实验5

任务1

publisher.hpp

#pragma once

#include <iostream>
#include <string>

using std::cout;
using std::endl;
using std::string;

// 发行/出版物类：Publisher （抽象类）
class Publisher {
public:
    Publisher(const string &s = "");            // 构造函数

public:
    virtual void publish() const = 0;                 // 纯虚函数，作为接口继承
    virtual void use() const = 0;                     // 纯虚函数，作为接口继承

protected:
    string name;    // 发行/出版物名称
};

Publisher::Publisher(const string &s): name {s} {
}


// 图书类: Book
class Book: public Publisher {
public:
    Book(const string &s = "", const string &a = "");  // 构造函数

public:
    void publish() const override;        // 接口
    void use() const override;            // 接口

private:
    string author;          // 作者
};

Book::Book(const string &s, const string &a): Publisher{s}, author{a} {
}

void Book::publish() const {
    cout << "Publishing book: 《" << name << "》 by " << author << endl;
}

void Book::use() const {
    cout << "Reading book: " << name << " by " << author << endl;
}


// 电影类: Film
class Film: public Publisher {
public:
    Film(const string &s = "", const string &d = "");   // 构造函数

public:
    void publish() const override;    // 接口
    void use() const override;        // 接口            

private:
    string director;        // 导演
};

Film::Film(const string &s, const string &d): Publisher{s}, director{d} {
}

void Film::publish() const {
    cout << "Publishing film: <" << name << "> directed by " << director << endl;
}

void Film::use() const {
    cout << "Watching film: " << name << " directed by " << director << endl;
}


// 音乐类：Music
class Music: public Publisher {
public:
    Music(const string &s = "", const string &a = "");

public:
    void publish() const override;        // 接口
    void use() const override;            // 接口

private:
    string artist;      // 音乐艺术家名称
};

Music::Music(const string &s, const string &a): Publisher{s}, artist{a} {
}

void Music::publish() const {
    cout << "Publishing music <" << name << "> by " << artist << endl;
}

void Music::use() const {
    cout << "Listening to music: " << name << " by " << artist << endl;
}

task.cpp

#include "publisher.hpp"
#include <vector>
#include <typeinfo>

using std::vector;

void test() {
   vector<Publisher *> v;

   v.push_back(new Book("Harry Potter", "J.K. Rowling"));
   v.push_back(new Film("The Godfather", "Francis Ford Coppola"));
   v.push_back(new Music("Blowing in the wind", "Bob Dylan"));

   for(auto &ptr: v) {
        cout << "pointer type: " << typeid(ptr).name() << endl;  // 输出指针类型
        cout << "RTTI type: " << typeid(*ptr).name() << endl;    // 输出指针指向的对象类型
        ptr->publish();
        ptr->use();
        cout << endl;
   }
}

int main() {
    test();
}

任务2

book.hpp

#pragma once

#include <string>
#include <iostream>
#include <iomanip>

using std::string;
using std::ostream;
using std::endl;
using std::setw;
using std::left;

class Book {
public:
    Book(const string &name, const string &author, const string &translator, const string &isbn, float price);

    friend ostream& operator<<(ostream &out, const Book &book);

private:
    string name;        // 书名
    string author;      // 作者
    string translator;  // 译者
    string isbn;        // isbn号
    float price;        // 定价
};

// 成员函数实现
Book::Book(const string &name, const string &author, const string &translator, const string &isbn, float price) {
    this->name = name;
    this->author = author;
    this->translator = translator;
    this->isbn = isbn;
    this->price = price;
}

// 友元实现
ostream& operator<<(ostream &out, const Book &book) {
    out << left;
    out << setw(15) << "书名:" << book.name << endl
        << setw(15) << "作者:" << book.author << endl
        << setw(15) << "译者:" << book.translator << endl
        << setw(15) << "ISBN:" << book.isbn << endl
        << setw(15) << "定价:" << book.price;

    return out;
}

booksale.hpp

#pragma once

#include "book.hpp"
#include <iostream>
#include <string>
#include <iomanip>

using std::string;
using std::cout;
using std::endl;
using std::setw;

class BookSale {
public:
    BookSale(const Book &b, float price, int amount);
    int get_amount() const;
    
    friend ostream& operator<<(ostream &out, const BookSale &item);

private:
    Book rb;         
    float sales_price;      // 售价
    int sales_amount;       // 销售数量
    float revenue;          // 营收
};

// 成员函数实现
BookSale::BookSale(const Book &b, float price, int amount): rb{b}, sales_price(price), sales_amount{amount} {  
    revenue = sales_amount * sales_price;
}

int BookSale::get_amount() const {
    return sales_amount;
}

// 友元函数实现
ostream& operator<<(ostream &out, const BookSale &item) {
    out << left;
    out << item.rb << endl
        << setw(15) << "售价:" << item.sales_price << endl
        << setw(15) << "销售数量:" << item.sales_amount << endl
        << setw(15) << "营收:" << item.revenue;

    return out;
}

task.cpp

#include "booksale.hpp"
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>

// 按图书销售数额比较
bool compare_by_amount(const BookSale &x1, const BookSale &x2) {
    return x1.get_amount() > x2.get_amount();
}

void test() {
    using namespace std;

     vector<BookSale> sales_lst;         // 存放图书销售记录

     int books_number;
    cout << "录入图书数量: ";
    cin >> books_number;

    cout << "录入图书销售记录" << endl;
    for(int i = 0; i < books_number; ++i) {
        string name, author, translator, isbn;
        float price;
        cout << string(20, '-') << "第" << i+1 << "本图书信息录入" << string(20, '-') << endl;
        cout << "录入书名: "; cin >> name;
        cout << "录入作者: "; cin >> author;
        cout << "录入译者: "; cin >> translator;
        cout << "录入isbn: "; cin >> isbn;
        cout << "录入定价: "; cin >> price;

        Book book(name, author, translator, isbn, price);

        float sales_price;
        int sales_amount;

        cout << "录入售价: "; cin >> sales_price;
        cout << "录入销售数量: "; cin >> sales_amount;

        BookSale record(book, sales_price, sales_amount);
        sales_lst.push_back(record);
    }

    // 按销售册数排序
    sort(sales_lst.begin(), sales_lst.end(), compare_by_amount);

    // 按销售册数降序输出图书销售信息
    cout << string(20, '=') <<  "图书销售统计" << string(20, '=') << endl;
    for(auto &t: sales_lst) {
        cout << t << endl;
        cout << string(40, '-') << endl;
    }
}

int main() {
    test();
}

任务3

pets.hpp

#include <string>
#include <iostream>
using namespace std;

class MachinePets {
public:
    virtual ~MachinePets() = default;  
    virtual string get_nickname() const = 0;  
    virtual string talk() const = 0;        
};


class PetCats : public MachinePets {
private:
    string nickname;

public:
    PetCats(const string& name) : nickname(name) {}
    string get_nickname() const override {
        return nickname;
    }
    string talk() const override {
        return "Meow";
    }
};


class PetDogs : public MachinePets {
private:
    string nickname;

public:
    PetDogs(const string& name) : nickname(name) {}
    string get_nickname() const override {
        return nickname;
    }
    string talk() const override {
        return "Woof";
    }
};

task.cpp

#include <iostream>
#include <vector>
#include "pets.hpp"

void test() {
    using namespace std;

    vector<MachinePets *> pets;

    pets.push_back(new PetCats("miku"));
    pets.push_back(new PetDogs("da huang"));

    for(auto &ptr: pets)
        cout <<ptr->get_nickname() << " says " << ptr->talk() << endl;
}

int main() {
    test();
}

任务4

film.hpp

#include <iostream>
#include <string>

using namespace std;

class Film{
    private:
        string title;
        int year;

    public:

        Film(string t="", int y=0):title(t), year(y){}
        int getYear() const { return year; }
        friend istream& operator>>(istream& in, Film& film) {
        cout << "请输入电影标题: ";
        in >> std::ws;
        getline(in, film.title); 
        cout << "请输入发行年份: ";
        in >> film.year;
        
        
        return in;
    }

    friend ostream& operator<<(ostream& out, const Film& film) {
        out << "电影标题: " << film.title << 
             ", 发行年份: " << film.year ;
        return out;
    }
    
};
bool compare_by_year(const Film& f1, const Film& f2) {
    return f1.getYear() < f2.getYear();
}

task.cpp

#include "film.hpp"
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>

void test() {
    using namespace std;
    
    int n;
    cout << "输入电影数目: ";
    cin >> n;

    cout << "录入" << n << "部影片信息" << endl;
    vector<Film> film_lst;
    for(int i = 0; i < n; ++i) {
        Film f;
        cout << string(20, '-') << "第" << i+1 << "部影片录入" << string(20, '-') << endl;
        cin >> f;
        film_lst.push_back(f);
    }

    // 按发行年份升序排序
    sort(film_lst.begin(), film_lst.end(), compare_by_year);

    cout << string(20, '=') + "电影信息(按发行年份)" +  string(20, '=')<< endl;
    for(auto &f: film_lst)
        cout << f << endl;
}

int main() {
    test();
}

任务5

Complex.hpp

#include <iostream>
#include <string>

using namespace std;
template <typename T>
class Complex {
    private:
        T real;
        T imag;
    public:
        Complex(double r = 0, double i = 0): real(r), imag(i) {}
        T get_real () const { return real; }
        T get_imag () const { return imag; }
        Complex operator+(const Complex& other) const {
        return Complex(real + other.real, imag + other.imag);
        }
        Complex& operator+=(const Complex& other) {
        real += other.real;
        imag += other.imag;
        return *this;
        }
        bool operator==(const Complex& other) const {
        return real == other.real && imag == other.imag;
        }
        friend istream& operator>>(istream& in, Complex& c) {
        in >> c.real >> c.imag;
        return in;
    }

    
    friend ostream& operator<<(ostream& out, const Complex& c) {
        out << "(" << c.real << " + " << c.imag << "i)";
        return out;
    }

};

task.cpp

#include "Complex.hpp"
#include <iostream>

using std::cin;
using std::cout;
using std::endl;
using std::boolalpha;

void test1() {
    Complex<int> c1(2, -5), c2(c1);

    cout << "c1 = " << c1 << endl;
    cout << "c2 = " << c2 << endl;
    cout << "c1 + c2 = " << c1 + c2 << endl;
    
    c1 += c2;
    cout << "c1 = " << c1 << endl;
    cout << boolalpha << (c1 == c2) << endl;
}

void test2() {
    Complex<double> c1, c2;
    cout << "Enter c1 and c2: ";
    cin >> c1 >> c2;
    cout << "c1 = " << c1 << endl;
    cout << "c2 = " << c2 << endl;

    cout << "c1.real = " << c1.get_real() << endl;
    cout << "c1.imag = " << c1.get_imag() << endl;
}

int main() {
    cout << "自定义类模板Complex测试1: " << endl;
    test1();

    cout << endl;

    cout << "自定义类模板Complex测试2: " << endl;
    test2();
}

任务6

date.h

//date.h
#ifndef DATE_H
#define DATE_H
class Date {
private:
    int year;
    int month;
    int day;
    int totalDays;
public:
    Date(int year, int month, int day);
    int getYear()const { return year; }
    int getMonth()const { return month; }
    int getDay()const { return day; }
    int getMaxDay()const;
    bool isLeapYear()const {
        return (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0));
    }
    void show()const;
    int operator-(const Date& date)const {
        return totalDays - date.totalDays;
    }
};
#endif // DATE_H

date.cpp

#include"date.h"
#include<iostream>
#include<cstdlib>
using namespace std;
namespace {
    const int DAYS_BEFORE_MONTH[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 };
}
Date::Date(int year, int month, int day) :year(year), month(month), day(day) {
    if (day <= 0 || day > getMaxDay()) {
        cout << "Invalid date!";
        show();
        cout << endl;
        exit(1);
    }
    int years = year - 1;
    totalDays = years * 365 + years / 4 - years / 100 + years / 400 + DAYS_BEFORE_MONTH[month - 1] + day;
    if (isLeapYear() && month > 2)
        totalDays++;
}
int Date::getMaxDay() const {
    if (isLeapYear() && month == 2)
        return 29;
    else
        return DAYS_BEFORE_MONTH[month] - DAYS_BEFORE_MONTH[month - 1];
}
void Date::show() const {
    cout << getYear() << "-" << getMonth() << "-" << getDay();
}

改进：使用了运算符重载，使运算更加简单直观，同时程序修改维护更加方便。

不足：没有实现交互，不能实时。