写一个彩票程序：随机生成9个随机数（100~999之间）模拟该期彩票号码，不能重复，存入集合中。从键盘输入3个数模拟用户购买号码。

package com.wr.demo;

import java.util.HashSet;

import java.util.Random;

import java.util.Scanner;

import java.util.Set;

public class test06 {

    public static void main(String[] args) {

        Set<Integer> lotteryNumbers = RanLotteryNumbers();

        Set<Integer> userNumbers = getUserNumbers();

        int matchedCount = MatchedNumbers(lotteryNumbers, userNumbers);

        System.out.println("本期彩票号码是：" + lotteryNumbers);

        System.out.println("用户购买的号码是：" + userNumbers);

        System.out.println("中了" + matchedCount + "个号");

        if (matchedCount == 3) {

            System.out.println("恭喜中了一等奖！");

        } else if (matchedCount == 2) {

            System.out.println("恭喜中了二等奖！");

        } else if (matchedCount == 1) {

            System.out.println("恭喜中了三等奖！");

        } else {

            System.out.println("很遗憾，未中奖！");

        }

    }

    private static Set<Integer> RanLotteryNumbers() { //随机生成三个号码

        Set<Integer> lotteryNumbers = new HashSet<>();

        Random random = new Random();

        while (lotteryNumbers.size() < 9) {

            int number = random.nextInt(900) + 100;

            lotteryNumbers.add(number);

        }

        return lotteryNumbers;

    }

    private static Set<Integer> getUserNumbers() {   //获取购买的号码

        Set<Integer> userNumbers = new HashSet<>();

        Scanner scanner = new Scanner(System.in);

        System.out.println("请输入您购买的号码（3个不重复的三位数，以空格分隔）：");

        while (userNumbers.size() < 3) {

            int number = scanner.nextInt();

            if (number >= 100 && number <= 999) {

                userNumbers.add(number);

            } else {

                System.out.println("请输入有效的三位数！");

            }

        }

        return userNumbers;

    }

    private static int MatchedNumbers(Set<Integer> lotteryNumbers, Set<Integer> userNumbers) {

        int count = 0;

        for (int number : userNumbers) {

            if (lotteryNumbers.contains(number)) {

                count++;

            }

        }

        return count;

    }

}

实验运行截图：