实验一 类与对象

实验任务3

"Complex.hpp"

#ifndef COMPLEX_HPP
#define COMPLEX_HPP

#include <bits/stdc++.h>
using namespace std;

class Complex
{
    public:
        Complex(double a=0.0, double b=0.0):real(a),image(b){}
        Complex(const Complex& c): real(c.real),image(c.image){}
        double get_real() const{ return real;}   //返回real
        double get_imag() const{ return image;}  //返回虚部
        void show();                             //输出复数
        void show() const;
        void add(Complex c2){ real += c2.get_real(); image += c2.get_imag();}  //用于把一个复数加到自己身上
        friend Complex add(Complex const &c1, Complex const &c2);               //实现两个复数相加
        friend string is_equal(Complex const &c1, Complex const &c2);          //判断两个复数是否相等
        friend double abs(Complex c1);                                         //取模运算
    private:
        double real, image;
};
void Complex::show()  //输出复数                                
{
    cout << real <<" ";
    if(image > 0.0) cout << "+ " <<fabs(image) <<"i";
    else if(image < 0.0)           cout << "- " <<fabs(image) <<"i";
}

void Complex::show() const //输出复数
{
    cout << real <<" ";
    if(image > 0.0) cout << "+ " <<fabs(image) <<"i";
    else if(image < 0.0)           cout << "- " <<fabs(image) <<"i";
}


Complex add(Complex const &c1, Complex const &c2) //实现两个复数相加
{
    Complex res(c1.real+c2.real, c1.image+c2.image);
    return res;
}

string  is_equal(Complex const &c1, Complex const &c2) //判断两个复数是否相等
{
    string res;
    if(c1.real==c2.real&&c1.image==c2.image) res = "true";
    else                                     res = "false";
    return res;
}

double abs(Complex c1)  //取模运算
{
    double res;
    res = sqrt(pow(c1.get_real(),2) + pow(c1.get_imag(),2));
    return res;
}

"task3.cpp"

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

int main()
{
    using namespace std;

    Complex c1(5, -12);
    const Complex c2(5.4);
    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：

 

 

实验任务4

"User.cpp"

#ifndef USER_HPP
#define USER_HPP

#include <bits/stdc++.h>
using namespace std;

class User
{
    public:
        User(){n++;}
        User(string na, string pass = "111111", string em = ""):name(na), passwd(pass), email(em){ n++; }
        void set_email();   //设置邮箱
        void change_passwd();  //修改密码
        void print_info();   //打印数据
        static void print_n();  //打印用户数
    private:
        string name;    //姓名
        string passwd;  //密码
        string email;   //邮箱
        static int n;  //用户数
};

int User::n = 0; 


void User::set_email()   //设置邮箱
{
    cout << "Enter email addres: ";
    string temp;
    cin >> temp;
    email = temp; 
    cout << "Eamil is set successfully..." <<endl;
}

void User::change_passwd() //修改密码
{
    cout << "Enter old password: ";
    int count = 0;
    string temp;
    do
    {
        cin >> temp;
        if( temp == passwd)
        {    
            string temp2;
            cout << "Enter new password: ";
            cin >> temp2;
            passwd = temp2;
            cout << "New password is set successfully..." << endl;
            return;
        }
    else
        {
            cout << "Passsword input error. Please re-enter again: ";
        }
        count ++;
    }while(temp != passwd && count <= 2);
    cout << "Password input erroe. Please try after a while."<<endl;
    return ;
}

void User::print_info()  //打印数据
{
    cout << "name:    " << name << endl;
    cout << "passord: " <<"******" <<endl;
    cout << "email:   " << email << endl;
}
void User::print_n()   //打印用户数
{
    if(n==0) cout << "there is no users.";
    else if (n==1) cout << "there is 1 user.";
    else cout << "there are " << n << " users.";
    cout << endl;
}
#endif

 

"task4.cpp"

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

int main()
{
    using namespace std;

    cout << "testing 1......" << endl;
    User user1("Handsome_LSY", "163", "Shuaige@gmail.com");
    user1.print_info();

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

    User::print_n();
}

 

运行结果1:

 运行结果2: