实验任务1：
代码：
1 #pragma once
2
3 #include<iostream>
4 #include<string>
5
6 using std::string;
7 using std::cout;
8
9 //按钮类
10 class Button {
11 public:
12 Button(const string& text);
13 string get_label() const;
14 void click();
15
16 private:
17 string label;
18 };
19
20 Button::Button(const string& text) :label{ text } {
21 }
22
23 inline string Button::get_label()const {
24 return label;
25 }
26
27 void Button::click() {
28 cout << "Button '" << label << "' clicked\n";
29 }
1 #pragma once
2 #include "button.hpp"
3 #include<vector>
4 #include<iostream>
5
6 using std::vector;
7 using std::cout;
8 using std::endl;
9
10 //窗口类
11 class window {
12 public:
13 window(const string& win_title);
14 void display() const;
15 void close();
16 void add_button(const string& label);
17
18 private:
19 string title;
20 vector<Button>buttons;
21 };
22
23 window::window(const string& win_title) :title{ win_title } {
24 buttons.push_back(Button("close"));
25 }
26
27 inline void window::display() const {
28 string s(40, '*');
29
30 cout << s << endl;
31 cout << "window title：" << title << endl;
32 cout << "It has " << buttons.size() << " buttons："<<endl;
33 for (const auto& i : buttons)
34 cout << i.get_label() << " button " << endl;
35 cout << s << endl;
36 }
37
38 void window::close() {
39 cout << "close window '" << title << "'" << endl;
40 buttons.at(0).click();
41 }
42
43 void window::add_button(const string& label) {
44 buttons.push_back(Button(label));
45 }
1 #define _CRT_SECURE_NO_WARNINGS 1
2
3 #include "window.hpp"
4 #include<iostream>
5
6 using std::cout;
7 using std::cin;
8
9 void test() {
10 window w1("new window");
11 w1.add_button("maximize");
12 w1.display();
13 w1.close();
14 }
15
16 int main() {
17 cout << "用组合类模拟简单GUI：\n";
18 test();
19 }
截图：
问题1：
两个类（button和window）vector,string.button和string，window和button以及string以及vector.
问题2：
不合适。因为加了const之后不可修改，加了inline是为了提高效率，对于较复杂的程序随意加上这两个关键字可能会出错。
问题3：
创建1个string s，内容是40个*，分开各部分代码。
实验任务2：
代码：
1 #define _CRT_SECURE_NO_WARNINGS 1
2
3 #include<iostream>
4 #include<vector>
5
6 using namespace std;
7
8 void output1(const vector<int>& v) {
9 for (auto& i : v) {
10 cout << i << ", ";
11 }
12 cout << "\b\b \n";
13 }
14
15 void output2(const vector<vector<int>> v) {
16 for (auto& i : v) {
17 for (auto& j : i) {
18 cout << j << ", ";
19 }
20 cout << "\b\b \n";
21 }
22 }
23
24 void test1() {
25 vector<int> v1(5, 42);
26 const vector<int> v2(v1);
27
28 v1.at(0) = -999;
29 cout << "v1: "; output1(v1);
30 cout << "v2: "; output1(v2);
31 cout << "v1.at(0) = " << v1.at(0) << endl;
32 cout << "v2.at(0) = " << v2.at(0) << endl;
33 }
34
35 void test2() {
36 vector<vector<int>>v1{ {1,2,3},{4,5,6,7} };
37 const vector<vector<int>> v2(v1);
38
39 v1.at(0).push_back(-999);
40 cout << "v1: \n"; output2(v1);
41 cout << "v2: \n"; output2(v2);
42
43 vector<int>t1 = v1.at(0);
44 cout << t1.at(t1.size() - 1) << endl;
45
46 const vector<int>t2 = v2.at(0);
47 cout << t2.at(t2.size() - 1) << endl;
48 }
49
50 int main() {
51 cout << "测试1:\n";
52 test1();
53
54 cout << "\n测试2;\n";
55 test2();
56 }
截图：
问题1：
21：创建一个元素为整型的可变长数组v1，元素是5个42；
22：创建一个元素为整型的可变长数组v2，元素与v1相同，是5个42；
24：将v1的第一个数改为-999.
问题2：
创建一个元素为元素是可变长数组容器的可变长数组容器v1，元素是{1，2，3}和{4，5，6，7}；
创建一个元素为元素是可变长数组容器的可变长数组容器v2，深复制v1，元素是{1，2，3}和{4，5，6，7}；
将v1第一个元素中的第一个元素改为-999；
问题3：
39，42：得到当前数组的第一个元素；
40，43：输出当前数组的最后一个元素。
问题4：
深复制；需要。
实验任务3：
代码：
1 #pragma once
2
3 #include<iostream>
4 #include<cassert>
5
6 using std::cout;
7 using std::endl;
8
9 //动态int数组对象类
10 class vectorInt {
11 public:
12 vectorInt(int n);
13 vectorInt(int n, int value);
14 vectorInt(const vectorInt& vi);
15 ~vectorInt();
16
17 int& at(int index);
18 const int& at(int index) const;
19
20 vectorInt& assign(const vectorInt& v);
21 int get_size() const;
22
23 private:
24 int size;
25 int* ptr; //ptr指向包含size个int的数组
26 };
27
28 vectorInt::vectorInt(int n) :size{ n }, ptr{ new int[size] } {
29 }
30
31 vectorInt::vectorInt(int n,int value) :size{ n }, ptr{ new int[size] } {
32 for (auto i = 0; i < size; i++) {
33 ptr[i] = value;
34 }
35 }
36
37 vectorInt::vectorInt(const vectorInt& vi) :size{ vi.size }, ptr{ new int[size] } {
38 for (auto i = 0; i < size; i++) {
39 ptr[i] = vi.ptr[i];
40 }
41 }
42
43 vectorInt::~vectorInt() {
44 delete[] ptr;
45 }
46
47 const int& vectorInt::at(int index)const {
48 assert(index >= 0 && index < size);
49
50 return ptr[index];
51 }
52
53 int& vectorInt::at(int index){
54 assert(index >= 0 && index < size);
55
56 return ptr[index];
57 }
58
59 vectorInt& vectorInt::assign(const vectorInt& v) {
60 delete[] ptr; //释放对象中ptr原本指向的资源
61
62 size = v.size;
63 ptr = new int[size];
64
65 for (int i = 0; i < size; i++) {
66 ptr[i] = v.ptr[i];
67 }
68
69 return *this;
70 }
71
72 int vectorInt::get_size()const {
73 return size;
74 }
1 #define _CRT_SECURE_NO_WARNINGS 1
2
3 #include"vectorInt.hpp"
4 #include<iostream>
5
6 using std::cin;
7 using std::cout;
8
9 void output(const vectorInt& vi) {
10 for (auto i = 0; i < vi.get_size(); i++) {
11 cout << vi.at(i) << ", ";
12 }
13 cout << "\b\b\n";
14 }
15
16
17 void test1() {
18 int n;
19 cout << "Enter n: ";
20 cin >> n;
21
22 vectorInt x1(n);
23 for (auto i = 0; i < n; i++) {
24 x1.at(i) = i * i;
25 }
26 cout << "x1: "; output(x1);
27
28 vectorInt x2(n, 42);
29 vectorInt x3(x2);
30 x2.at(0) = -999;
31 cout << "x2: ";output(x2);
32 cout << "x3: "; output(x3);
33 }
34
35 void test2() {
36 const vectorInt x(5, 42);
37 vectorInt y(10, 0);
38
39 cout << "y: "; output(y);
40 y.assign(x);
41 cout << "y: "; output(y);
42
43 cout << "x.at(0) = " << x.at(0) << endl;
44 cout << "y.at(0) = " << y.at(0) << endl;
45 }
46
47 int main() {
48 cout << "测试1：\n";
49 test1();
50
51 cout << "\n测试2：\n";
52 test2();
53 }
截图：
问题1：
深复制。
问题2：
不能。会有。
返回int，不能被赋值。
const去掉后，值可能被修改。
问题3：
可以。返回引用用引用接收，返回vectorInt用对象接收，是可以的。
实验任务4：
代码：
1 #pragma once
2
3 #include<iostream>
4 #include<cassert>
5
6 using std::cout;
7 using std::endl;
8
9 //类Matrix的声明
10 class Matrix {
11 public:
12 Matrix(int n, int m);
13 Matrix(int n);
14 Matrix(const Matrix& x);
15 ~Matrix();
16
17 void set(const double *pvalue);
18 void clear();
19
20 const double& at(int i,int j)const;
21 double& at(int i, int j);
22
23 int get_lines()const;
24 int get_cols()const;
25
26 void display()const;
27 private:
28 int lines;
29 int cols;
30 double* ptr;
31 };
32
33 Matrix::Matrix(int n, int m) :lines{ n }, cols{ m }, ptr{ new double[lines * cols] } {
34 for (int i = 0; i < n * m; i++) {
35 ptr[i] = 1;//设value为1
36 }
37 }
38
39 Matrix::Matrix(int n) :lines{ n }, cols{ n }, ptr{ new double[n * n] } {
40 for (int i = 0; i < n * n; i++) {
41 ptr[i] = 1;
42 }
43 }
44
45 Matrix::Matrix(const Matrix &x):lines{ x.lines }, cols{ x.cols }, ptr{ new double[lines*cols] } {
46 for (int i = 0; i < lines*cols; i++) {
47 ptr[i] = x.ptr[i];
48 }
49 }
50
51 Matrix::~Matrix() {
52 delete[] ptr;
53 }
54
55 void Matrix::set(const double *pvalue) {
56 for (int i = 0; i < lines * cols; i++) {
57 ptr[i] = pvalue[i];
58 }
59 }
60
61 void Matrix::clear() {
62 for (int i = 0; i < lines * cols; i++) {
63 ptr[i] = 0;
64 }
65 }
66
67 const double& Matrix::at(int i, int j)const {
68 return ptr[i*cols+j];
69 }
70 double& Matrix::at(int i, int j) {
71 return ptr[i * cols + j];
72 }
73
74 int Matrix::get_lines()const {
75 return lines;
76 }
77 int Matrix::get_cols()const {
78 return cols;
79 }
80
81 void Matrix::display()const {
82 for (int i = 0; i < lines; i++) {
83 for (int j = 0; j < cols; j++) {
84 cout << ptr[i * cols + j]<<", ";
85 }
86 cout << endl;
87 }
88 }
1 #define _CRT_SECURE_NO_WARNINGS 1
2
3 #include "matrix.hpp"
4 #include <iostream>
5 #include <cassert>
6
7 using std::cin;
8 using std::cout;
9 using std::endl;
10
11
12 const int N = 1000;
13
14 // 输出矩阵对象索引为index所在行的所有元素
15 void output(const Matrix& m, int index) {
16 assert(index >= 0 && index < m.get_lines());
17
18 for (auto j = 0; j < m.get_cols(); ++j)
19 cout << m.at(index, j) << ", ";
20 cout << "\b\b \n";
21 }
22
23
24 void test1() {
25 double x[1000] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
26
27 int n, m;
28 cout << "Enter n and m: ";
29 cin >> n >> m;
30
31 Matrix m1(n, m); // 创建矩阵对象m1, 大小n×m
32 m1.set(x); // 用一维数组x的值按行为矩阵m1赋值
33
34 Matrix m2(m, n); // 创建矩阵对象m1, 大小m×n
35 m2.set(x); // 用一维数组x的值按行为矩阵m1赋值
36
37 Matrix m3(2); // 创建一个2×2矩阵对象
38 m3.set(x); // 用一维数组x的值按行为矩阵m4赋值
39
40 cout << "矩阵对象m1: \n"; m1.display(); cout << endl;
41 cout << "矩阵对象m2: \n"; m2.display(); cout << endl;
42 cout << "矩阵对象m3: \n"; m3.display(); cout << endl;
43 }
44
45 void test2() {
46 Matrix m1(2, 3);
47 m1.clear();
48
49 const Matrix m2(m1);
50 m1.at(0, 0) = -999;
51
52 cout << "m1.at(0, 0) = " << m1.at(0, 0) << endl;
53 cout << "m2.at(0, 0) = " << m2.at(0, 0) << endl;
54 cout << "矩阵对象m1第0行: "; output(m1, 0);
55 cout << "矩阵对象m2第0行: "; output(m2, 0);
56 }
57
58 int main() {
59 cout << "测试1: \n";
60 test1();
61
62 cout << "测试2: \n";
63 test2();
64 }
截图：
实验任务5：
代码：
1 #pragma once
2
3 #include<string>
4 #include<iostream>
5
6 using namespace std;
7
8 class User{
9 public:
10 User(const string name1) :name{ name1 } {
11 password = "123456";
12 }
13 User(const string name1, const string password1, const string email1) :name{ name1 }, password{ password1 }, email{ email1 } {
14 }
15 void set_email();
16 void change_password();
17 void display();
18 bool isTrueEmail(string newEmail);
19 private:
20 string name;
21 string password;
22 string email;
23 };
24
25 void User::set_email() {
26 cout << "Enter email address：";
27 string newEmail;
28 cin >> newEmail;
29 while(!isTrueEmail(newEmail)) {
30 cout << "illegal email. Please re-enter email: ";
31 cin >> newEmail;
32 }
33 cout << "email is set successfully..." << endl;
34 email = newEmail;
35 }
36
37 bool User::isTrueEmail(string newEmail) {
38 for (int i = 0; i < newEmail.size(); i++) {
39 if (newEmail[i]=='@') {
40 return true;
41 }
42 }
43 return false;
44 }
45
46 void User::change_password() {
47 cout << "Enter old password: ";
48 string newPassword;
49 cin >> newPassword;
50 int count = 0;//count记录输入密码错误的次数
51 while (newPassword != password) {
52 count++;
53 cout << "password input error. ";
54 if (count == 3) {
55 cout << "Please try after a while." << endl;
56 return;
57 }
58 cout<<"Please re-enter again : ";
59 cin >> newPassword;
60 }
61 cout << "Enter new password: ";
62 cin >> newPassword;
63 password = newPassword;
64 cout << "new password is set successfully..." << endl;
65 }
66
67 void User::display() {
68 cout << "name: " << name << endl;
69 cout << "pass: ";
70 for (int i = 0; i < password.size(); i++) {
71 cout << "*";
72 }
73 cout << endl;
74 cout << "email " << email << endl;
75 }
1 #define _CRT_SECURE_NO_WARNINGS 1
2
3 #include "user.hpp"
4 #include <iostream>
5 #include <vector>
6 #include <string>
7
8 using std::cin;
9 using std::cout;
10 using std::endl;
11 using std::vector;
12 using std::string;
13
14 void test() {
15 vector<User> user_lst;
16
17 User u1("Alice", "2024113", "[email protected]");
18 user_lst.push_back(u1);
19 cout << endl;
20
21 User u2("Bob");
22 u2.set_email();
23 u2.change_password();
24 user_lst.push_back(u2);
25 cout << endl;
26
27 User u3("Hellen");
28 u3.set_email();
29 u3.change_password();
30 user_lst.push_back(u3);
31 cout << endl;
32
33 cout << "There are " << user_lst.size() << " users. they are: " << endl;
34 for (auto& i : user_lst) {
35 i.display();
36 cout << endl;
37 }
38 }
39
40 int main() {
41 test();
42 }
截图：
实验任务6：
代码：
1 #ifndef __DATE_H__
2 #define __DATE_H__
3 class Date {
private:
int year;
int month;
int day;
int totalDays;
public:
Date(int year, int month, int day);
int getYear() const { return year; }
int getMonth() const { return month; }
int getDay() const { return day; }
int getMaxDay() const;
bool isLeapYear() const {
return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
}
void show() const;
int distance(const Date& date) const {
return totalDays - date.totalDays;
}
};
#endif //__DATE_H__
#include "date.h"
#include <iostream>
#include <cstdlib>
using namespace std;
namespace {
const int DAYS_BEFORE_MONTH[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 };
}
Date::Date(int year, int month, int day) : year(year), month(month), day(day) {
if (day <= 0 || day > getMaxDay()) {
cout << "Invalid date: ";
show();
cout << endl;
exit(1);
}
int years = year - 1;
totalDays = years * 365 + years / 4 - years / 100 + years / 400
+ DAYS_BEFORE_MONTH[month - 1] + day;
if (isLeapYear() && month > 2) totalDays++;
}
int Date::getMaxDay() const {
if (isLeapYear() && month == 2)
return 29;
else
return DAYS_BEFORE_MONTH[month]- DAYS_BEFORE_MONTH[month - 1];
}
void Date::show() const {
cout << getYear() << "-" << getMonth() << "-" << getDay();
}
#ifndef __ACCOUNT_H__
#define __ACCOUNT_H__
#include "date.h"
#include <string>
class SavingsAccount {
private:
std::string id;
double balance;
double rate;
Date lastDate;
double accumulation;
static double total;
void record(const Date &date, double amount, const std::string &desc);
void error(const std::string &msg) const;
double accumulate(const Date& date) const {
return accumulation + balance * date.distance(lastDate);
}
public:
SavingsAccount(const Date &date, const std::string &id, double rate);
const std::string &getId() const { return id; }
double getBalance() const { return balance; }
double getRate() const { return rate; }
static double getTotal() { return total; }
void deposit(const Date &date, double amount, const std::string &desc);
void withdraw(const Date &date, double amount, const std::string &desc);
void settle(const Date &date);
void show() const;
};
#endif //__ACCOUNT_H__
#include "account.h"
#include <cmath>
#include <iostream>
using namespace std;
double SavingsAccount::total = 0;
SavingsAccount::SavingsAccount(const Date &date, const string &id, double rate)
: id(id), balance(0), rate(rate), lastDate(date), accumulation(0) {
date.show();
cout << "\t#" << id << " created" << endl;
}
void SavingsAccount::record(const Date &date, double amount, const string &desc) {
accumulation = accumulate(date);
lastDate = date;
amount = floor(amount * 100 + 0.5) / 100;
balance += amount;
total += amount;
date.show();
cout << "\t#" << id << "\t" << amount << "\t" << balance << "\t" << desc << endl;
}
void SavingsAccount::error(const string &msg) const {
cout << "Error(#" << id << "): " << msg << endl;
}
void SavingsAccount::deposit(const Date &date, double amount, const string &desc) {
record(date, amount, desc);
}
void SavingsAccount::withdraw(const Date &date, double amount, const string &desc) {
if (amount > getBalance())
error("not enough money");
else
record(date, -amount, desc);
}
void SavingsAccount::settle(const Date &date) {
double interest = accumulate(date) * rate
/ date.distance(Date(date.getYear() - 1, 1, 1));
if (interest != 0)
record(date, interest, "interest");
accumulation = 0;
}
void SavingsAccount::show() const {
cout << id << "\tBalance: " << balance;
}
#include "account.h"
#include <iostream>
using namespace std;
int main() {
Date date(2008, 11, 1);
SavingsAccount accounts[] = {
SavingsAccount(date, "03755217", 0.015),
SavingsAccount(date, "02342342", 0.015)
};
const int n = sizeof(accounts) / sizeof(SavingsAccount);
accounts[0].deposit(Date(2008, 11, 5), 5000, "salary");
accounts[1].deposit(Date(2008, 11, 25), 10000, "sell stock 0323");
accounts[0].deposit(Date(2008, 12, 5), 5500, "salary");
accounts[1].withdraw(Date(2008, 12, 20), 4000, "buy a laptop");
cout << endl;
for (int i = 0; i < n; i++) {
accounts[i].settle(Date(2009, 1, 1));
accounts[i].show();
cout << endl;
}
cout << "Total: " << SavingsAccount::getTotal() << endl;
return 0;
}
截图：
标签：std,const,cout,对象,void,int,实验,string From： https://www.cnblogs.com/yian135/p/18538571