实验一类与对象

complex.hpp源代码

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

class Complex
{
public:
    Complex(int r = 0, int i = 0) : real((double)r), imag((double)i) {}
    // Complex();
    Complex(double r);           //带一个参数
    Complex(double r, double i); //带两个参数
    ~Complex() = default;
    Complex(const Complex &a) //复制构造函数
    {
        real = a.real;
        imag = a.imag;
    }
    double get_real() const //返回函数实部
    {
        return real;
    }
    double get_imag() const //返回函数虚部
    {
        return imag;
    }
    void show() const //输出复数
    {
        if (get_imag() > 0)
            cout << get_real() << " + " << get_imag() << "i" << endl;
        else if (get_imag() == 0)
            cout << get_real() << endl;
        else
            cout << get_real() << " - " << -get_imag() << "i" << endl;
    }
    void add(const Complex &a) //用于把一个复数加到自身
    {
        real += a.real;
        imag += a.imag;
    }
    friend Complex add(const Complex &a1, const Complex &a2);   //友元函数：实现两个复数相加
    friend bool is_equal(const Complex &a1, const Complex &a2); //友元函数，判断相等
    friend double abs(const Complex &a);                        //友元函数，对复数进行取模运算

private:
    double real;
    double imag;
};
Complex::Complex(double r)
{
    real = r;
    imag = 0;
}

Complex::Complex(double r, double i)
{
    real = r;
    imag = i;
}

Complex add(const Complex &a1, const Complex &a2)
{
    Complex a3;
    a3.real = a1.real + a2.real;
    a3.imag = a1.imag + a2.imag;
    return a3;
}
bool is_equal(const Complex &a1, const Complex &a2)
{
    if ((a1.real == a2.real) && (a1.imag == a2.imag))
        return true;
    else
        return false;
}
double abs(const Complex &a)
{
    double sum;
    sum = sqrt(a.real * a.real + a.imag * a.imag);
    return sum;
}

task3.cpp源码

#include "complex.hpp"
#include <iostream>
// using namespace std;
int main()
{
    using namespace std;

    Complex c1(4, -5);
    const Complex c2(3.5);
    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;
}

运行截图：

 user.hpp源码

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

class user
{
private:
    string name;
    string password;
    string email;
    static int n;

public:
    user(string name1);                                  //带一个参数
    user(string nameq, string password1, string email1); //带三个参数
    ~user() = default;
    void set_email()
    {
        string h;
        cout << "Enter email address: ";
        cin >> h;
        email = h;
        // cout << endl;
        cout << "email is set successfully" << endl;
    }
    void change_passwd()
    {
        string p, newp; // p为旧密码，newp为新密码
        cout << "Enter old password: ";
        // cin >> p;
        int t = 0;
        for (int i = 1; i <= 3; i++)
        {
            cin >> p;
            // int t = 0;
            if (p != password)
            {
                t++;
                if (t == 3)
                {
                    cout << "password input error.Please try after a while." << endl;
                    ;
                    break;
                }
                else
                    cout << "password input error. Please re-enter again: ";
            }
            else
            {
                cout << "Enter new password: ";
                cin >> p;
                cout << "new password is set successfully..." << endl;
                break;
            }
        }
    }
    void print_info()
    {
        cout << "name: " << name << endl;
        cout << "password: ******" << endl;
        cout << "email: " << email << endl;
    }
    static void print_n()
    {
        cout << "there are " << n << " users." << endl;
    }
};
int user::n = 0;

user::user(string name1)
{
    name = name1;
    password = "111111";
    email = " ";
    n++;
}
user::user(string name1, string password1, string email1)
{
    name = name1;
    password = password1;
    email = email1;
    n++;
}

task4.cpp源码

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

int main()
{
    using namespace std;

    cout << "testing 1......" << endl;
    user user1("Lisa", "11342", "lisa@hotmail.com");
    user1.print_info();

    cout << endl
         << "testing 2......" << endl
         << endl;
    user user2("Sumille");
    user2.change_passwd();
    user2.set_email();
    user2.print_info();

    user::print_n();
}

运行截图