#include "../inc/class_.h"
#include <iostream>
using namespace std;
void dealSales()
{
 //保存当前求和结果的变量
 Sales_data total;
 //读入第一笔交易
 if (read(cin, total))
 {
 //保存下一条交易数据的变量
 Sales_data trans;
 //读入下一条交易数据
 while (read(cin, trans))
 {
 //判断isbn
 if (total.isbn() == trans.isbn())
 {
 //更新变量total的值
 total.combine(trans);
 }
 else
 {
 //输出结果
 print(cout, total) << endl;
 // isbn号不一样,说明是新类型的书
 // 处理新类型的书
 total = trans;
 }
 }
 //输出最后一条交易
 print(cout, total) << endl;
 }
 else
 {
 //没有输出任何信息
 cerr << "No data?!" << endl;
 }
}

double Sales_data::avg_price() const
{
 if (units_sold)
 return revenue / units_sold;
 else
 return 0;
}

Sales_data::Sales_data(const Sales_data &sa)
{
 this->bookNo = sa.bookNo;
 this->revenue = sa.revenue;
 this->units_sold = sa.units_sold;
}

Sales_data::Sales_data(std::istream &is)
{
 read(is, *this);
}

Sales_data &Sales_data::combine(const Sales_data &sa)
{
 this->units_sold += sa.units_sold;
 this->revenue += sa.revenue;
 //返回调用该函数的对象
 return *this;
}

Sales_data add(const Sales_data &sa1, const Sales_data &sa2)
{
 Sales_data total = sa1;
 total.combine(sa2);
 return total;
}

std::ostream &print(std::ostream &os, const Sales_data &item)
{
 os << item.isbn() << " " << item.units_sold << " "
 << item.revenue << " " << item.avg_price();
 return os;
}

std::istream &read(std::istream &is, Sales_data &item)
{
 double price = 0;
 is >> item.bookNo >> item.units_sold >> price;
 return is;
}

std::istream &read(std::istream &is, Sales_new &item)
{
 double price = 0;
 is >> item.bookNo >> item.units_sold >> price;
 return is;
}