黑马 ---- 判断数的存在

卖飞机票
机票价格按照淡季旺季、头等舱和经济舱收费，输入机票原价、月份和头等舱和经济舱
规则：旺季(5-10月)头等舱 9 折、经济舱 8.5 折
淡季(11-4月)头等舱 7 折、经济舱 6.5 折

public static void main(String[] args) {
    Scanner s = new Scanner(System.in);

    System.out.println("请输入原价:");
    int price = s.nextInt();

    System.out.println("请输入月份:");
    int month = s.nextInt();

    System.out.println("请输入位置:");
    String seat = s.next();

    System.out.println("您的新票价是:" + newPrice(price,month,seat));

    s.close();
}

public static double newPrice(int price,int month,String seat){

    double newPrice = 0;

    if(month <= 10 && month >= 5){ //旺季

        switch (seat){
            case "头等舱":
                newPrice = price * 0.9;
                break;
            case "经济舱":
                newPrice = price * 0.85;
                break;
            default:
                System.out.println("座位输入有误！");
                break;
        }

    }else if(month == 11 || month == 12 || (month <= 4 && month >= 1)){ //淡季

        switch (seat){
            case "头等舱":
                newPrice = price * 0.7;
                break;
            case "经济舱":
                newPrice = price * 0.65;
                break;
            default:
                System.out.println("座位输入有误！");
                break;
        }

    }else{
        System.out.println("月份输入有误！");
        return newPrice;
    }

    return newPrice;
}