Java 小白 图书馆举办双十一买二享五折活动，设计一个打折方法，传入顾客的图书数组，然后重新为图书定价，已知顾客购买的图书为59.8，69.8，在控制台输出打折钱和打折后的图书信息

import java.util.Scanner;

public class BorrowABook
{
    public static void main(String[] args)
    {
        BorrowABook rate = new BorrowABook();
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入价格,用空格隔开");
        double num = sc.nextDouble();
        double num1 = sc.nextDouble();
        double [] a = {num,num1};
        System.out.println("打折前的价格");
        for (int i = 0;i<a.length;i++)
        {
            System.out.println(a[i]+"元");
        }
        rate.chang(a);
        System.out.println("打折后");
        for (int j = 0;j < a.length;j++)
        {
            System.out.println(a[j]+"元");
        }
    }
    public void chang (double[] i)
    {
        for (int j = 0;j<i.length;j++)
        {
            i[j] = i[j] *0.5;
        }
    }
}