实验2

task1

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;
}

task1.cpp

#include "t.h"
#include <iostream>
using std::cout;
using std::endl;
void test();
int main() {
    test();
    cout << "\nmain: \n";
    cout << "T objects'current count: " << T::get_cnt() << endl;
}
void test() {
    cout << "test class T: \n";
    cout << "T info: " << T::doc << endl;
    cout << "T objects'max count: " << T::max_cnt << endl;
        
        cout << "T objects'current count: " << T::get_cnt() << endl << endl;
    T t1;
    cout << "t1 = "; t1.display(); cout << endl;
    T t2(3, 4);
    cout << "t2 = "; t2.display(); cout << endl;
    T t3(t2);
    t3.adjust(2);
    cout << "t3 = "; t3.display(); cout << endl;
    T t4(std::move(t2));
    cout << "t3 = "; t4.display(); cout << endl;
    cout << "T objects'current count: " << T::get_cnt() << endl;
    func();
}

 question1.

 找不到标识符

question2.

普通构造函数:正常使用

复制构造函数:用于通过一个已存在的对象来创建一个新对象。

移动构造函数:用于通过一个临时对象来创建一个新对象。

析构函数:释放内存。

question3.

不能

 

task2

complex.h

#pragma once
#include <iostream>
#include <cmath>

class Complex {
public:
    Complex(); // 默认构造函数
    Complex(double real, double imag); // 构造函数
    Complex(double real); // 单参构造函数
    Complex(const Complex& other); // 拷贝构造函数

    double get_real() const; // 返回实部
    double get_imag() const; // 返回虚部
    Complex add(const Complex& c);
    friend Complex add(const Complex& c1, const Complex& c2); // 复数相加
    friend bool is_equal(const Complex& c1, const Complex& c2); // 判断相等
    friend bool is_not_equal(const Complex& c1, const Complex& c2); // 判断不相等
    friend double abs(Complex& c); // 取模
    friend void output(const Complex& c); // 输出复数

    static std::string doc;
private:
    double real; // 实部
    double imag; // 虚部
};

complex.cpp

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

// 默认构造函数
Complex::Complex() : real(0), imag(0) {}


// 构造函数
Complex::Complex(double real, double imag) : real(real), imag(imag) {}

//单参构造函数
Complex::Complex(double real) : real(real), imag(0) {}

// 拷贝构造函数
Complex::Complex(const Complex& other) : real(other.real), imag(other.imag) {}

// 返回实部
double Complex::get_real() const {
    return real;
}

// 返回虚部
double Complex::get_imag() const {
    return imag;
}

Complex Complex::add(const Complex& c) {
    return Complex(real + c.real, imag + c.imag);
}

// 复数相加
Complex add(const Complex& c1, const Complex& c2) {
    return Complex(c1.real + c2.real, c1.imag + c2.imag);
}

// 判断相等
bool is_equal(const Complex& c1, const Complex& c2) {
    return (c1.real == c2.real && c1.imag == c2.imag);
}

// 判断不相等
bool is_not_equal(const Complex& c1, const Complex& c2) {
    return !is_equal(c1, c2);
}

// 取模
double abs(Complex& c) {
    return sqrt(c.real * c.real + c.imag * c.imag);
}

// 输出复数
void output(const Complex& c) {
    std::cout << c.real << (c.imag >= 0 ? "+" : "") << c.imag << "i";
}

std::string Complex::doc = "A simplified class";

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();
}

 

 

task3

#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();
}

 接口有默认构造函数，普通构造函数，单参构造函数，复制构造函数，real,imag,abs,复数加法，判断复数是否相等

任务2.

1.c1 += c2代替c1.add(c2)，(c1 == c2)代替is_equal(c1, c2)，(c1 != c3)代替is_not_equal(c1, c3)，对象名能直接输出.

 2：可以用运算符重载来简化类的操作.

task4

f.h

#pragma once
#include <iostream>
#include <numeric>

class Fraction {
private:
    int up;   // 分子
    int down; // 分母

    void simplify(); // 简化分数

public:
    static const std::string doc; // 描述信息

    Fraction(int numerator = 0, int denominator = 1); // 构造函数
    Fraction(const Fraction& f); // 拷贝构造函数

    int get_up() const; // 返回分子
    int get_down() const; // 返回分母
    Fraction negative() const; // 求负

    friend void output(const Fraction& f); //输出
    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);


};

int gcd1(int a, int b);

f.cpp

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

const std::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。";


int gcd1(int a, int b)
{
    return b == 0 ? a : gcd1(b, a % b);
}

Fraction::Fraction(int numerator, int denominator) : up(numerator), down(denominator) {
    if (down == 0) {
        std::cout << "分母不能为0" << std::endl;
    }
    simplify();
}

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

void Fraction::simplify() {
    int gcd = gcd1(up, down);
    up /= gcd;
    down /= gcd;
    if (down < 0) { // 保持负号在分子上
        up = -up;
        down = -down;
    }
}

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

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

Fraction Fraction::negative() const {
    return Fraction(-up, down);
}

void output(const Fraction& f) {
    if (f.down != 0) {

        if (f.down == 1)
            std::cout << f.up << std::endl;
        else
            std::cout << f.up << "/" << f.down << std::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) {
    if (f2.up == 0) {
        std::cout << "分母不能为0" << std::endl;
    }
    else
        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();
}

 

task5

account.h

#pragma once
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 getBalance() const { return balance; }
    double getRate() const { return rate; }
    static double getTotal() { return total; }
    void deposit(int date, double amount);
    void withdraw(int date, double amount);
    void settle(int date);
    void show() const;
};

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 > getBalance())
        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;
}