    }

    public String drawWinner() {
        double totalProbability = 0;
        for (double probability : probabilities) {
            totalProbability += probability;
        }

        double randomValue = random.nextDouble() * totalProbability;
        double cumulativeProbability = 0;

        for (int i = 0; i < participants.size(); i++) {
            cumulativeProbability += probabilities.get(i);
            if (randomValue <= cumulativeProbability) {
                return participants.get(i);
            }
        }

        return null;
    }

    public static void main(String[] args) {
        Lottery lottery = new Lottery();

        // 添加抽奖参与者和概率
        lottery.addParticipant("张三", 0.2);
        lottery.addParticipant("李四", 0.3);
        lottery.addParticipant("王五", 0.5);

        // 进行一次抽奖
        String winner = lottery.drawWinner();
        System.out.println("恭喜 " + winner + " 中奖了！");
    }
}

这个代码中，`Lottery` 类用于管理抽奖，`addParticipant` 方法用于添加抽奖参与者和对应的中奖概率，`drawWinner` 方法用于进行抽奖操作，返回中奖者的名字。`main` 方法演示了如何使用该抽奖类进行一次抽奖。在这个例子中，有三个参与者，分别对应不同的中奖概率。代码使用随机数生成一个0到总概率之间的值，并根据概率计算中奖者。输出语句会打印中奖者的名字。