实验二 c++

task1

代码：

task1.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();

task.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;
}

main.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();
}

运行截图：

问题一：

不行

 

问题二：

T(int x = 0, int y = 0);

构造一个普通的类t；对象创建时被调用

T(const T &t); 

将t的内容复制到其他类中；对象创建时被调用
T(T &&t); 

将t的内容转移到其他类中；对象创建时被调用
~T();

用来清理善后；在对象生命周期结束时调用

问题三：不能

task2

代码：

#pragma once
#include<iostream>
#include<string>

using namespace std;
 
class Complex{
public:
    Complex(double r=0,double i=0);
    Complex(const Complex &c);
    ~Complex();
    void add(const Complex &c);
    
    double get_real() const;
    double get_imag() const;
    
    static const std::string doc; 
    
    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 double abs(const Complex &c);
    friend void output(const Complex &c);
     
private:
    double real,imag;
};

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

using namespace std;
using std::string; 

const std::string Complex::doc{"a simplified complex class"};

Complex::Complex(double r,double i):real{r},imag{i}{}
Complex::Complex(const Complex &c):real{c.real},imag{c.imag}{}
Complex::~Complex(){}

void Complex::add(const Complex &c){
    real+=c.real;
    imag+=c.imag;
}
double get_imag()const{
    return imag;
}
double get_real()const{
    return real;
}
void output(const Complex &c){
    if(c.imag>=0)
        cout<<c.real<<"+"<<c.imag<<"i"<<endl;
    else
        cout<<c.real<<c.imag<<"i"<<endl;
}
double abs(const Complex &c){
    return sqrt(pow(c.real,2)+pow(c.imag,2));
}
Complex add(const Complex &c1,const Complex &c2){
    Complex c;
    c.real=c1.real+c2.real;
    c.imag=c1.imag+c2.imag;
    return c;
}
bool is_equal(const Complex &c1,const Complex &c2){
    if(c1.real==c2.real&&c1.imag==c2.imag)
        return true;
    else
        return false;
}
bool is_not_equal(const Complex &c1,const Complex &c2){
    if(c1.real==c2.real&&c1.imag==c2.imag)
        return false;
    else
        return true;
}

#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();
}

运行截图：

task3

代码：

#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();
}

运行截图：

选用合适的标准库可以大大便捷我们编写程序的工作

task4

代码：

#pragma once
#include<string>
#include<iostream>

using namespace std;

class Fraction{
public:
    Fraction(int x=0,int y=1);
    Fraction(const Fraction &f);
    ~Fraction();
    static const string doc;
    int get_up();
    int get_down();
    Fraction negative();
    
    friend void output(Fraction &f);
    friend Fraction add(Fraction &f1,Fraction &f2);
    friend Fraction sub(Fraction &f1,Fraction &f2);
    friend Fraction mul(Fraction &f1,Fraction &f2);
    friend Fraction div(Fraction &f1,Fraction &f2);
private:
    int up;
    int down;
};

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

using namespace std;
using std::string; 
using std::endl;
using std::string;

const std::string Fraction::doc = "Fraction类基础功能测试";

Fraction::Fraction(int x,int y):up{x},down{y}{
int a = abs(x),b = y;
    while (b != 0) {
        int temp = b;
        b = a % b;
        a = temp;
    }
    up = x / a;
    down = y / a;
}

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

int gcd(int x,int y){
    int r=x%y;
    while(r!=0){
        x=y;
        y=r;
        r=x%y;
    }
    return y;
}

int lcm(int x,int y){
    return x*y/gcd(x,y);
}
int Fraction::get_up(){
    return up;
}
int Fraction::get_down(){
    return down;
}
Fraction Fraction::negative() {
     Fraction f;
     if ( down > 0) {
        f.up = -up;
        f.down = down;
    }
  
     else if ( down < 0){
        f.up = up;
        f.down = -down;
     }
    return f;
}
void output(Fraction &f){
    if(f.up==0){
        cout<<"0";
        return;
        }
    else if(f.down==0){
        cout<<"分母不能为零！";
        return;
    }
    cout<<f.up<<"/"<<f.down;
}

Fraction add(Fraction &f1,Fraction &f2){
    Fraction f;
    int m=lcm(f1.get_down(),f2.get_down());
    f.down=m;
    f.up=m/f1.get_down()*f1.get_up()+m/f2.get_down()*f2.get_up();
    return f;
}
Fraction sub(Fraction &f1,Fraction &f2){
    Fraction f;
    int m=lcm(f1.get_down(),f2.get_down());
    f.down=m;
    f.up=m/f1.get_down()*f1.get_up()-m/f2.get_down()*f2.get_up();
    return f;
}
Fraction mul(Fraction &f1,Fraction &f2){
    Fraction f;
    f.down=f1.get_down()*f2.get_down(); 
    f.up=f1.get_up()*f2.get_up();
    return f;
}
Fraction div(Fraction &f1,Fraction &f2){
    Fraction f;
    f.down=f1.get_down()*f2.get_up();
    f.up=f1.get_up()*f2.get_down();
    return f;
}

#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),f;
    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;

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

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

运行截图：

task5：

代码：

#ifndef __ACCOUNT_H__
#define __ACCOUNT_H__
 
class SavingAccount {
private:
    int id;
    double balance;
    double rate;
    int lastDate;
    double accumulation;
 
    static double total;

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

#include "account.h"
#include <cmath>
#include <iostream>
using namespace std;

double SavingAccount::total = 0;

SavingAccount::SavingAccount(int date, int id, double rate)
    : id{ id }, balance{ 0 }, rate{ rate }, lastDate{ date }, accumulation{ 0 } {
   cout << date << "\t#" << id << "is created" << endl;
}
 
void SavingAccount::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 SavingAccount::deposit(int date, double amount) {
    record(date, amount);
    }

void SavingAccount::withdraw(int date, double amount) {
   if (amount > getBalance())
       cout << "Error: not enough money" << endl;
    else
         record(date, -amount);
}
 
void SavingAccount::settle(int date) {
    double interest = accumulate(date) * rate / 365;
    if (interest != 0)
        record(date, interest);
    accumulation = 0;
}
 
void SavingAccount::show() const {
     cout << "#" << id << "\tBalance: " << balance;
 }

#include "account.h"
#include <iostream>
using namespace std;

int main() {
    SavingAccount sa0(1, 21325302, 0.015);
    SavingAccount sa1(1, 58320212, 0.015);
    sa0.deposit(5, 5000);
    sa1.deposit(25, 10000);
    sa0.deposit(45, 5500);
    sa1.deposit(60, 4000);
 
    sa0.settle(90);
    sa1.settle(90);
 
    sa0.show(); cout << endl;
    sa1.show(); cout << endl;
    cout << "Total: " << SavingAccount::getTotal() << endl;
    return 0; 
}

运行截图：