任务一
task1.cpp
button.hpp #pragma once #include <iostream> #include <string> using std::string; using std::cout; // 按钮类 class Button { public: Button(const string &text); string get_label() const; void click(); private: string label; }; Button::Button(const string &text): label{text} {} inline string Button::get_label() const { return label; } void Button::click() { cout << "Button '" << label << "' clicked\n"; } window.hpp #pragma once #include "button.hpp" #include <vector> #include <iostream> using std::vector; using std::cout; using std::endl; // 窗口类 class Window{ public: Window(const string &win_title); void display() const; void close(); void add_button(const string &label); private: string title; vector<Button> buttons; }; Window::Window(const string &win_title): title{win_title} { buttons.push_back(Button("close")); } inline void Window::display() const { string s(40, '*'); cout << s << endl; cout << "window title: " << title << endl; cout << "It has " << buttons.size() << " buttons: " << endl; for(const auto &i: buttons) cout << i.get_label() << " button" << endl; cout << s << endl; } void Window::close() { cout << "close window '" << title << "'" << endl; buttons.at(0).click(); } void Window::add_button(const string &label) {buttons.push_back(Button(label)); } task1.cpp #include "window.hpp" #include <iostream> using std::cout; using std::cin; void test() { Window w1("new window"); w1.add_button("maximize"); w1.display(); w1.close(); } int main() { cout << "用组合类模拟简单GUI:\n"; test(); }View Code
问题1:2个类。使用了vector,iostream,string类。window和button之间存在组合关系。
问题2:不适合。const对象不可修改,inline函数是用于提高效率,代码编写时未用到说明此处不适用或者用了不起作用,尤其是const修饰时可能会导致构造函数失去作用。
问题3:输出40个“*”来分割界面。
任务二
task2.cpp
#include <iostream> #include <vector> using namespace std; void output1(const vector<int> &v) { for(auto &i: v) cout << i << ", "; cout << "\b\b \n"; } void output2(const vector<vector<int>> v) { for(auto &i: v) { for(auto &j: i) cout << j << ", "; cout << "\b\b \n"; } } void test1() { vector<int> v1(5, 42); const vector<int> v2(v1); v1.at(0) = -999; cout << "v1: "; output1(v1); cout << "v2: "; output1(v2); cout << "v1.at(0) = " << v1.at(0) << endl; cout << "v2.at(0) = " << v2.at(0) << endl; } void test2() { vector<vector<int>> v1{{1, 2, 3}, {4, 5, 6, 7}}; const vector<vector<int>> v2(v1); v1.at(0).push_back(-999); cout << "v1: \n"; output2(v1); cout << "v2: \n"; output2(v2); vector<int> t1 = v1.at(0); cout << t1.at(t1.size()-1) << endl; const vector<int> t2 = v2.at(0); cout << t2.at(t2.size()-1) << endl; } int main() { cout << "测试1:\n"; test1(); cout << "\n测试2:\n"; test2(); }View Code
问题1:用42初始化5个int类型的元素并存入v2。将v1复制给v2。将v1索引为0的元素赋值为-999。
问题2:用两个子向量初始化v1。将v1拷贝给v2。将v1索引为0的元素赋值为-999。
问题3:将v1的第一个元素赋值给t1。输出t1的最后一个元素。将v2的第一个元素赋值给t2。输出t2的最后一个元素。
问题4:深复制。不需要。
任务三
task3.cpp
vectorlnt.hpp #pragma once #include <iostream> #include <cassert> using std::cout; using std::endl; // 动态int数组对象类 class vectorInt{ public: vectorInt(int n); vectorInt(int n, int value); vectorInt(const vectorInt &vi); ~vectorInt(); int& at(int index); const int& at(int index) const; vectorInt& assign(const vectorInt &v); int get_size() const; private: int size; int *ptr; // ptr指向包含size个int的数组 }; vectorInt::vectorInt(int n): size{n}, ptr{new int[size]} { } vectorInt::vectorInt(int n, int value): size{n}, ptr{new int[size]} { for(auto i = 0; i < size; ++i) ptr[i] = value; } vectorInt::vectorInt(const vectorInt &vi): size{vi.size}, ptr{new int[size]} { for(auto i = 0; i < size; ++i) ptr[i] = vi.ptr[i]; } vectorInt::~vectorInt() { delete [] ptr; } const int& vectorInt::at(int index) const { assert(index >= 0 && index < size); return ptr[index]; } int& vectorInt::at(int index) { assert(index >= 0 && index < size); return ptr[index]; } vectorInt& vectorInt::assign(const vectorInt &v) { delete[] ptr; // 释放对象中ptr原来指向的资源 size = v.size; ptr = new int[size]; for(int i = 0; i < size; ++i) ptr[i] = v.ptr[i]; return *this; } int vectorInt::get_size() const { return size; } task3.cpp #include "vectorInt.hpp" #include <iostream> using std::cin; using std::cout; void output(const vectorInt &vi) { for(auto i = 0; i < vi.get_size(); ++i) cout << vi.at(i) << ", "; cout << "\b\b \n"; } void test1() { int n; cout << "Enter n: "; cin >> n; vectorInt x1(n); for(auto i = 0; i < n; ++i) x1.at(i) = i*i; cout << "x1: "; output(x1); vectorInt x2(n, 42); vectorInt x3(x2); x2.at(0) = -999; cout << "x2: "; output(x2); cout << "x3: "; output(x3); } void test2() { const vectorInt x(5, 42); vectorInt y(10, 0); cout << "y: "; output(y); y.assign(x); cout << "y: "; output(y); cout << "x.at(0) = " << x.at(0) << endl; cout << "y.at(0) = " << y.at(0) << endl; } int main() { cout << "测试1: \n"; test1(); cout << "\n测试2: \n"; test2(); }View Code
问题1:深复制。
问题2:有。可能会导致函数出错。
问题3:不可以。可能会导致函数出错。
任务四
task4.cpp
matrix.hpp: #pragma once #include <iostream> #include <cassert> using std::cout; using std::endl; // 类Matrix的声明 class Matrix { public: Matrix(int n, int m); Matrix(int n); Matrix(const Matrix& x); ~Matrix(); void set(const double* pvalue); void clear(); const double& at(int i, int j) const; double& at(int i, int j); int get_lines() const; int get_cols() const; void display() const; private: int lines; int cols; double* ptr; }; int value; Matrix::Matrix(int n, int m) { lines = n; cols = m; ptr = new double[n * m]; } Matrix::Matrix(int n) { lines = n; cols = n; ptr = new double[n * n]; } Matrix::Matrix(const Matrix& x) { ptr = new double[x.lines * x.cols]; for (int i = 0; i < x.lines * x.cols; i++) { ptr[i] = x.ptr[i]; } } Matrix::~Matrix() { delete[] ptr; } void Matrix::set(const double* pvalue) { for (int i = 0; i < lines * cols; i++) ptr[i] = pvalue[i]; } void Matrix::clear() { for (int i = 0; i < lines * cols; i++) ptr[i] = 0; } const double& Matrix::at(int i, int j) const { assert(i >= 0 && i < lines && j >= 0 && j < cols); return ptr[i * cols + j]; } double& Matrix::at(int i, int j) { assert(i >= 0 && i < lines && j >= 0 && j < cols); return ptr[i * cols + j]; } int Matrix::get_lines() const { return lines; } int Matrix::get_cols() const { return cols; } void Matrix::display() const { for (int i = 0; i < lines; i++) { for (int j = 0; j < cols; j++) { cout << at(i, j) << " "; } cout << endl; } } task4.cpp: #include "matrix.hpp" #include <iostream> #include <cassert> using std::cin; using std::cout; using std::endl; const int N = 1000; void output(const Matrix& m, int index) { assert(index >= 0 && index < m.get_lines()); for (auto j = 0; j < m.get_cols(); ++j) cout << m.at(index, j) << ", "; cout << "\b\b \n"; } void test1() { double x[1000] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 }; int n, m; cout << "Enter n and m: "; cin >> n >> m; Matrix m1(n, m); m1.set(x); Matrix m2(m, n); m2.set(x); Matrix m3(2); m3.set(x); cout << "矩阵对象m1: \n"; m1.display(); cout << endl; cout << "矩阵对象m2: \n"; m2.display(); cout << endl; cout << "矩阵对象m3: \n"; m3.display(); cout << endl; } void test2() { Matrix m1(2, 3); m1.clear(); const Matrix m2(m1); m1.at(0, 0) = -999; cout << "m1.at(0, 0) = " << m1.at(0, 0) << endl; cout << "m2.at(0, 0) = " << m2.at(0, 0) << endl; cout << "矩阵对象m1第0行: "; output(m1, 0); cout << "矩阵对象m2第0行: "; output(m2, 0); } int main() { cout << "测试1: \n"; test1(); cout << "测试2: \n"; test2(); }View Code
任务五
task5.cpp
user.hpp: #pragma once #include<vector> #include<iostream> #include<string> using namespace std; class User { public: User(string n); User(string n, string p, string e); void set_email(); void change_password(); void display(); private: string name, password, email; }; User::User(string n) { User::name = n; User::password = "123456"; User::email = ""; } User::User(string n, string p, string e) { User::name = n; User::password = p; User::email = e; } void User::set_email() { string e; cout << "Enter email address:"; cin >> e; int s = 0; while (s != 1) { for (int i = 0; i < e.size(); i++) { if (e[i] == '@') { s = 1; break; } } if (s == 1) { break; } else { cout << "illegal email.Please re-enter email:"; cin >> e; } } cout << "email is set successfully..." << endl; User::email = e; } void User::display() { string pas = User::password; string pass(pas.size(), '*'); cout << "name:" << User::name << "\n" << "pass:" << pass << "\n" << "email:" << User::email << endl; } void User::change_password() { string pas = User::password; string p, np; cout << "Enter old password:"; int t = 1; for (int i = 0; i < 4; i++) { cin >> p; if (p == pas && t <3) { cout << "Enter new password:"; cin >> np; User::password = np; cout << "new password is set successfully..." << endl; break; } else if (p != pas && t <3) { cout << "password input error.Please re-enter again:"; t += 1; continue; } else { cout << "password input error.Please try after a while." << endl; break; } } } task5.cpp: #include "user.hpp" #include <iostream> #include <vector> #include <string> using std::cin; using std::cout; using std::endl; using std::vector; using std::string; void test() { vector<User> user_lst; User u1("Alice", "2024113", "[email protected]"); user_lst.push_back(u1); cout << endl; User u2("Bob"); u2.set_email(); u2.change_password(); user_lst.push_back(u2); cout << endl; User u3("Hellen"); u3.set_email(); u3.change_password(); user_lst.push_back(u3); cout << endl; cout << "There are " << user_lst.size() << " users. they are: " << endl; for (auto& i : user_lst) { i.display(); cout << endl; } } int main() { test(); }View Code
任务六
task6.cpp
account.h: #pragma once #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; }; date.h: #pragma once class Date { private: int year; int month; int day; int totalDays; public: Date(int year, int month, int days); int getYear()const{return year;} int getDay()const { return day; } int getMonth()const { return month; } 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; } }; account.cpp: #include"account.h" #include<iostream> #include<cmath> 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 enougth 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; } date.cpp: #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(); } 6_25.cpp: #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; }View Code
标签:std,const,cout,对象,void,编程,int,实验,string From: https://www.cnblogs.com/Altairsss/p/18525623