实验二 类与对象2

4. 实验任务4
不使用C++标准库，自行设计并实现一个简化版复数类Complex

Complex.hpp

#include <iostream>
#include <math.h> 
using namespace std; 

class Complex {
    
public:
    Complex(double r = 0, double i = 0): real{r}, imag{i} {}
    Complex(const Complex& obj): real{obj.real}, imag{obj.imag} {}
    
    double get_real() const {
        return real;
    }
    double get_imag() const {
        return imag;
    }
    void show() const;
    void add(const Complex& c);
    
    friend Complex add(Complex c1, Complex c2);
    friend bool is_equal(Complex c1, Complex c2);
    friend int abs(Complex c1);
    
private:
    double real, imag;
};

void Complex::show() const {
    if(imag == 0) {
        cout << real;
    }
    else if(imag < 0) {
        cout << real << " - " << -1 * imag << "i";
    } else{
        cout << real << " + " << imag << "i";
    }
}
void Complex::add(const Complex& c) {
    real += c.real;
    imag += c.imag;
}

Complex add(Complex c1, Complex c2) {
    Complex c3(c1.real + c2.real, c1.imag + c2.imag);
    return c3;
}
bool is_equal(Complex c1, Complex c2) {
    return (c1.real == c2.real && c2.imag == c1.imag);
}
int abs(Complex c) {
    return sqrt(c.real * c.real + c.imag * c.imag);
}

task4.cpp

#include "Complex.hpp"
#include <iostream>
#include <math.h> 
// 类测试 
void test() {
    using namespace std;

    Complex c1(3, -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;
}

int main() {
    test();
}

 

 

 

5. 实验任务5

User.hpp

#include <iostream>
#include <string>

using namespace std;

class User {

public:
    User(string n, string p = "111111", string e = "") : 
        name{ n }, passwd{ p }, email{ e } { 
            num ++; 
        }

    void set_email();
    void change_passwd();
    void print_info();
    static void print_n() {
        cout << "there are " << num << " users."; 
    }

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

int User::num = 0;

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

void User::change_passwd() {
    string old_pwd, new_pwd;
    int count = 1;

    cout << "Enter old password: ";
    cin >> old_pwd;
    
    while(old_pwd != passwd) {
        cout << "password input error. Please re-enter again: ";
        cin >> old_pwd;
        count++;
        
        if(count == 3) {
            cout << "password input error. Please try after a while. " << endl;
            return;
        }
    }
    cout << "Enter new password: ";
    cin >> new_pwd; 
    passwd = new_pwd;
    
    cout << "new passwd is set successfully..." << endl;
    
}

void User::print_info() {
    string pwd(passwd.length(), '*');
    cout << "name:\t" << name << endl;
    cout << "passwd:\t" << pwd << endl;
    cout << "email:\t" << email << endl;    
}

task5.cpp

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

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

 

 

 

 

 

 

实验总结 ：

hpp文件中 ，不能忘了导入需要的头文件， using 所需要的命名空间中的成员