实验一：类与对象

实验3：

Complex.hpp:

#ifndef Complex_hp
#define Complex_hp


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

class Complex {
public:
    Complex() = default;
    Complex(double a, double b = 0) :real(a), image(b) {}
    Complex(const Complex& tag) :real(tag.real), image(tag.image) {}
    ~Complex() {}
    double get_real()const;
    double get_imag()const;
    void show()const;
    void add(const Complex& k);
    friend Complex add(const Complex& k1, const Complex& k2);
    friend bool is_equal(const Complex& k1, const Complex& k2);
    friend double abs(const Complex& k);
private:
    double real;
    double image;
};
double Complex::get_real()const {
    return real;
}
double Complex::get_imag()const {
    return image;
}
void Complex::show()const {
    if (image > 0)
    {
        cout << real << '+' << image << 'i' << endl;
    }
    else if (image < 0)
    {
        cout << real << image << 'i' << endl;
    }
    else
    {
        cout << real << endl;
    }
}
void Complex::add(const Complex& k) {
    real = real + k.real;
    image = image + k.image;
}
Complex add(const Complex& k1, const Complex& k2) {
    Complex k3;
    k3.real = k1.real + k2.real;
    k3.image = k1.image + k2.image;
    return k3;
}
bool is_equal(const Complex& k1, const Complex& k2) {
    if (k1.real == k2.real && k1.image == k2.image)
        return true;
    else
        return false;
}
double abs(const Complex& k) {
    return sqrt(k.real * k.real + k.image * k.image);
}












#endif // 

task3.cpp:

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

int main()
{
    using namespace std;

    Complex c1(6, -8);
    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;
}

运行结果：

 

 实验4：

User.hpp:

#ifndef User_hpp
#define User_hpp
#include <iostream>
#include <string>
using namespace std;


class User {
    User(string s1, string s2 = "111111", string s3 = "      ") : name(s1), password(s2), email(s3) { n++; }
    ~User() {}
    void set_email() {
        string s4;
        cout << "Enter email address:";
        cin >> s4;
        cout << endl;
        cout << "email is set successfully" << endl;
    }
    void change_passwd() {
        string s4,s5;
        int m=1;
        cout << "Enter old password:";
        cin >> s4;
        while (s4 != password && m < 3)
        {
            cout << "password input error.Please re-enter again:";
            cin >>s4;
            m++;
        }
        if (m == 3)
        {
            cout << "password input error.Please try after a while." << endl;
        }
        if (s4 == password && m < 3)
        {
            cout << "enter newpassword:";
            cin >> s5;
        }
    }
    void print_info() {
        cout << "name:"<<name<<endl;
        cout << "password:******"<<endl;
        cout << "email:" << email << endl;
    }
    static void print_n() {
        if(n==1)
        {
        cout << "there is" << n << "user" << endl;
        }
        else if (n==0)
        {
        cout<<"there is no user"<<endl;
        }
        else
        {
        cout << "there are" << n << "users" << endl;
        }
    }
private:
    static int n;
    string name;
    string password;
    string email;
};
int User::n=0;
#endif

task4.cpp:

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

int main()
{
    using namespace std;

    cout << "testing 1......" << endl;
    User user1("Bill Gates", "114514", "appleissobad@outlook.com");
    user1.print_info();

    cout << endl
         << "testing 2......" << endl
         << endl;
    User user2("Tim Cook");
    user2.change_passwd();
    user2.set_email();
    cout << endl;
    user2.print_info();

    User::print_n();
}

运行结果：