实验1 类与对象

实验任务3

//Complex.hpp

#ifndef COMPLEX_HPP
#define COMPLEX_HPP

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

class Complex
{
public:
    Complex() : real{0}, imag{0} {};
    Complex(double real0) : real{real0} {};
    Complex(double real0, double imag0) : real{real0}, imag{imag0} {};
    Complex(const Complex &c) : real{c.real}, imag{c.imag} {};
    ~Complex() = default;

    //成员函数
    double get_real() const;
    double get_imag() const;
    void show() const;
    void add(const Complex &cc);

    //友元函数
    friend Complex add(const Complex &cc1, const Complex &cc2);
    friend bool is_equal(const Complex &cc1, const Complex &cc2);
    friend double abs(const Complex &cc1);

private:
    double real;
    double imag;
};

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

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

void Complex::show() const
{
    if (imag < 0)
        cout << real << " - " << 0 - imag << "i";
    else if (imag == 0)
        cout << real;
    else
        cout << real << " + " << imag << "i";
}

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

Complex add(const Complex &cc1, const Complex &cc2)
{
    Complex c;
    c.real = cc1.real + cc2.real;
    c.imag = cc1.imag + cc2.imag;
    return c;
}

bool is_equal(const Complex &cc1, const Complex &cc2)
{
    if (cc1.real == cc2.real && cc1.imag == cc2.imag)
    {
        return true;
    }
    else
        return false;
}

double abs(const Complex &cc1)
{
    return sqrt(cc1.real * cc1.real + cc1.imag * cc1.imag);
}
#endif

//task3.cpp

#include "Complex.hpp"
#include <iostream>
int main()
{
    using namespace std;
    Complex c1(4, -10);
    const Complex c2(7.3);
    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;
}

测试结果：

 

实验任务4

//User.hpp

#ifndef USER_HPP
#define USER_HPP

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

class User
{
public:
    User(string name0, string password0 = "111111", string email0 = "");
    void set_email();
    void change_passwd();
    void print_info() const;
    static void print_n();

private:
    string name;
    string password;
    string email;
    static int count;
};

int User::count = 0;

User::User(string name0, string password0, string email0)
{
    name = name0;
    password = password0;
    email = email0;
    count++;
}

void User::set_email()
{
    string nemail;
    cout << "Enter email address: ";
    cin >> nemail;
    email = nemail;
    cout << "email is set successfully..." << endl;
}

void User::change_passwd()
{
    string opw, npw;
    int times = 1;
    cout << "Enter old password: ";
    cin >> opw;
    while (opw != password)
    {
        if (times == 3)
        {
            cout << "password input error. please try after a while." << endl;
            return;
        }
        cout << "password input error. Please re-enrer again: ";
        cin >> opw;
        times++;
    }
    cout << "Enter new password: ";
    cin >> npw;
    password = npw;
    cout << "new password is set successfully..." << endl;
}

void User::print_info() const
{
    cout << left << setw(8) << "name:" << name << endl;
    cout << left << setw(8) << "passwd: " << "******" << endl;
    cout << left << setw(8) << "email:" << email << endl;
}

void User::print_n()
{
    cout << "there are " << count << " users." << endl;
}
#endif

//task4.cpp

#include "User.hpp"
#include <iostream>
int main()
{
    using namespace std;
    cout << "testing 1......" << endl;
    User user1("Mark", "110119", "cxk@hotmail.com");
    user1.print_info();
    cout << endl
         << "testing 2......" << endl
         << endl;
    User user2("Terry");
    user2.change_passwd();
    user2.set_email();
    user2.print_info();
    User::print_n();
}

测试结果：

密码输入错误：

密码输入正确：

 

实验总结：

1、对于const型数据声明、定义的形式，使用场景还不太熟悉