C++ //练习 15.15 定义你自己的Disc_quote和Bulk

C++ //练习 15.15 定义你自己的Disc_quote和Bulk_quote。

C++ Primer（第5版）练习 15.15

练习 15.15 定义你自己的Disc_quote和Bulk_quote。

环境：Linux Ubuntu（云服务器）

工具：vim

代码块

/*************************************************************************> File Name: ex15.15.cpp> Author: > Mail: > Created Time: Fri 12 Jul 2024 09:13:44 AM CST************************************************************************/#include<iostream>
using namespace std;class Quote{public:Quote() = default;Quote(const std::string &book, double sales_price): bookNo(book), price(sales_price) {}std::string isbn() const { return bookNo; }virtual double net_price(std::size_t n) const { return n * price; }virtual ~Quote() = default;private:std::string bookNo;protected:double price = 0.0;
};class Disc_quote: public Quote{public:Disc_quote() = default;Disc_quote(const std::string &book, double price, std::size_t qty, double disc): Quote(book, price), quantity(qty), discount(disc) {}double net_price(std::size_t) const = 0;protected:std::size_t quantity = 0;double discount = 0.0;
};class Bulk_quote: public Disc_quote{public:Bulk_quote() = default;Bulk_quote(const std::string& book, double price, std::size_t qty, double disc): Disc_quote(book, price, qty, disc) {}double net_price(std::size_t) const override;
};double Bulk_quote::net_price(size_t cnt) const{if (cnt >= quantity){return cnt * (1 - discount) * price;}else{return cnt * price;}
}double print_total(ostream &os, const Quote &item, size_t n){double ret = item.net_price(n);os<<"ISBN: "<<item.isbn()<<" # sold: "<<n<<" total due: "<<ret<<endl;return ret;
}int main(){Bulk_quote bulk("1-201-Y-12333", 10, 10, 0.5);print_total(cout, bulk, 20);return 0;
}