实验一 类与对象

实验结论

实验任务3

#ifndef COMPLEX_HPP
#define COMPLEX_HPP

#include <iostream>
#include <cmath>
using namespace std;
class Complex{
    public:
        Complex(double a=0,double b=0){
            real=a;
            imag=b;
        }
        ~Complex(){}
        Complex(const Complex  &c){
            real=c.real;
            imag=c.imag;
        }
        double get_real()const;
        double get_imag()const;
        void show()const;
        void add(const Complex &c);
    
        friend Complex add(const Complex &c1,const Complex &c2);
        friend bool is_equal(const Complex &c1,const Complex &c2);
        friend double abs(Complex &c);
        
    private:
        double real,imag;
};

double Complex::get_real() const{
    return real;
}
double Complex::get_imag() const{
    return imag;
}
void Complex::show() const{
    using namespace std;
    if (imag>0)
        cout <<real<<"+"<<imag<<"i";
    else if (imag<0)
        cout <<real<<imag<<"i";
    else 
        cout <<real;
}
void Complex::add(const Complex &c){
    real+=c.get_real();
    imag+=c.get_imag(); 
} 

Complex add(const Complex &c1,const Complex &c2){
    Complex c;
    c.real=c1.real+c2.real;
    c.imag=c1.imag+c2.imag;
    return c;
} 
bool is_equal(const Complex &c1,const Complex &c2){
    if(c1.real==c2.real && c1.imag==c2.imag){
        return true;
    }else 
    return false;
}
double abs(Complex &c){
    return sqrt(c.real*c.real+c.imag*c.imag);
}

#endif

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

int main()
{
    using namespace std;

    Complex c1(6, -5);
    const Complex c2(3.6);
    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;
}

实验任务4

#ifndef USER_HPP
#define USER_HPP
#include<iostream>
#include <string>

using namespace std;

class User{
    public:
        User(string name0,string passwd0="111111",string email0=""):name(name0),passwd(passwd0),email(email0){
            ++n;
        }
        void set_email();
        void change_passwd();
        void print_info();
        static void    print_n();
    private:
        string name;
        string passwd;
        string email;
        static int n;

    
};
int User::n=0;
void User::set_email(){
    cout<<"Enter email address: ";
    cin>>email;
    cout<<"email is set successfully..."<<endl;
}

void User::change_passwd(){
    cout<<"Enter old password: ";
    string passwd1;
    string passwd2;
    int i=1;
    for(i=1;i<=3;i++){
        cin>>passwd1;
        if(passwd1!=passwd){
            if(i<=2){
                
                cout<<"password input error. Please re-enter again: ";
                
            }
            if(i==3){
                
                cout<<"password input error. Pleasa try after a while."<<endl;
                
            }
        }
        else{
            cout<<"Enter new passwd: ";
            cin>>passwd2;
            passwd=passwd2;
            cout<<"new passwd is set successfully..."<<endl;
            break;
        }
    }
}
void User::print_info(){
    cout<<"name:   "<<name<<endl;
    cout<<"passwd: ******"<<endl;
    cout<<"email: "<<email<<endl;
}
void User::print_n(){
    cout<<"there are "<<n<<" users.";
}

#endif

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

int main()
{
    using namespace std;

    cout << "testing 1......" << endl;
    User user1("Curry", "942030", "stc@nbastar.com");
    user1.print_info();

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

    User::print_n();
}