• 實驗任務三

sourcecode inComplex.hpp ：

 1 #include <iostream>
 2 
 3 using namespace std;
 4 class Complex{
 5     public:
 6     Complex(){
 7         real = 0;
 8         imag = 0;
 9     }
10     Complex(double c1): real(c1), imag(0) {};
11     Complex(double c1,double c2): real(c1) , imag(c2) {};
 
12     Complex(Complex& c3): real(c3.real), imag(c3.imag) {};
13     double get_real() const;
14     double get_imag() const ;
15     void show() const ;
16     void add(const Complex& c1);
17     
18     friend Complex add(const Complex& c1,const Complex& c2);
19     friend bool is_equal(const
 
 Complex& c1, const Complex& c2) ;
20     friend double abs(Complex& c1);
21     
22     private:
23     double real;
24     double imag;
25 };
26 
27 double Complex::get_real () const{
28     return real;
29 }
30 
31 double Complex::get_imag () const{
32     return imag;
33 }
34 
35 void Complex::show() const
 
{
36     if(imag>0)
37         cout << real << "+ " << imag << "i";
38     else if(imag==0)
39         cout<<real;
40     else cout<<real<<" - "<<(-imag)<<"i"; 
41 }
42 
43 void Complex::add(const Complex& c1){
44     real += c1.real;
45     imag += c1.imag;
46 }
47 
48 Complex add(const Complex& c1,const Complex& c2){
49     Complex temp(0,0);
50     temp.real = c1.real + c2.real;
51     temp.imag = c1.imag + c2.imag;
52     return temp;
53 }
54 
55 bool is_equal(const Complex& c1, const Complex& c2){
56     return (c1.real == c2.real && c1.imag == c2.imag);
57 }
58 
59 double abs(Complex& c1){
60     return c1.real*c1.real + c1.imag*c1.imag;
61 }

TheRunningresults ：

• 實驗任務四

sourcecode inUser.hpp ：

 1 #include <iostream>
 2 #include <iomanip>
 3 #include <string>
 4 #include <cstring>
 5 using namespace std;
 6 class User
 7 {
 8     public:
 9         User(string n);
10         User(string n,string p,string e);
11         ~User(){};
12         void set_email();
13         void change_passwd ();
14         void print_info();
15         static void print_n();
16     private:
17         string name;
18         string passwd;
19         string email;
20         static int num;
21 };
22 int User::num=0;
23 User::User(string n):name(n),passwd("111111"),email(" "){
24     ++num;
25 }
26 User::User(string n,string p,string e):name(n),passwd(p),email(e){
27     ++num;
28 }
29 void User::set_email(){
30     string input;
31     cout<<"Enter email address:";
32     cin>>input;
33     string key_="@";
34     if(input.find(key_)!=string::npos){
35         email=input;
36         cout<<"email is set successfully..."<<endl;
37     }else
38         cout<<"Wrong format!";
39 
40 }
41 void User::change_passwd(){
42     int times=3;
43     int change_pw=0;
44     cout<<"Enter old password:";
45     for(int i=0;i<times;++i){
46         string oldpsw;
47         cin>>oldpsw;
48         if(strcmp(oldpsw.c_str(),passwd.c_str())!=0){
49             cout<<"password input error. Please re-enter again: ";
50             continue;
51         }
52         cout<<"Enter new password:";
53         string newpsw;
54         cin>>newpsw;
55         if (newpsw.size()>=6){
56             change_pw=1;
57             passwd=newpsw;
58             cout<<"new passwd is set successfully..."<<endl;
59         }else{
60             cout << "passwd format error！\n";
61         }
62     }
63     if(change_pw==0){
64         cout<<"Please try after a while.\n";
65     }
66 }
67 void User::print_info(){
68     cout<<"name:\t"<<name<<endl;
69     cout<<"passwd:\t"<<"******"<<endl;
70     cout<<"email:\t"<<email<<endl;
71 }
72 void User::print_n(){
73 
74     if(num==1){
75         cout<<"there is 1 user."<<endl;
76     }
77     else{
78         cout<<"there are "<<num<<" users."<<endl;
79     }
80 }

TheRunningresults ：

• 實驗總結

通過這次實驗，掌握了類和物件的基礎知識，也熟悉了String的使用。