// 最优价钱.cpp : Defines the entry point for the console application.

 //

 #include "stdafx.h"

 #include "iostream.h"

 #define PRICE 8

 double discount[]={,0.05,0.1,0.2,0.25};

 double Caculate(int num1,int num2)        //计算该情况的价钱

 {

     double money,money1,money2;

     money1=(PRICE-PRICE*discount[num1-])*num1;

     money2=(PRICE-PRICE*discount[num2-])*num2;

     money=money1+money2;

     return money;

 }

 double Discount(int num)            //分情况讨论价钱

 {

     int k,yushu;

     double money1,money2,min;

     k=num/;                    //取整

     yushu=num%;                //取余

     min=num*PRICE;

     switch(k)

     {

         case :

             money1=(PRICE-PRICE*discount[num-])*num;

             break;

         default:

             if(yushu==)

             {

                 money1=(PRICE-PRICE*discount[])*num;

                 return money1;

             }

             for(int i=;i<(yushu+);i++)

             {

                 money1=Caculate(i,(yushu+)-i);

                 if(money1<min)

                     min=money1;

             }

             if(num>)

                 money2=(k-)**(PRICE-PRICE*discount[]);

             else

                 money2=;

             return min+money2;

     }

     return money1;

 }

 int main(int argc, char* argv[])

 {

     int booknum;

     double money;

     cout<<"请输入购买书籍的数量：";

     cin>>booknum;

     money=Discount(booknum);

     cout<<"最优惠的价格是"<<money<<"元"<<endl;

     return ;

 }