实验2 类和对象

task 4.

Complex.hpp
#include<iostream>
#include<cmath>
using namespace std;
 
class Complex
{
public:
    Complex(double a = 0,double b = 0):real{a},imag{b} {};
    Complex(const Complex &c1);
    ~Complex() = default;
 
    double get_real() const {return real;}
    double get_imag() const {return imag;}
    void show() const;
    void add(Complex const &c1);
    
 
    friend Complex add(Complex const&c1,Complex const&c2);
    friend bool is_equal(Complex const&c1,Complex const&c2);
    friend double abs(Complex const&c1); 
private:
    double real;
    double imag;
};
 
Complex::Complex(const Complex &c1)
{
    real = c1.real;
    imag = c1.imag;
}
 
void Complex::show() const
{
    if(imag == 0)
        cout << real ;
    else if(imag < 0)
        cout << real <<" - "<< abs(imag) << "i" ;
    else
        cout << real <<" + "<< imag << "i" ;
}
 
void Complex::add(Complex const&c1)
{
    real += c1.real;
    imag += c1.imag;
}
 
 
Complex add(Complex const&c1,Complex const&c2)
{
    Complex c3;
    c3.real = c1.real + c2.real;
    c3.imag = c1.imag + c2.imag;
    return c3;
}
 
bool is_equal(Complex const&c1,Complex const&c2)
{
    if(c1.real == c2.real&&c1.imag ==c2.imag)
        return true;
    return false;
}
 
double abs(Complex const&c1)
{
    return sqrt(c1.real*c1.real + c1.imag*c1.imag);
}

Complex.cpp
#include "Complex.hpp"
#include <iostream>
 
int main()
{
    using namespace std;
 
    Complex c1(15, -4);
    const Complex c2(5.5);
    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;
 
    return 0;
}

 

task 5.

User.hpp
#include<iostream>
#include<string>
using namespace std;
 
class User
{
public:
    User(string name,string passwd = "111111",string email = ""):n{name}, p{passwd}, e{email}{count++;}
    ~User() = default;    
 
    void set_email();
    void change_passwd();
    void print_info();
    static void print_n();
 
private:
    string n,p,e;
    static int count;
};
 
 int User::count = 0;
 
void User::set_email()
{
    cout << "Enter email adress: " ;
    cin >> e ;
    cout << "email is set successfully..." << endl;
}
 
void User::change_passwd()
{
    cout << "Enter old password: ";
    string temp;
    int i = 3;
    while(i)
    {
        cin >> temp;
        if(temp == p)
        {
            cout << "new passwd is set successfully..." << endl;
            break;
        }
        else 
        {
            i--;
            if(i != 0)
                cout << "password input error. Please re-enter again: " ;
        }
        if(i == 0)
        {
            cout << "password input error. Please try after a while." << endl;
        }
    }
 
}
 
void User::print_info()
{
    cout << "name:   " << n << endl;
    cout << "passwd: " << "******" << endl;
    cout << "email:  " << e << endl;
}
 
void User::print_n()
{
    cout << "there are " << count << " users." << endl;
}

task5.cpp
#include "User.hpp"
#include <iostream>
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();
}