实验1 类与对象
作者：互联网
T1:
Complex.hpp
1 #include<iostream>
2 #include<cmath>
3 using namespace std;
4 class Complex {
5 public:
6 Complex() = default;
7 Complex(double r, double i) :real(r), imag(i) {}
8 Complex(double r) :real(r),imag(0) {}
9 Complex(const Complex& c) :real(c.real), imag(c.imag) {}
10 double get_real() const { return real; }
11 double get_imag() const { return imag; }
12 void show() const;
13 void add(const Complex c);
14 friend Complex add(const Complex c1, const Complex c2);
15 friend bool is_equal(const Complex c1, const Complex c2);
16 friend double abs(const Complex c);
17 private:
18 double real=0, imag=0;
19
20 };
21 void Complex::show() const{
22 if (imag > 0)
23 cout << real << '+' << imag << 'i' << endl;
24 else if (imag == 0)
25 cout << real << endl;
26 else
27 cout << real << imag <<'i'<< endl;
28 }
29 void Complex::add(const Complex c) {
30 real += c.real;
31 imag += c.imag;
32 }
33 Complex add(Complex c1, const Complex c2) {
34 c1.add(c2);
35 return c1;
36
37 }
38 bool is_equal(const Complex c1, const Complex c2) {
39 if (c1.real == c2.real && c1.imag == c2.imag)
40 return true;
41 else
42 return false;
43 }
44 double abs(const Complex c) {
45 double sqr;
46 sqr = sqrt(c.real * c.real + c.imag * c.imag);
47 return sqr;
48 }
Complextest.cpp
1 #include "Complex.hpp"
2 #include <iostream>
3
4 int main()
5 {
6 using namespace std;
7
8 Complex c1(6,-8);
9 const Complex c2(6.3);
10 Complex c3(c1);
11
12 cout << "c1 = ";
13 c1.show();
14 cout << endl;
15
16 cout << "c2 = ";
17 c2.show();
18 cout << endl;
19 cout << "c2.imag = " << c2.get_imag() << endl;
20
21 cout << "c3 = ";
22 c3.show();
23 cout << endl;
24
25 cout << "abs(c1) = ";
26 cout << abs(c1) << endl;
27
28 cout << boolalpha;
29 cout << "c1 == c3 : " << is_equal(c1, c3) << endl;
30 cout << "c1 == c2 : " << is_equal(c1, c2) << endl;
31
32 Complex c4;
33 c4 = add(c1, c2);
34 cout << "c4 = c1 + c2 = ";
35 c4.show();
36 cout << endl;
37
38 c1.add(c2);
39 cout << "c1 += c2, " << "c1 = ";
40 c1.show();
41 cout << endl;
42 }
T2:
User.hpp
1 #include<iostream>
2 #include<string>
3
4 using namespace std;
5
6 class User {
7 public:
8 User(string namel,string passwdl="111111",string emaill=""):name(namel),passwd(passwdl),email(emaill){}
9 void set_email();
10 void change_passwd();
11 void print_info();
12 static void print_n();
13 private:
14 string name, passwd, email;
15 static int n;
16 };
17 void User::set_email() {
18 cout << "Enter email address:";
19 cin >> email;
20 cout << endl << "Email has been set successfully!";
21 }
22 void User::change_passwd() {
23 string oldpw;
24 int i=0;
25 cout << "Please enter the old password:";
26
27 while (i < 3) {
28 cin >> oldpw;
29 cout << endl;
30 if (passwd == oldpw)
31 break;
32 else {
33 cout << "Password input error.";
34 i++;
35 }
36 if (i < 3)
37 cout << "Please enter again :";
38 else
39 cout << "Please retry later." << endl;
40 }
41 if (i < 3) {
42 cout << "Enter new password:";
43 cin >> passwd;
44 cout << '\n' << "New password has been set successfully!" << endl;
45 }
46 else
47 return;
48 }
49 void User::print_info() {
50 cout << endl << "name:" << name << endl;
51 cout << "passwd:******" << endl;
52 cout << "email:" << email << endl;
53 n++;
54 }
55 int User::n = 0;
56 void User::print_n() {
57 cout << "There are " << n << " users." << endl;
58 }
User.cpp
#include "User.hpp"
#include <iostream>
int main()
{
using namespace std;
cout << "testing 1......" << endl;
User user1("Jonny", "92197", "xyz@hotmail.com");
user1.print_info();
cout << endl
<< "testing 2......" << endl
<< endl;
User user2("Leonard");
user2.change_passwd();
user2.set_email();
user2.print_info();
User::print_n();
}
Password error
Password correct
Conclusion
1.本次实验将头文件以 .hpp 形式单独存放，作为自定义头文件，使代码更加简洁易于修改。
2.本实验需要注意的点在于：const对象只能调用const成员函数，static函数应尽量只调用static变量避免冗余。
本实验作为本学期面向对象的程序设计课程的第一个实验，难度较易，易于上手，知识点包含全面，可以很好的巩固第四第五章基础知识，作为入门实验是十分适宜的。
标签：const,cout,对象,void,Complex,实验,include,imag 来源： https://www.cnblogs.com/finimpyq-blog/p/15470013.html