实验二 类和对象_基础编程1

1.实验任务一

t.h

#pragma once

#include <string>

// 类T: 声明
class T {
// 对象属性、方法
public:
    T(int x = 0, int y = 0);   // 普通构造函数
    T(const T &t);  // 复制构造函数
    T(T &&t);       // 移动构造函数
    ~T();           // 析构函数

    void adjust(int ratio);      // 按系数成倍调整数据
    void display() const;           // 以(m1, m2)形式显示T类对象信息

private:
    int m1, m2;

// 类属性、方法
public:
    static int get_cnt();          // 显示当前T类对象总数

public:
    static const std::string doc;       // 类T的描述信息
    static const int max_cnt;           // 类T对象上限

private:
    static int cnt;         // 当前T类对象数目

// 类T友元函数声明
    friend void func();
};

// 普通函数声明
void func();

t.cpp

// 类T: 实现
// 普通函数实现

#include "t.h"
#include <iostream>
#include <string>

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

// static成员数据类外初始化
const std::string T::doc{"a simple class sample"};
const int T::max_cnt = 999;
int T::cnt = 0;


// 对象方法
T::T(int x, int y): m1{x}, m2{y} { 
    ++cnt; 
    cout << "T constructor called.\n";
} 

T::T(const T &t): m1{t.m1}, m2{t.m2} {
    ++cnt;
    cout << "T copy constructor called.\n";
}

T::T(T &&t): m1{t.m1}, m2{t.m2} {
    ++cnt;
    cout << "T move constructor called.\n";
}    

T::~T() {
    --cnt;
    cout << "T destructor called.\n";
}           

void T::adjust(int ratio) {
    m1 *= ratio;
    m2 *= ratio;
}    

void T::display() const {
    cout << "(" << m1 << ", " << m2 << ")" ;
}     

// 类方法
int T::get_cnt() {
   return cnt;
}

// 友元
void func() {
    T t5(42);
    t5.m2 = 2049;
    cout << "t5 = "; t5.display(); cout << endl;
}

运行结果截图：

问题一：
　　　　line36可以删除，程序正常运行。

 

问题二：构造函数用于初始化对象的成员变量。

　　　　复制构造函数用于创建一个新对象，该对象是现有对象副本

　　　　移动构造函数允许资源从一个对象转移到另一个对象，而不进行复制。

　　　　析构函数用于在对象生命周期结束时执行清理工作

调用时机：
　　　　构造函数：在创建对象时调用

　　　　复制构造函数：在需要创建一个对象的副本调用

　　　　移动构造函数：在需要将一个右值对象的资源转移到新对象

　　　　析构函数：在对象生命周期结束时调用

 

问题三：

　　　　t.cpp中，line13-15，调整到t.h，重新编译，程序能正确编译运行。

 

2.实验任务二

Complex.h

#pragma once
#include<string>
class Complex{
    public:
        Complex();
        Complex(double re);
        Complex(double re,double im);
        Complex(const Complex &c );
        double get_real() const;
        double get_imag() const; 
        void add(const Complex &c);

        friend Complex add(const Complex &c1,const Complex &c2);
        friend bool is_equal(const Complex &c1,const Complex &c2);
        friend bool is_not_equal(const Complex &c1,const Complex &c2);
        friend void output(const Complex &c);
        friend double abs(const Complex &c);
    
        public:
                static const std::string doc;       
               
        private:
            double real,imag;
};
     Complex add(const Complex &c1,const Complex &c2);
         bool is_equal(const Complex &c1,const Complex &c2);
         bool is_not_equal(const Complex &c1,const Complex &c2);
         void output(const Complex &c);
         double abs(const Complex &c);

Complex.cpp

#include <iostream>
#include "Complex.h"
#include<cmath>
using namespace std;
const string Complex::doc{"a simplified complex class"};

Complex::Complex() : real(0), imag(0) {}

Complex::Complex(double re) : real(re), imag(0) {}

Complex::Complex(double re, double im) : real(re), imag(im) {}

Complex::Complex(const Complex& other) : real(other.real), imag(other.imag) {}

double Complex::get_real() const { return real; }

double Complex::get_imag() const { return imag; }

void Complex::add(const Complex& other) {
    real += other.real;
    imag += other.imag;
}

Complex add(const Complex& c1, const Complex& c2) {
    return Complex(c1.get_real() + c2.get_real(), c1.get_imag() + c2.get_imag());
}

bool is_equal(const Complex& c1, const Complex& c2) {
    return (c1.get_real() == c2.get_real()) && (c1.get_imag() == c2.get_imag());
}

bool is_not_equal(const Complex& c1, const Complex& c2) {
    return !is_equal(c1, c2);
}

void output(const Complex& c) {
    std::cout << c.get_real() << " + " << c.get_imag() << "i" << std::endl;
}

double abs(const Complex& c) {
    return std::sqrt(c.get_real() * c.get_real() + c.get_imag() * c.get_imag());
}

task2.cpp

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

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

void test() {
    cout << "类成员测试: " << endl;
    cout << Complex::doc << endl;

    cout << endl;

    cout << "Complex对象测试: " << endl;
    Complex c1;
    Complex c2(3, -4);
    const Complex c3(3.5);
    Complex c4(c3);

    cout << "c1 = "; output(c1); cout << endl;
    cout << "c2 = "; output(c2); cout << endl;
    cout << "c3 = "; output(c3); cout << endl;
    cout << "c4 = "; output(c4); cout << endl;
    cout << "c4.real = " << c4.get_real() << ", c4.imag = " << c4.get_imag() << endl;

    cout << endl;

    cout << "复数运算测试: " << endl;
    cout << "abs(c2) = " << abs(c2) << endl;
    c1.add(c2);
    cout << "c1 += c2, c1 = "; output(c1); cout << endl;
    cout << boolalpha;
    cout << "c1 == c2 : " << is_equal(c1, c2) << endl;
    cout << "c1 != c3 : " << is_not_equal(c1, c3) << endl;
    c4 = add(c2, c3);
    cout << "c4 = c2 + c3, c4 = "; output(c4); cout << endl;
}

int main() {
    test();
}

运行结果测试：

3.实验任务三

#include <iostream>
#include <complex>

using std::cout;
using std::endl;
using std::boolalpha;
using std::complex;

void test() {
    cout << "标准库模板类comple测试: " << endl;
    complex<double> c1;
    complex<double> c2(3, -4);
    const complex<double> c3(3.5);
    complex<double> c4(c3);

    cout << "c1 = " << c1 << endl;
    cout << "c2 = " << c2 << endl;
    cout << "c3 = " << c3 << endl;
    cout << "c4 = " << c4 << endl;
    cout << "c4.real = " << c4.real() << ", c4.imag = " << c4.imag() << endl;
    cout << endl;

    cout << "复数运算测试: " << endl;
    cout << "abs(c2) = " << abs(c2) << endl;
    c1 += c2;
    cout << "c1 += c2, c1 = " << c1 << endl;
    cout << boolalpha;
    cout << "c1 == c2 : " << (c1 == c2) << endl;
    cout << "c1 != c3 : " << (c1 != c3) << endl;
    c4 = c2 + c3;
    cout << "c4 = c2 + c3, c4 = " << c4 << endl;
}

int main() {
    test();
}

运行结果截图：

4.实验任务四

Fraction.h

#pragma once
#include<string>

using std::string;
class  Fraction {
 public:
        static const string doc;
    public:
        Fraction(int u,int d=1);
        Fraction(const Fraction &f);

    public:
        int get_up() const;
        int get_down() const;
        Fraction negative();
        Fraction simplify();


    private:
        int up;
        int down;


    private:
        friend void  output(const Fraction &f);
        friend Fraction add(const Fraction &f1,const Fraction &f2);
        friend Fraction sub(const Fraction &f1,const Fraction &f2);
        friend Fraction mul(const Fraction &f1,const Fraction &f2);
        friend Fraction div(const Fraction &f1,const Fraction &f2);

};

void output(const Fraction& f1);
Fraction add(const Fraction& f1, const Fraction& f2);
Fraction sub(const Fraction& f1, const Fraction& f2);
Fraction mul(const Fraction& f1, const Fraction& f2);
Fraction div(const Fraction& f1, const Fraction& f2);

Fraction.cpp

#include <iostream>
#include <string>
#include "Fraction.h"

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

const string Fraction::doc{
    "Fraction类 v 0.01版. 目前仅支持分数对象的构造、输出、加/减/乘/除运算."
};

Fraction::Fraction(int u,int d):up{u},down{d}{}
Fraction::Fraction(const Fraction &f):up{f.up},down{f.down}{}



int Fraction::get_up() const{
    return up;
}

int Fraction::get_down() const{
    return down;
}

Fraction Fraction::negative() {
    Fraction f = simplify();
    return Fraction(-f.up,f.down);
}

Fraction Fraction::simplify()
{
    int min,u,d,k;
    if (up >= 0)
    {
        u= up;
        if (down > 0)
        {
            d=down;
            k= 1;
        }
        else
        {
            d= -down;
            k = -1;
        }
    }
    else
    {
        u= -up;
        if (down > 0)
        {
            d = down;
            k = -1;
        }
        else
        {
            d= -down;
            k = 1;
        }
    }
    if (u>d)
        min=d;
    else
        min=u;
    for (int t = min; t >= 1; t--)
        if (u%t==0&&d%t == 0)
        {
            u=u/t;
            d=d/t;
            break;
        }
    if (k== 1)
        return Fraction(u, d);
    return Fraction(-u, d);
}

void output(const Fraction& f){
    Fraction t = Fraction(f.up,f.down);
    t = t.simplify();
    if(t.down == 0) cout << "分母不能为0";
    else {
        if(t.up == 0)
        cout << "0";
    else if(t.up != 0 && t.down == 1)
        cout << t.up;
    else
         cout << t.up << "/" << t.down;
    cout << endl;
    }
}
Fraction add(const Fraction &f1,const Fraction &f2) {
    return Fraction(f1.up * f2.down + f2.up * f1.down, f1.down * f2.down);
}
Fraction sub(const Fraction &f1,const Fraction &f2) {
    return Fraction(f1.up * f2.down - f2.up * f1.down,f1.down * f2.down);
}
Fraction mul(const Fraction &f1,const Fraction &f2) {
    return Fraction(f1.up*f2.up,f1.down*f2.down);

}
Fraction div(const Fraction &f1,const Fraction &f2) {
    return Fraction(f1.up*f2.down,f1.down*f2.up);

}

task4.cpp

#include "Fraction.h"
#include <iostream>

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


void test1() {
    cout << "Fraction类测试: " << endl;
    cout << Fraction::doc << endl << endl;

    Fraction f1(5);
    Fraction f2(3, -4), f3(-18, 12);
    Fraction f4(f3);
    cout << "f1 = "; output(f1); cout << endl;
    cout << "f2 = "; output(f2); cout << endl;
    cout << "f3 = "; output(f3); cout << endl;
    cout << "f4 = "; output(f4); cout << endl;

    Fraction f5(f4.negative());
    cout << "f5 = "; output(f5); cout << endl;
    cout << "f5.get_up() = " << f5.get_up() << ", f5.get_down() = " << f5.get_down() << endl;

    cout << "f1 + f2 = "; output(add(f1, f2)); cout << endl;
    cout << "f1 - f2 = "; output(sub(f1, f2)); cout << endl;
    cout << "f1 * f2 = "; output(mul(f1, f2)); cout << endl;
    cout << "f1 / f2 = "; output(div(f1, f2)); cout << endl;
    cout << "f4 + f5 = "; output(add(f4, f5)); cout << endl;
}

void test2() {
    Fraction f6(42, 55), f7(0, 3);
    cout << "f6 = "; output(f6); cout << endl;
    cout << "f7 = "; output(f7); cout << endl;
    cout << "f6 / f7 = "; output(div(f6, f7)); cout << endl;
}

int main() {
    cout << "测试1: Fraction类基础功能测试\n";
    test1();

    cout << "\n测试2: 分母为0测试: \n";
    test2();
}

运行结果测试：

 5、实验任务五

account.h

#pragma once
#ifndef  ACCOUNT_H
#define  ACCOUNT_H
class SavingsAccount {
    private:
        int id;
        double balance;
        double rate;
        int lastDate;
        double accumulation;
        static double total;

        void record(int date, double amount);
        double accumulate(int date)const {
            return accumulation + balance * (date - lastDate);
        }


    public:
        SavingsAccount(int date, int id, double rate);
        int getId()const {
            return id;
        }
        double getBanlance()const {
            return balance;
        }
        double getRate()const {
            return rate;
        }
        static double getTotal() {
            return total;
        }
        void deposit(int date, double amcount);
        void withdraw(int date, double amount);
        void settle(int date);
        void show()const;
};
#endif

account.cpp

#include"account.h"
#include<cmath>
#include<iostream>
using namespace std;
double SavingsAccount::total = 0;
SavingsAccount::SavingsAccount(int date, int id, double rate):id(id), balance(0), rate(rate), lastDate(date), accumulation(0) {
    cout << date << "\t#" << id << " is created" << endl;
}

void SavingsAccount::record(int date, double amount) {
    accumulation = accumulate(date);
    lastDate = date;
    amount = floor(amount * 100 + 0.5) / 100;
    balance += amount;
    total += amount;
    cout << date << "\t#" << id << "\t" << amount << "\t" << balance << endl;
}

void SavingsAccount::deposit(int date, double amount) {
    record(date, amount);
}

void SavingsAccount::withdraw(int date, double amount) {
    if (amount > getBanlance())
        cout << "Error: not enough money" << endl;
    else
        record(date, -amount);
}

void SavingsAccount::settle(int date) {
    double interest = accumulate(date) * rate / 365;
    if (interest != 0)
        record(date, interest);
    accumulation = 0;
}

void SavingsAccount::show()const {
    cout << "#" << id << "\tBalance:" << balance;
}

task5.cpp

#include"account.h"
#include<iostream>
using namespace std;
int main() {
    SavingsAccount sa0(1, 21325302, 0.015);
    SavingsAccount sa1(1, 58320212, 0.015);

    sa0.deposit(5, 5000);
    sa1.deposit(25, 10000);
    sa0.deposit(45, 5500);
    sa1.withdraw(60, 4000);

    sa0.settle(90);
    sa1.settle(90);

    sa0.show(); cout << endl;
    sa1.show(); cout << endl;
    cout << "Total:" << SavingsAccount::getTotal() << endl;
    return 0;
}

运行结果测试：