C++primer 15.8节练习

  1 #include <iostream>
  2 #include <string>
  3 #include <utility>
  4 #include <memory>
  5 #include <vector>
  6 
  7 using namespace std;
  8 
  9 class Quote {
 10 public:
 11     Quote() : bookNo(""), price(0.0) { cout << "默认构造函数" << endl; }
 12     Quote(const string &book, double sales_price) : bookNo(book), price(sales_price) { cout << "构造函数"<< endl; }
 13     Quote(const Quote& q) : bookNo(q.bookNo), price(q.price) { cout << "拷贝构造函数" << endl; }
 14     Quote(Quote &&q) noexcept : bookNo(q.bookNo), price(q.price) { cout << "移动构造函数" << endl; }
 15     Quote& operator=(const Quote& rhs);
 16     Quote& operator=(Quote&& rhs) noexcept;
 17     const string& isbn() const { return bookNo; }
 18     virtual double net_price(size_t n) const { return n * price; }
 19     virtual ~Quote() = default;
 20 private:
 21     string bookNo;
 22 protected:
 23     double price = 0.0;
 24 };
 25 
 26 class Disc_quote : public Quote {
 27 public:
 28     Disc_quote() : Quote() { cout << "派生类默认构造函数" << endl; }
 29     Disc_quote(const string &book, double sales_price, size_t quan, double dis) : Quote(book, sales_price), quantity(quan), discount(dis) { cout << "派生类构造函数" <<endl; }
 30     Disc_quote(const Disc_quote& d) : Quote(d), quantity(d.quantity), discount(d.discount) { cout << "派生类拷贝构造函数" <<endl; }
 31     Disc_quote(Disc_quote&& d) : Quote(std::move(d)), quantity(d.quantity), discount(d.discount) { cout << "派生类移动构造函数" << endl; }
 32     Disc_quote& operator=(const Disc_quote& rhs);
 33     Disc_quote& operator=(Disc_quote&& rhs);
 34     double net_price(size_t n) const override;
 35     ~Disc_quote() { cout << "派生类析构函数" << endl; }
 36 protected:
 37     size_t quantity = 0;
 38     double discount = 0.0;
 39 };
 40 
 41 class Bulk_quote : public Disc_quote {
 42 public:
 43     Bulk_quote() = default;
 44     Bulk_quote(const string& book, double p, size_t qty, double disc) : Disc_quote(book, p, qty, disc) {}
 45     double net_price(size_t n) const override;
 46 };
 47 
 48 class lim_discount : public Disc_quote {
 49 public:
 50     using Disc_quote::Disc_quote;
 51     double net_price(size_t n) const override;
 52 };
 53 
 54 double print_total(ostream& os, const Quote& item, size_t t);
 55 
 56 int main()
 57 {
 58     vector<shared_ptr<Quote>> basket;
 59     basket.push_back(make_shared<Quote>("C++ primer", 128.00));
 60     basket.push_back(make_shared<Bulk_quote>("C++ plus", 135.2, 15, 0.6));
 61     Bulk_quote b1("C plus", 102.3, 10, 0.9);
 62     basket.push_back(make_shared<Bulk_quote>(b1));
 63     cout << basket.back()->net_price(15) << endl;
 64     system("pause");
 65     return 0;
 66 }
 67 
 68 double print_total(ostream & os, const Quote &item, size_t t)
 69 {
 70     double ret = item.net_price(t);
 71     os << "ISBN: " << item.isbn() << " # sold: " << t << " total due: " << ret << endl;
 72     return ret;
 73 }
 74 
 75 double Bulk_quote::net_price(size_t n) const
 76 {
 77     if (n >= quantity)
 78         return n * (1 - discount) * price;
 79     else
 80         return n * price;
 81 }
 82 
 83 double lim_discount::net_price(size_t n) const
 84 {
 85     if (n <= quantity)
 86         return n * (1 - discount) * price;
 87     else
 88         return Quote::net_price(n);
 89 }
 90 
 91 Quote & Quote::operator=(const Quote & rhs)
 92 {
 93     bookNo = rhs.bookNo;
 94     price = rhs.price;
 95     cout << "拷贝赋值运算符" << endl;
 96     return *this;
 97     // TODO: 在此处插入 return 语句
 98 }
 99 
100 Quote & Quote::operator=(Quote && rhs) noexcept
101 {
102     bookNo = rhs.bookNo;
103     price = rhs.price;
104     cout << "移动赋值运算符" << endl;
105     return *this;
106     // TODO: 在此处插入 return 语句
107 }
108 
109 Disc_quote & Disc_quote::operator=(const Disc_quote & rhs)
110 {
111     Quote::operator=(rhs);
112     quantity = rhs.quantity;
113     discount = rhs.discount;
114     cout << "派生类的拷贝构造运算符" << endl;
115     return *this;
116     // TODO: 在此处插入 return 语句
117 }
118 
119 Disc_quote & Disc_quote::operator=(Disc_quote && rhs)
120 {
121     Quote::operator=(rhs);
122     quantity = rhs.quantity;
123     discount = rhs.discount;
124     cout << "派生类移动构造运算符" << endl;
125     return *this;
126     // TODO: 在此处插入 return 语句
127 }
128 
129 double Disc_quote::net_price(size_t n) const
130 {
131     if (n >= quantity)
132         return n * (1 - discount) * price;
133     else
134         return n * price;
135 }

  1 #include <iostream>
  2 #include <string>
  3 #include <utility>
  4 #include <memory>
  5 #include <vector>
  6 
  7 using namespace std;
  8 
  9 class Quote {
 10 public:
 11     Quote() : bookNo(""), price(0.0) { cout << "默认构造函数" << endl; }
 12     Quote(const string &book, double sales_price) : bookNo(book), price(sales_price) { cout << "构造函数"<< endl; }
 13     Quote(const Quote& q) : bookNo(q.bookNo), price(q.price) { cout << "拷贝构造函数" << endl; }
 14     Quote(Quote &&q) noexcept : bookNo(q.bookNo), price(q.price) { cout << "移动构造函数" << endl; }
 15     Quote& operator=(const Quote& rhs);
 16     Quote& operator=(Quote&& rhs) noexcept;
 17     const string& isbn() const { return bookNo; }
 18     virtual double net_price(size_t n) const { return n * price; }
 19     virtual ~Quote() = default;
 20 private:
 21     string bookNo;
 22 protected:
 23     double price = 0.0;
 24 };
 25 
 26 class Disc_quote : public Quote {
 27 public:
 28     Disc_quote() : Quote() { cout << "派生类默认构造函数" << endl; }
 29     Disc_quote(const string &book, double sales_price, size_t quan, double dis) : Quote(book, sales_price), quantity(quan), discount(dis) { cout << "派生类构造函数" <<endl; }
 30     Disc_quote(const Disc_quote& d) : Quote(d), quantity(d.quantity), discount(d.discount) { cout << "派生类拷贝构造函数" <<endl; }
 31     Disc_quote(Disc_quote&& d) : Quote(std::move(d)), quantity(d.quantity), discount(d.discount) { cout << "派生类移动构造函数" << endl; }
 32     Disc_quote& operator=(const Disc_quote& rhs);
 33     Disc_quote& operator=(Disc_quote&& rhs);
 34     double net_price(size_t n) const override;
 35     ~Disc_quote() { cout << "派生类析构函数" << endl; }
 36 protected:
 37     size_t quantity = 0;
 38     double discount = 0.0;
 39 };
 40 
 41 class Bulk_quote : public Disc_quote {
 42 public:
 43     Bulk_quote() = default;
 44     Bulk_quote(const string& book, double p, size_t qty, double disc) : Disc_quote(book, p, qty, disc) {}
 45     double net_price(size_t n) const override;
 46 };
 47 
 48 class lim_discount : public Disc_quote {
 49 public:
 50     using Disc_quote::Disc_quote;
 51     double net_price(size_t n) const override;
 52 };
 53 
 54 double print_total(ostream& os, const Quote& item, size_t t);
 55 
 56 int main()
 57 {
 58     /*vector<shared_ptr<Quote>> basket;
 59     basket.push_back(make_shared<Quote>("C++ primer", 128.00));
 60     basket.push_back(make_shared<Bulk_quote>("C++ plus", 135.2, 15, 0.6));
 61     Bulk_quote b1("C plus", 102.3, 10, 0.9);
 62     basket.push_back(make_shared<Bulk_quote>(b1));
 63     cout << basket.back()->net_price(15) << endl;*/
 64     vector<Quote> basket;
 65     basket.push_back(Quote("C++ primer", 128.2));
 66     basket.push_back(Bulk_quote("C plus", 102.3, 10, 0.9));
 67     cout << basket.back().net_price(15) << endl;
 68     system("pause");
 69     return 0;
 70 }
 71 
 72 double print_total(ostream & os, const Quote &item, size_t t)
 73 {
 74     double ret = item.net_price(t);
 75     os << "ISBN: " << item.isbn() << " # sold: " << t << " total due: " << ret << endl;
 76     return ret;
 77 }
 78 
 79 double Bulk_quote::net_price(size_t n) const
 80 {
 81     if (n >= quantity)
 82         return n * (1 - discount) * price;
 83     else
 84         return n * price;
 85 }
 86 
 87 double lim_discount::net_price(size_t n) const
 88 {
 89     if (n <= quantity)
 90         return n * (1 - discount) * price;
 91     else
 92         return Quote::net_price(n);
 93 }
 94 
 95 Quote & Quote::operator=(const Quote & rhs)
 96 {
 97     bookNo = rhs.bookNo;
 98     price = rhs.price;
 99     cout << "拷贝赋值运算符" << endl;
100     return *this;
101     // TODO: 在此处插入 return 语句
102 }
103 
104 Quote & Quote::operator=(Quote && rhs) noexcept
105 {
106     bookNo = rhs.bookNo;
107     price = rhs.price;
108     cout << "移动赋值运算符" << endl;
109     return *this;
110     // TODO: 在此处插入 return 语句
111 }
112 
113 Disc_quote & Disc_quote::operator=(const Disc_quote & rhs)
114 {
115     Quote::operator=(rhs);
116     quantity = rhs.quantity;
117     discount = rhs.discount;
118     cout << "派生类的拷贝构造运算符" << endl;
119     return *this;
120     // TODO: 在此处插入 return 语句
121 }
122 
123 Disc_quote & Disc_quote::operator=(Disc_quote && rhs)
124 {
125     Quote::operator=(rhs);
126     quantity = rhs.quantity;
127     discount = rhs.discount;
128     cout << "派生类移动构造运算符" << endl;
129     return *this;
130     // TODO: 在此处插入 return 语句
131 }
132 
133 double Disc_quote::net_price(size_t n) const
134 {
135     if (n >= quantity)
136         return n * (1 - discount) * price;
137     else
138         return n * price;
139 }