21.升级我行我素管理系统实现换购的功能

//本代码为测试代码，所以存在错误

//出错的演练，当输入200，case6时不报错。

//等待更新。

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        System.out.println("请输入消费金额");
        Scanner input = new Scanner(System.in);
        Double money = input.nextDouble();
        String buHuanGou = ("很抱歉，您不满足换购要求"); // buHuanGou--当客户换购时，输出空，即为不输出
        System.out
                .println("是否参加换购活动\n1.满50元，加两元换购百事可乐饮料一瓶\n2.满100元，加三元换购500ml百事可乐\n3.满一百元，加10元换购五公斤面粉\n4.满200元，加十元换购一个苏泊尔炒饭锅\n5.满200元，加20元，换购欧莱雅香水爽肤水\n0.不换购\n请选择：");
        int num = input.nextInt();

        if (money >= 100 && money < 200) {

            switch (num) {
            case 0:
                System.out.println("您选择了不换购");
                buHuanGou = "";
                break;
            case 1:
                money = money + 2;
                System.out.println("本次消费为" + money + "\n成功换购" + num);
                buHuanGou = "";
                break;
            case 2:
                money = money + 3;
                System.out.println("本次消费为" + money + "\n成功换购" + num);
                buHuanGou = "";
                break;
            case 3:
                money = money + 10;
                System.out.println("本次消费为" + money + "\n成功换购" + num);
                buHuanGou = "";
                break;
            }

        }
        if (money < 50 && num == 0) {
            buHuanGou = "";
        }
        
        if (money >= 50 && money < 100) {

            switch (num) {
            case 0:
                System.out.println("您选择了不换购");
                buHuanGou = "";
                break;
            case 1:
                money = money + 2;
                System.out.println("本次消费为" + money + "\n成功换购" + num);
                break;

            }

        }

        if (money >= 200) {
            switch (num) {
            case 0:
                System.out.println("您选择了不换购");
                buHuanGou = "";
                break;
            case 1:
                money = money + 2;
                System.out.println("本次消费为" + money + "\n成功换购" + num);
                break;
            case 2:
                money = money + 3;
                System.out.println("本次消费为" + money + "\n成功换购" + num);
                break;
            case 3:
                money = money + 10;
                System.out.println("本次消费为" + money + "\n成功换购" + num);
                break;

            case 4:
                money = money + 10;
                System.out.println("本次消费为" + money + "\n成功换购" + num);
                break;

            case 5:
                money = money + 20;
                System.out.println("本次消费为" + money + "\n成功换购" + num);
                break;
            }
        } else {
            if (num > 5 || num < 0) {
                buHuanGou = "您的输入有误！";
            }
            System.out.println(buHuanGou + "\n感谢您的光临，欢迎再次惠顾！");
        }
        
        
    }
}