实验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
28
29
30 #include "window.hpp"
31 #include <iostream>
32
33 using std::cout;
34 using std::cin;
35
36 void test() {
37 Window w1("new window");
38 w1.add_button("maximize");
39 w1.display();
40 w1.close();
41 }
42
43 int main() {
44 cout << "用组合类模拟简单GUI:\n";
45 test();
46 }
47
48
49
50
51 #pragma once
52 #include "button.hpp"
53 #include <vector>
54 #include <iostream>
55
56 using std::vector;
57 using std::cout;
58 using std::endl;
59
60 // 窗口类
61 class Window{
62 public:
63 Window(const string &win_title);
64 void display() const;
65 void close();
66 void add_button(const string &label);
67
68 private:
69 string title;
70 vector<Button> buttons;
71 };
72
73 Window::Window(const string &win_title): title{win_title} {
74 buttons.push_back(Button("close"));
75 }
76
77 inline void Window::display() const {
78 string s(40, '*');
79
80 cout << s << endl;
81 cout << "window title: " << title << endl;
82 cout << "It has " << buttons.size() << " buttons: " << endl;
83 for(const auto &i: buttons)
84 cout << i.get_label() << " button" << endl;
85 cout << s << endl;
86 }
87
88 void Window::close() {
89 cout << "close window '" << title << "'" << endl;
90 buttons.at(0).click();
91 }
92
93 void Window::add_button(const string &label) {
94 buttons.push_back(Button(label));
95 }
View Code
运行截图：
问题1：自定义两个类，按钮类和窗口类，标准库使用了vector类，窗口类和vector类进行了组合
问题2：不适合，const类型函数为常量函数，无法对其值进行改变，而inline为内联函数，强行将
其他函数转化为内联函数可能会导致运行时间增加
问题3：将字符串s赋值为40个*
实验2代码：
1 #include <iostream>
2 #include <vector>
3
4 using namespace std;
5
6 void output1(const vector<int> &v) {
7 for(auto &i: v)
8 cout << i << ", ";
9 cout << "\b\b \n";
10 }
11
12 void output2(const vector<vector<int>> v) {
13 for(auto &i: v) {
14 for(auto &j: i)
15 cout << j << ", ";
16 cout << "\b\b \n";
17 }
18 }
19
20 void test1() {
21 vector<int> v1(5, 42);
22 const vector<int> v2(v1);
23
24 v1.at(0) = -999;
25 cout << "v1: "; output1(v1);
26 cout << "v2: "; output1(v2);
27 cout << "v1.at(0) = " << v1.at(0) << endl;
28 cout << "v2.at(0) = " << v2.at(0) << endl;
29 }
30
31 void test2() {
32 vector<vector<int>> v1{{1, 2, 3}, {4, 5, 6, 7}};
33 const vector<vector<int>> v2(v1);
34
35 v1.at(0).push_back(-999);
36 cout << "v1: \n"; output2(v1);
37 cout << "v2: \n"; output2(v2);
38
39 vector<int> t1 = v1.at(0);
40 cout << t1.at(t1.size()-1) << endl;
41
42 const vector<int> t2 = v2.at(0);
43 cout << t2.at(t2.size()-1) << endl;
44 }
45
46 int main() {
47 cout << "测试1:\n";
48 test1();
49
50 cout << "\n测试2:\n";
51 test2();
52 }
View Code
运行截图：
问题1：创建一个含有5个int类型的元素的动态数组v1，值为42，将v1复制给v2，将v1的第一个元素赋值为-999
问题2：创建一个含有两个元素类型为int的动态数组的动态数组v1，将v1复制给v2，v1的第一个数组末尾插入-999
问题3：创建一个动态数组t1，将v1的第一个数组赋值给他，输出t1中第四个元素，创建一个动态数组t2，将v2的第一个数组赋值给他，输出t2中第三个元素
问题4：深复制，不需要
实验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 vectorInt::vectorInt(const vectorInt &vi): size{vi.size}, ptr{new int[size]} {
37 for(auto i = 0; i < size; ++i)
38 ptr[i] = vi.ptr[i];
39 }
40
41 vectorInt::~vectorInt() {
42 delete [] ptr;
43 }
44
45 const int& vectorInt::at(int index) const {
46 assert(index >= 0 && index < size);
47
48 return ptr[index];
49 }
50
51 int& vectorInt::at(int index) {
52 assert(index >= 0 && index < size);
53
54 return ptr[index];
55 }
56
57
58
59
60
61 #include "vectorInt.hpp"
62 #include <iostream>
63
64 using std::cin;
65 using std::cout;
66
67 void output(const vectorInt &vi) {
68 for(auto i = 0; i < vi.get_size(); ++i)
69 cout << vi.at(i) << ", ";
70 cout << "\b\b \n";
71 }
72
73
74 void test1() {
75 int n;
76 cout << "Enter n: ";
77 cin >> n;
78
79 vectorInt x1(n);
80 for(auto i = 0; i < n; ++i)
81 x1.at(i) = i*i;
82 cout << "x1: "; output(x1);
83
84 vectorInt x2(n, 42);
85 vectorInt x3(x2);
86 x2.at(0) = -999;
87 cout << "x2: "; output(x2);
88 cout << "x3: "; output(x3);
89 }
90
91 void test2() {
92 const vectorInt x(5, 42);
93 vectorInt y(10, 0);
94
95 cout << "y: "; output(y);
96 y.assign(x);
97 cout << "y: "; output(y);
98
99 cout << "x.at(0) = " << x.at(0) << endl;
100 cout << "y.at(0) = " << y.at(0) << endl;
101 }
102
103 int main() {
104 cout << "测试1: \n";
105 test1();
106
107 cout << "\n测试2: \n";
108 test2();
109 }
View Code
运行截图：
问题1：深复制
问题2：不能正确运行，有，如果返回值是引用变量可能会改变数组中元素的值
实验4代码:
1 #pragma once
2
3 #include <cassert>
4 #include <iostream>
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); // 构造函数，构造一个n*m的矩阵, 初始值为value
13 Matrix(int n); // 构造函数，构造一个n*n的矩阵, 初始值为value
14 Matrix(const Matrix &x); // 复制构造函数， 使用已有的矩阵X构造
15 ~Matrix();
16
17 void set(const double *pvalue); // 用pvalue指向的连续内存块数据按行为矩阵赋值
18 void clear(); // 把矩阵对象的值置0
19
20 const double &at(int i, int j) const; // 返回矩阵对象索引(i,j)的元素const引用
21 double &at(int i, int j); // 返回矩阵对象索引(i,j)的元素引用
22
23 int get_lines() const; // 返回矩阵对象行数
24 int get_cols() const; // 返回矩阵对象列数
25
26 void display() const; // 按行显示矩阵对象元素值
27
28 private:
29 int lines; // 矩阵对象内元素行数
30 int cols; // 矩阵对象内元素列数
31 double *ptr;
32 };
33
34 // 类Matrix的实现：待补足
35 Matrix::Matrix(int n, int m) : lines(n), cols(m) {
36 ptr = new double[n * m];
37 clear();
38 }
39
40 Matrix::Matrix(int n) : Matrix(n, n) {}
41
42 Matrix::Matrix(const Matrix &x) : lines(x.lines), cols(x.cols) {
43 ptr = new double[lines * cols];
44 for (int i = 0; i < lines * cols; i++)
45 ptr[i] = x.ptr[i];
46 }
47
48 Matrix::~Matrix() {
49 delete[] ptr;
50 }
51
52 void Matrix::set(const double *pvalue) {
53 for (int i = 0; i < lines * cols; i++)
54 ptr[i] = pvalue[i];
55 }
56
57 void Matrix::clear() {
58 for (int i = 0; i < lines * cols; i++)
59 ptr[i] = 0;
60 }
61
62 const double &Matrix::at(int i, int j) const {
63 if(i >= 0 && i < lines && j >= 0 && j < cols)
64 return ptr[i * cols + j];
65 }
66
67 double &Matrix::at(int i, int j) {
68 if(i >= 0 && i < lines && j >= 0 && j < cols)
69 return ptr[i * cols + j];
70 }
71
72 int Matrix::get_lines() const {
73 return lines;
74 }
75
76 int Matrix::get_cols() const {
77 return cols;
78 }
79
80 void Matrix::display() const {
81 for (int i = 0; i < lines; i++) {
82 for (int j = 0; j < cols; j++) {
83 cout << ptr[i * cols + j] << " ";
84 }
85 cout << endl;
86 }
87 }
88
89
90
91
92
93 #include "matrix.hpp"
94 #include <cassert>
95 #include <iostream>
96 #include <numeric>
97
98 using std::cin;
99 using std::cout;
100 using std::endl;
101
102 const int N = 1000;
103
104 // 输出矩阵对象索引为index所在行的所有元素
105 void output(const Matrix &m, int index) {
106 assert(index >= 0 && index < m.get_lines());
107
108 for (auto j = 0; j < m.get_cols(); ++j)
109 cout << m.at(index, j) << ", ";
110 cout << "\b\b \n";
111 }
112
113 void test1() {
114 double x[1000];
115
116 std::iota(x, x + N, 1); // 用1到N初始化数组x
117
118 int n, m;
119 cout << "Enter n and m: ";
120 cin >> n >> m;
121
122 Matrix m1(n, m); // 创建矩阵对象m1, 大小n×m
123 m1.set(x); // 用一维数组x的值按行为矩阵m1赋值
124
125 Matrix m2(m, n); // 创建矩阵对象m1, 大小m×n
126 m2.set(x); // 用一维数组x的值按行为矩阵m1赋值
127
128 Matrix m3(2); // 创建一个2×2矩阵对象
129 m3.set(x); // 用一维数组x的值按行为矩阵m4赋值
130
131 cout << "矩阵对象m1: \n";
132 m1.display();
133 cout << endl;
134 cout << "矩阵对象m2: \n";
135 m2.display();
136 cout << endl;
137 cout << "矩阵对象m3: \n";
138 m3.display();
139 cout << endl;
140 }
141
142 void test2() {
143 Matrix m1(2, 3);
144 m1.clear();
145
146 const Matrix m2(m1);
147 m1.at(0, 0) = -999;
148
149 cout << "m1.at(0, 0) = " << m1.at(0, 0) << endl;
150 cout << "m2.at(0, 0) = " << m2.at(0, 0) << endl;
151 cout << "矩阵对象m1第0行: ";
152 output(m1, 0);
153 cout << "矩阵对象m2第0行: ";
154 output(m2, 0);
155 }
156
157 int main() {
158 cout << "测试1: \n";
159 test1();
160
161 cout << "测试2: \n";
162 test2();
163 }
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实验5代码：
1 #pragma once
2
3 #include<iostream>
4 #include<string>
5
6 using namespace std;
7
8
9 class User{
10 public:
11 User(string Name);
12 User(string Name,string Password,string Email);
13 ~User();
14 void set_email();
15 void change_password();
16 void display();
17 private:
18 string name,password="123456",email="[email protected]";
19 };
20 User::User(string Name){
21 name=Name;
22 }
23
24 User::~User()=default;
25
26 User::User(string Name,string Password,string Email){
27 name=Name;
28 password=Password;
29 email=Email;
30 }
31
32
33
34 void User::set_email(){
35 string v;
36 int x=0;
37 cout<<"请输入邮箱地址：";
38 cin>>v;
39 for(auto i:v){
40 if(i=='@'){
41 x=1;
42 break;
43 }
44 }
45 while(!x){
46 cout<<"请输入有效邮箱地址：";
47 cin>>v;
48 for(auto i:v){
49 if(i=='@'){
50 x=1;
51 break;
52 }
53 }
54 }
55 email=v;
56 cout<<"邮箱已成功设置!"<<endl<<endl;
57 }
58
59
60 void User::change_password(){
61 string v1,v2;
62 int t=0;
63 cout<<"请输入旧密码：";
64 cin>>v1;
65 if(v1==password){
66 cout<<"请输入新密码：";
67 cin>>v2;
68 password=v2;
69 }
70 else{
71 cout<<"密码错误!"<<endl<<endl;
72 t++;
73 while(t<3){
74 cout<<"请输入旧密码：";
75 cin>>v1;
76 if(v1==password)
77 break;
78 t++;
79 cout<<"密码错误!"<<endl<<endl;
80 }
81 if(t>=3){
82 cout<<"请稍后再试"<<endl<<endl;
83 return;
84 }
85 else{
86 cout<<"请输入新密码：";
87 cin>>v2;
88 password=v2;
89 }
90 }
91 cout<<"密码已修改完成！"<<endl<<endl;
92 }
93
94
95 void User::display(){
96 cout<<name<<endl;
97 for(auto i:password)
98 cout<<'*';
99 cout<<endl;
100 cout<<email<<endl;
101 }
102
103
104
105
106 #include "user.hpp"
107 #include <iostream>
108 #include <string>
109 #include <vector>
110
111 using std::cin;
112 using std::cout;
113 using std::endl;
114 using std::string;
115 using std::vector;
116
117 void test() {
118 vector<User> user_lst;
119
120 User u1("Alice", "2024113", "[email protected]");
121 user_lst.push_back(u1);
122 cout << endl;
123
124 User u2("Bob");
125 u2.set_email();
126 u2.change_password();
127 user_lst.push_back(u2);
128 cout << endl;
129
130 User u3("Hellen");
131 u3.set_email();
132 u3.change_password();
133 user_lst.push_back(u3);
134 cout << endl;
135
136 cout << "There are " << user_lst.size() << " users. they are: " << endl;
137 for (auto &i : user_lst) {
138 i.display();
139 cout << endl;
140 }
141 }
142
143 int main() { test(); }
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实验6代码：
1 #pragma once
2 class Date {
3 private:
4 int year;
5 int month;
6 int day;
7 int totalDays;
8 public:
9 Date(int year, int month, int day);
10 int getYear()const { return year; }
11 int getMonth()const { return month; }
12 int getDay()const { return day; }
13 int getMaxDay()const;
14 bool isLeapYear()const {
15 return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
16 }
17 void show() const;
18 int distance(const Date& date)const {
19 return totalDays - date.totalDays;
20 }
21 };
22
23
24
25 #include "date.h"
26 #include <iostream>
27 #include <cstdlib>
28 using namespace std;
29 namespace {
30 //namespace使下面的定义只在当前文件中有效
31 const int DAYS_BEFORE_MONTH[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 356 };
32 }
33 Date::Date(int year, int month, int day) :year(year), month(month), day(day) {
34 if (day <= 0 || day > getMaxDay()) {
35 cout << "Invalid date: ";
36 show();
37 cout << endl;
38 exit(1);
39 }
40 int years = year - 1;
41 totalDays = years * 365 + years / 4 - years / 100 + years / 400 + DAYS_BEFORE_MONTH[month - 1] + day;
42 if (isLeapYear() && month > 2) totalDays++;
43 }
44 int Date::getMaxDay() const {
45 if (isLeapYear() && month == 2) return 29;
46 else return DAYS_BEFORE_MONTH[month] - DAYS_BEFORE_MONTH[month - 1];
47 }
48 void Date::show() const {
49 cout << getYear() << "-" << getMonth() << "-" << getDay();
50 }
51
52
53
54 #ifndef __ACCOUNT_H__
55 #define __ACCOUNT_H__
56 #include "date.h"
57 #include <string>
58 class SavingsAccount {//储蓄账户类
59 private:
60 std::string id;//账号
61 double balance;//余额
62 double rate;//存款的年利率
63 Date lastDate;//上次变更余额的时期
64 double accumulation;//按日累加以和
65 static double total;//所有账户的总金额
66 //记录一笔账，date为日期，amount为金额，desc为说明
67 void record(const Date & date, double amount, const std::string & desc);
68 //报告错误信息
69 void error(const std::string & msg) const;
70 //获得指定日期为止的存款金额按日累增值
71 double accumulate(const Date & date) const {
72 return accumulation + balance * date.distance(lastDate);
73 }
74 public:
75 //构造函数
76 SavingsAccount(const Date & date, const std::string & id, double rate);//获得账号
77 const std::string & getId() const { return id; } //获得余额
78 double getBalance() const { return balance; } //获得年利率
79 double getRate() const { return rate; }
80 static double getTotal() { return total; }//存入现金
81 void deposit(const Date & date, double amount, const std::string & desc);//取出现金
82 void withdraw(const Date & date, double amount, const std::string & desc);//结算利息，每年1月1日调用一次该函数
83 void settle(const Date & date);
84 //显示账户信息
85 void show() const;
86 };
87 #endif //__ACCOUNT_H__#pragma once
88
89
90
91
92 #include "account.h"
93 #include <cmath>
94 #include <iostream>
95 using namespace std;
96 double SavingsAccount::total = 0;
97 //SavingsAccount类相关成员函数的实现
98 SavingsAccount::SavingsAccount(const Date &date,const string &id,double rate):id(id),balance(0),rate(rate),lastDate(date),accumulation(0){
99 date.show();
100 cout << "\t#" << id << " created" << endl;
101 }
102 void SavingsAccount::record(const Date & date, double amount, const string & desc) {
103 accumulation = accumulate(date);
104 lastDate = date;
105 amount = floor(amount * 100 + 0.5) / 100;
106 //保留小数点后两位
107 balance += amount;
108 total += amount;
109 date.show();
110 cout << "\t#" << id << "\t" << amount << "\t" << balance << "\t" << desc << endl;
111 }
112 void SavingsAccount::error(const string & msg) const {
113 cout << "Error(#" << id << "): " << msg << endl;
114 }
115 void SavingsAccount::deposit(const Date & date, double amount, const string & desc) {
116 record(date, amount, desc);
117 }
118 void SavingsAccount::withdraw(const Date & date, double amount, const string & desc) {
119 if (amount > getBalance())
120 error("not enough money");
121 else
122 record(date, -amount, desc);
123 }
124 void SavingsAccount::settle(const Date & date) {
125 double interest = accumulate(date) * rate / date.distance(Date(date.getYear() - 1, 1, 1));
126 if (interest != 0)
127 record(date, interest, "interest");
128 accumulation = 0;
129 }
130 void SavingsAccount::show() const {
131 cout << "ID: " << id << "\tBalance: " << balance;
132 }
133
134
135
136
137 #include "account.h"
138 #include <iostream>
139 using namespace std;
140 int main() {
141 Date date(2008, 11, 1);
142 //起始日期
143 //建立几个账户
144 SavingsAccount accounts[] = {
145 SavingsAccount(date, "03755217", 0.015),
146 SavingsAccount(date, "02342342", 0.015)
147 };
148 //几笔账目
149 accounts[0].deposit(Date(2008, 11, 5), 5000, "salary");
150 accounts[1].deposit(Date(2008, 11, 25), 10000, "sell stock 0323");
151 accounts[0].deposit(Date(2008, 12, 5), 5500, "salary");
152 accounts[1].withdraw(Date(2008, 12, 20), 4000, "buy a laptop");
153 //结算所有账户并输出各个账户信息
154 cout << endl;
155 for (int i = 0; i < sizeof(accounts) / sizeof(SavingsAccount); i++) {
156 accounts[i].settle(Date(2009, 1, 1));
157 accounts[i].show();
158 cout << endl;
159 }
160 cout << "Total: " << SavingsAccount::getTotal() << endl;
161 return 0;
162 }
View Code
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标签：std,const,cout,int,void,实验,string From： https://www.cnblogs.com/ywq121/p/18525839