实验任务1：
问题1：一共2个类，使用了标准库的string和vector
问题2：剩余成员函数基本不改变对象的值，没有必要加const，可以设置inline
问题3：初始化一个string类型的对象用于分割输出结果
实验任务2：
问题1：第一行定义并初始化一个vector类型存储int类型数据的对象，第二行定义一个vector类型的对象并复制v1的内容，第三行将v1中第一个数据值设置为-999
问题2：第一行定义并初始化一个vector类型存储vector类型数据的对象，第二行定义一个const vector类型的对象并复制v1的内容，第三行将v1中第一个vector类型对象添加一个数据-999
问题3：第一行定义一个vector类型存储int类型数据的对象t1并复制v1的第一个元素，第二行输出t1最后一个元素，第三行定义一个const vector类型存储int类型数据的对象t2并复制v2的第一个元素，第四行输出t2最后一个元素
问题4：深复制，需要
实验任务3
问题1：深复制
问题2：不能，有安全隐患，引用类型的值可能被改变
问题3：不能，assign函数需要返回引用值
实验任务4
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):lines{n},cols{m},ptr{new double[lines*cols]}{
13
14
15 }
16
17 // 构造函数，构造一个n*m的矩阵, 初始值为value
18 Matrix(int n){
19 lines=n;cols=n;
20 ptr=new double[lines*cols];
21 } // 构造函数，构造一个n*n的矩阵, 初始值为value
22 Matrix(const Matrix &x){
23 lines=x.lines;
24 cols=x.cols;
25 ptr=new double[lines*cols];
26 for(int i=0;i<lines*cols;i++){
27 ptr[i]=x.ptr[i];
28 }
29
30 }
31 // 复制构造函数， 使用已有的矩阵X构造
32 ~Matrix(){
33 delete[] ptr;
34 }
35
36 void set(const double *pvalue){
37 int i;
38 for(i=0;i<lines*cols;i++){
39 ptr[i]=pvalue[i];
40 }
41
42 } // 用pvalue指向的连续内存块数据按行为矩阵赋值
43 void clear(){
44 int i;
45 for(i=0;i<lines*cols;i++){
46 ptr[i]=0;
47 }
48 }
49 // 把矩阵对象的值置0
50
51 const double& at(int i, int j) const{
52 assert(i>=0&&i<lines&&j>=0&&j<cols);
53 return ptr[i*cols+j];
54 } // 返回矩阵对象索引(i,j)的元素const引用
55 double& at(int i, int j){
56 assert(i>=0&&i<lines&&j>=0&&j<cols);
57 return ptr[i*cols+j];
58 } // 返回矩阵对象索引(i,j)的元素引用
59
60 int get_lines() const{
61 return lines;
62 } // 返回矩阵对象行数
63 int get_cols() const{
64 return cols;
65 } // 返回矩阵对象列数
66
67 void display() const{
68 int i,j;
69
70 for(i=0;i<lines;i++){
71 cout<<ptr[i+cols];
72 for(j=1;j<cols;j++){
73 cout<<","<<ptr[i*cols+j];
74 }
75 cout<<endl;
76 }
77 cout<<endl;
78 } // 按行显示矩阵对象元素值
79
80 private:
81 int lines; // 矩阵对象内元素行数
82 int cols; // 矩阵对象内元素列数
83 double *ptr;
84 };
View Code
实验任务5
1 #pragma once
2 #include<iostream>
3 #include<string>
4 using namespace std;
5 class User{
6 private:
7 string name;
8 string password;
9 string email;
10
11 public:
12 User(string a,string b="123456",string c=""){
13 name=a;
14 password=b;
15 email=c;
16 }
17 void set_email(){
18 string x;
19 string::size_type idx;
20 string y="@";
21 cout<<"Enter email address:";
22 while(1){
23 cin>>x;
24 idx=x.find(y);
25 if(idx==string::npos)
26 cout<<"illegal email.Please re-enter email:";
27 else{
28 cout<<"email is set successfully..."<<endl;
29 email=x;
30 break;
31 }
32
33 }
34 }
35 void change_password(){
36 string x;
37 string y;
38 int i=0;
39 cout<<"Enter old password:";
40 while(i<3){
41 cin>>x;
42 if(x==password){
43 cout<<"Enter new password:";
44 cin>>y;
45 password=y;
46 cout<<"new password is set successfully..."<<endl;
47 break;
48 }
49 else{
50 i++;
51 if(i==3){
52 cout<<"password input error.Please try after a while.";
53 break;
54 }
55 cout<<"password input error.Please re-enter again:";
56
57 }
58 }
59
60
61 }
62 void display(){
63 int i;
64 cout<<"name: "<<name<<endl<<"pass: ";
65 for(i=0;i<password.size();i++){
66 cout<<"*";
67 }
68 cout<<endl<<"email: "<<email<<endl;
69 }
70
71 };
View Code
实验任务6
25.cpp:
1 #include"account.h"
2 #include<iostream>
3 using namespace std;
4 int main() {
5 Date date(2008, 11, 1);
6 SavingsAccount accounts[] = {
7 SavingsAccount(date,"03755217",0.015),
8 SavingsAccount(date,"02342342",0.015)
9
10 };
11 const int n = sizeof(accounts) / sizeof(SavingsAccount);
12 accounts[0].deposit(Date(2008, 11, 5), 5000, "salary");
13 accounts[1].deposit(Date(2008, 11, 25), 10000, "sell stock 0323");
14 accounts[0].deposit(Date(2008, 12, 5), 5500, "salary");
15 accounts[1].withdraw(Date(2008, 12, 20), 4000, "buy a laptop");
16 cout << endl;
17 for (int i = 0; i < n; i++) {
18 accounts[i].settle(Date(2009, 1, 1));
19 accounts[i].show();
20 cout << endl;
21 }
22 cout << "Total:" << SavingsAccount::getTotal() << endl;
23 return 0;
24 }
View Code
account.cpp:
1 #include"account.h"
2 #include<cmath>
3 #include<iostream>
4 using namespace std;
5 double SavingsAccount::total = 0;
6 SavingsAccount::SavingsAccount(const Date &date, const string& id, double rate)
7 :id(id), balance(0), rate(rate), lastDate(date), accumulation(0) {
8 date.show();
9 cout << "\t#" << id << "created" << endl;
10
11 }
12 void SavingsAccount::record(const Date& date, double amount, const string& desc) {
13 accumulation = accumulate(date);
14 lastDate = date;
15 amount = floor(amount * 100 + 0.5) / 100;
16 balance -= amount;
17 total += amount;
18 date.show();
19 cout << "\t#" << id << "\t" << amount << "\t" << balance << "\t" << desc << endl;
20
21 }
22 void SavingsAccount::error(const string& msg)const {
23 cout << "Error(#" << id << "):" << msg << endl;
24 }
25 void SavingsAccount::deposit(const Date &date, double amount, const string& desc){
26 record(date,amount,desc);
27 }
28 void SavingsAccount::withdraw(const Date& date, double amount, const string& desc){
29 if (amount > getBalance())
30 error("not enough money");
31 else
32 record(date,-amount,desc);
33
34 }
35 void SavingsAccount::settle(const Date& date) {
36 double interest = accumulate(date) * rate
37 / date.distance(Date(date.getYear() - 1, 1, 1));
38 if (interest != 0)
39 record(date, interest, "interest");
40 accumulation=0;
41
42 }
43 void SavingsAccount::show()const {
44 cout << id << "\tBalance:" << balance;
45 }
View Code
accounnt.h:
1 #ifndef _ _ACCOUNT_H_ _
2 #define _ _ACCOUNT_H_ _
3 #include"date.h"
4 #include<string>
5 class SavingsAccount {
6 private:
7 std::string id;
8 double balance;
9 double rate;
10 Date lastDate;
11 double accumulation;
12 static double total;
13 void record(const Date& date, double amount, const std::string& desc);
14 void error(const std::string& msg) const;
15 double accumulate(const Date& date)const {
16 return accumulation + balance * date.distance(lastDate);
17
18 }
19 public:
20 SavingsAccount(const Date& date, const std::string& id, double rate);
21 const std::string& getId()const { return id;}
22 double getBalance()const { return balance; }
23 double getRate()const { return rate; }
24 static double getTotal() { return total; }
25 void deposit(const Date& date, double amount, const std::string& desc);
26 void withdraw(const Date& date, double amount, const std::string& desc);
27 void settle(const Date& date);
28 void show()const;
29 };
30 #endif //_ _ACCOUNT_H_ _
View Code
date.cpp:
1 #include"date.h"
2 #include<iostream>
3 #include<cstdlib>
4 using namespace std;
5 namespace {
6 const int DAYS_BEFORE_MONTH[] = { 0,31,59,90,120,151,181,212,243,273,304,334,365 };
7 }
8 Date::Date(int year, int month, int day) :year(year), month(month), day(day) {
9 if (day <= 0 || day > getMaxDay()) {
10 cout << "Invalid date: ";
11 show();
12 cout << endl;
13 exit(1);
14 }
15 int years = year - 1;
16 totalDays = years * 365 + years / 4 - years / 100 + years / 400 + DAYS_BEFORE_MONTH[month - 1] + day;
17 if (isLeapYear() && month > 2)totalDays++;
18 }
19 int Date::getMaxDay()const {
20 if (isLeapYear() && month == 2)
21 return 29;
22 else
23 return DAYS_BEFORE_MONTH[month] - DAYS_BEFORE_MONTH[month - 1];
24 }
25 void Date::show()const {
26 cout << getYear() << "-" << getMonth() << "-" << getDay();
27 }
View Code
date.h:
1 class Date {
2 private:
3 int year;
4 int month;
5 int day;
6 int totalDays;
7 public:
8 Date(int year, int month, int day);
9 int getYear() const { return year; }
10 int getMonth()const { return month; }
11 int getDay()const { return day;}
12 int getMaxDay()const;
13 bool isLeapYear()const {
14 return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;}
15 void show() const;
16 int distance(const Date & date )const{
17 return totalDays - date.totalDays;
18 }
19 };
View Code
标签：const,string,int,double,date,实验,Date From： https://www.cnblogs.com/zyf-666/p/18525968