实验二 类与对象（2）

 

Task4：

Complex.hpp

 

#pragma once

//Complex类的定义
#include<iostream>
#include<string>
#include<math.h>

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

//Complex类的声明
class Complex {
public:
    Complex(double r = 0, double i = 0);
    Complex(const Complex& c);
    ~Complex();
    double get_real() const { return real; }
    double get_imag() const { return imag; }
    void show() 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 double abs(const Complex& c);

private:
    double real, imag;
};


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

//复制构造函数
Complex::Complex(const Complex& c) :real{ c.real }, imag{ c.imag } {}

//析构函数
Complex::~Complex() {}


//非成员函数
void Complex::show()const {
    if (imag > 0)
        cout << real << " + " << imag << "i";
    else if (imag == 0)
        cout << real;
    else
        cout << real << " - " << -imag << "i";
}

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

//友元函数
Complex add(const Complex& c1, const Complex& c2) {
    Complex c3;
    c3.add(c1);
    c3.add(c2);
    return c3;
}

bool is_equal(const Complex& c1, const Complex& c2) {
    if (c1.real == c2.real && c1.imag == c2.imag)
        return true;
    else
        return false;
}

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

 

task4.cpp

 

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

//类测试
void test() {
    using namespace std;

    Complex c1(3, -4);
    const Complex c2(4.5);
    Complex c3(c1);

    cout << "c1 = ";
    c1.show();
    cout << endl;
     
    cout << "c2 = ";
    c2.show();
    cout << endl;
    cout << "c2.imag = " << c2.get_imag() << endl;

    cout << "c3 = ";
    c3.show();
    cout << endl;

    cout << "abs(c1) = ";
    cout << abs(c1) << endl;

    cout << boolalpha;
    cout << "c1 == c3 : " << is_equal(c1, c3) << endl;
    cout << "c1 == c2 : " << is_equal(c1, c2) << endl;

    Complex c4;
    c4 = add(c1, c2);
    cout << "c4 = c1 + c2 = ";
    c4.show();
    cout << endl;

    c1.add(c2);
    cout << "c1 += c2, " << "c1 = ";
    c1.show();
    cout << endl;
}

int main() {
    test();
}

 

结果截图：

（1）原测试结果

 

 （2）更换数据：

 

 

 

Task5

User.hpp

#pragma once

#include<iostream>
#include<iomanip>

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

class User {
public:
    User(string na, string pa = "111111", string em = "");
    ~User();
    void set_email();
    void change_passwd();
    void print_info();
    static void print_n();

private:
    string name, passwd, email;
    static int n;
};

User::User(string na, string pa, string em) {
    name = na;
    passwd = pa;
    email = em;
    n++; }
User::~User() {
    n--;
}
void User::set_email() {
    cout << "Enter email address: ";
    cin >> email;
    cout << "email is set successfully..." << endl;
}
void User::change_passwd() {
    int num = 0;
    cout << "Enter old password: ";
    string input_passwd;
    while (1) {
        cin >> input_passwd;
        if(input_passwd == passwd)
        {
            cout << "Enter new password: ";
            cin >> passwd;
            cout << "new password is set successfully..." << endl;
            break;
        }
        else {
            num++;
            if (num < 3) {
                cout << "password input error. Please re-enter again: ";
                continue;
            }
            else {
                cout << "password input error. Please try after a while. " << endl;
                break;
            }
        }
    }
}
void User::print_info() {
    cout << left
        << setw(8) << "name: " << name << endl
        << setw(8) << "passwd: ";
    for (int i = 0; i < passwd.size(); i++) {
        cout << "*";
    }
    cout << endl
        << setw(8) << "email: " << email << endl;
}
int User::n = 0;
void User::print_n() {
    if (n == 1)
        cout << "there is 1 user." << endl;
    else {
        cout << "there are " << n << " users. " << endl;
    }
}

 

task5.cpp

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

// 测试User类
void test() {
    using std::cout;
    using std::endl;

    cout << "testing 1......\n";
    User user1("Jonny", "92197", "xyz@hotmail.com");
    user1.print_info();

    cout << endl
        << "testing 2......\n\n";

    User user2("Leonard");
    user2.change_passwd();
    user2.set_email();
    user2.print_info();

    cout << endl;
    User::print_n();
}

int main() {
    test();
}

 

结果截图：

测试一：

 

 测试二：

 

 测试三：