软件工程练习——买书

import java.util.*;
import javax.swing.*;
public class Haripoter {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        System.out.println("请输入购买数量（本）：");
        Scanner sca = new Scanner(System.in);
        int  num = sca.nextInt();
        double  price = 0;
        System.out.println("总价为：");
            if(num%8==0)
            {
                price = (num/8)*51.2;
                System.out.println(price+"元");
            }
        
            if(num%8==1)
            {
                price = (num/5)*30+8;
                System.out.println(price+"元");
            }
            if(num%8==2)
            {
                price = (num/5)*30+15.2;
                System.out.println(price+"元");
            }
            if(num%8==3)
            {
                price = (num/5)*30+21.6;
                System.out.println(price+"元");
            }
            if(num%8==4)
            {
                price = (num/5)*30+25.6;
                System.out.println(price+"元");
            }
            if(num%8==5)
            {
                price = (num/5)*30+30;
                System.out.println(price+"元");
            }
            if(num%8==6)
            {
                price = (num/5)*30+38;
                System.out.println(price+"元");
            }
            if(num%8==7)
            {
                price = (num/5)*30+45.2;
                System.out.println(price+"元");
            }
        }
    }