类的组合、继承、模板类、标准库
任务2
GradeCalc.hpp
1 #include <iostream> 2 #include <vector> 3 #include <string> 4 #include <algorithm> 5 #include <numeric> 6 #include <iomanip> 7 8 using std::vector; 9 using std::string; 10 using std::cin; 11 using std::cout; 12 using std::endl; 13 14 class GradeCalc: public vector<int> { 15 public: 16 GradeCalc(const string &cname, int size); 17 void input(); // 录入成绩 18 void output() const; // 输出成绩 19 void sort(bool ascending = false); // 排序 (默认降序) 20 int min() const; // 返回最低分 21 int max() const; // 返回最高分 22 float average() const; // 返回平均分 23 void info(); // 输出课程成绩信息 24 25 private: 26 void compute(); // 成绩统计 27 28 private: 29 string course_name; // 课程名 30 int n; // 课程人数 31 vector<int> counts = vector<int>(5, 0); // 保存各分数段人数（[0, 60), [60, 70), [70, 80), [80, 90), [90, 100] 32 vector<double> rates = vector<double>(5, 0); // 保存各分数段比例 33 }; 34 35 GradeCalc::GradeCalc(const string &cname, int size): course_name{cname}, n{size} {} 36 37 void GradeCalc::input() { 38 int grade; 39 40 for(int i = 0; i < n; ++i) { 41 cin >> grade; 42 this->push_back(grade); 43 } 44 } 45 46 void GradeCalc::output() const { 47 for(auto ptr = this->begin(); ptr != this->end(); ++ptr) 48 cout << *ptr << " "; 49 cout << endl; 50 } 51 52 void GradeCalc::sort(bool ascending) { 53 if(ascending) 54 std::sort(this->begin(), this->end()); 55 else 56 std::sort(this->begin(), this->end(), std::greater<int>()); 57 } 58 59 int GradeCalc::min() const { 60 return *std::min_element(this->begin(), this->end()); 61 } 62 63 int GradeCalc::max() const { 64 return *std::max_element(this->begin(), this->end()); 65 } 66 67 float GradeCalc::average() const { 68 return std::accumulate(this->begin(), this->end(), 0) * 1.0 / n; 69 } 70 71 void GradeCalc::compute() { 72 for(int grade: *this) { 73 if(grade < 60) 74 counts.at(0)++; 75 else if(grade >= 60 && grade < 70) 76 counts.at(1)++; 77 else if(grade >= 70 && grade < 80) 78 counts.at(2)++; 79 else if(grade >= 80 && grade < 90) 80 counts.at(3)++; 81 else if(grade >= 90) 82 counts.at(4)++; 83 } 84 85 for(int i = 0; i < rates.size(); ++i) 86 rates.at(i) = counts.at(i) * 1.0 / n; 87 } 88 89 void GradeCalc::info() { 90 cout << "课程名称:\t" << course_name << endl; 91 cout << "排序后成绩: \t"; 92 sort(); output(); 93 cout << "最高分:\t" << max() << endl; 94 cout << "最低分:\t" << min() << endl; 95 cout << "平均分:\t" << std::fixed << std::setprecision(2) << average() << endl; 96 97 compute(); // 统计各分数段人数、比例 98 99 vector<string> tmp{"[0, 60) ", "[60, 70)", "[70, 80)","[80, 90)", "[90, 100]"}; 100 for(int i = tmp.size()-1; i >= 0; --i) 101 cout << tmp[i] << "\t: " << counts[i] << "人\t" 102 << std::fixed << std::setprecision(2) << rates[i]*100 << "%" << endl; 103 }
demo2.cpp
1 #include "GradeCalc.hpp" 2 #include <iomanip> 3 4 void test() { 5 int n; 6 cout << "输入班级人数: "; 7 cin >> n; 8 9 GradeCalc c1("OOP", n); 10 11 cout << "录入成绩: " << endl;; 12 c1.input(); 13 cout << "输出成绩: " << endl; 14 c1.output(); 15 16 cout << string(20, '*') + "课程成绩信息" + string(20, '*') << endl; 17 c1.info(); 18 } 19 20 int main() { 21 test(); 22 }
运行结果
问题1：
成绩存储在vector<int>类数组中；sort,min,max,average,output是通过vector<int>中的begin(),end()接口访问每个成绩的；input是通过vector<int>中的push_back()接口实现数据存入对象的。
问题2：
功能：分母为人数，用来计算总分数的平均值；去掉*1.0代码，运行结果如下：
结果影响了平均分精度；*1.0是为了将整型转化为浮点型以提高结果精度。
问题3：
1. 课程人数的管理
- 当前问题: 类中使用
n为课程人数，但这个参数的意义并未得到充分利用，比如在计算平均分时是否应该考虑课程人数的变化。 - 改进建议: 使用
vector<int> scores动态存储成绩，避免定义单独的n，因为总人数应从scores的大小中推导出来。
2. 输入验证
- 当前问题:
input方法未对输入的成绩进行验证。用户可能输入负值或超过 100 的成绩。 - 改进建议: 在录入成绩时，加入输入验证逻辑，确保录入的成绩在合理范围内。
3. 统计和报告的灵活性
- 当前问题:
info方法可能会输出固定的信息，未考虑灵活的报告需求。 - 改进建议: 增加参数设置，使得输出信息可以自定义，例如输出成绩分布、分数段详情等。
4. 增加功能
- 增添成绩的删除或修改功能。
- 增加统计分数段（例如通过
counts和rates输出更详细的分数分析）。
任务3
GradeCalc.hpp
1 #include <iostream> 2 #include <vector> 3 #include <string> 4 #include <algorithm> 5 #include <numeric> 6 #include <iomanip> 7 8 using std::vector; 9 using std::string; 10 using std::cin; 11 using std::cout; 12 using std::endl; 13 14 class GradeCalc { 15 public: 16 GradeCalc(const string &cname, int size); 17 void input(); // 录入成绩 18 void output() const; // 输出成绩 19 void sort(bool ascending = false); // 排序 (默认降序) 20 int min() const; // 返回最低分 21 int max() const; // 返回最高分 22 float average() const; // 返回平均分 23 void info(); // 输出课程成绩信息 24 25 private: 26 void compute(); // 成绩统计 27 28 private: 29 string course_name; // 课程名 30 int n; // 课程人数 31 vector<int> grades; // 课程成绩 32 vector<int> counts = vector<int>(5, 0); // 保存各分数段人数（[0, 60), [60, 70), [70, 80), [80, 90), [90, 100] 33 vector<double> rates = vector<double>(5, 0); // 保存各分数段比例 34 }; 35 36 GradeCalc::GradeCalc(const string &cname, int size): course_name{cname}, n{size} {} 37 38 void GradeCalc::input() { 39 int grade; 40 41 for(int i = 0; i < n; ++i) { 42 cin >> grade; 43 grades.push_back(grade); 44 } 45 } 46 47 void GradeCalc::output() const { 48 for(int grade: grades) 49 cout << grade << " "; 50 cout << endl; 51 } 52 53 void GradeCalc::sort(bool ascending) { 54 if(ascending) 55 std::sort(grades.begin(), grades.end()); 56 else 57 std::sort(grades.begin(), grades.end(), std::greater<int>()); 58 59 } 60 61 int GradeCalc::min() const { 62 return *std::min_element(grades.begin(), grades.end()); 63 } 64 65 int GradeCalc::max() const { 66 return *std::max_element(grades.begin(), grades.end()); 67 } 68 69 float GradeCalc::average() const { 70 return std::accumulate(grades.begin(), grades.end(), 0) * 1.0 / n; 71 } 72 73 void GradeCalc::compute() { 74 for(int grade: grades) { 75 if(grade < 60) 76 counts.at(0)++; 77 else if(grade >= 60 && grade < 70) 78 counts.at(1)++; 79 else if(grade >= 70 && grade < 80) 80 counts.at(2)++; 81 else if(grade >= 80 && grade < 90) 82 counts.at(3)++; 83 else if(grade >= 90) 84 counts.at(4)++; 85 } 86 87 for(int i = 0; i < rates.size(); ++i) 88 rates.at(i) = counts.at(i) *1.0 / n; 89 } 90 91 void GradeCalc::info() { 92 cout << "课程名称:\t" << course_name << endl; 93 cout << "排序后成绩: \t"; 94 sort(); output(); 95 cout << "最高分:\t" << max() << endl; 96 cout << "最低分:\t" << min() << endl; 97 cout << "平均分:\t" << std::fixed << std::setprecision(2) << average() << endl; 98 99 compute(); // 统计各分数段人数、比例 100 101 vector<string> tmp{"[0, 60) ", "[60, 70)", "[70, 80)","[80, 90)", "[90, 100]"}; 102 for(int i = tmp.size()-1; i >= 0; --i) 103 cout << tmp[i] << "\t: " << counts[i] << "人\t" 104 << std::fixed << std::setprecision(2) << rates[i]*100 << "%" << endl; 105 }
demo3.cpp
1 #include "GradeCalc.hpp" 2 #include <iomanip> 3 4 void test() { 5 int n; 6 cout << "输入班级人数: "; 7 cin >> n; 8 9 GradeCalc c1("OOP", n); 10 11 cout << "录入成绩: " << endl;; 12 c1.input(); 13 cout << "输出成绩: " << endl; 14 c1.output(); 15 16 cout << string(20, '*') + "课程成绩信息" + string(20, '*') << endl; 17 c1.info(); 18 } 19 20 int main() { 21 test(); 22 }
测试结果
问题1：成绩存储在类中私有vector<int>型成员 grades中；sort,min,max,average,output是通过grades.begin(), grades.end()接口访问成绩的。细节差别：本实验代码在类的似有成员中新增
vector<int> grades ，vector<int> counts ，vector<double> rates 对象，在成员方法中直接用grades.来调用继承来的方法。
问题2：面向对象编程可以在不影响主体代码逻辑和接口的情况下修改类的设计接口和内部细节，使得对代码的修改优化更为便利和可控。
任务4
task4_1.cpp
1 #include <iostream> 2 #include <string> 3 #include <limits> 4 5 using namespace std; 6 7 void test1() { 8 string s1, s2; 9 cin >> s1 >> s2; // cin: 从输入流读取字符串, 碰到空白符(空格/回车/Tab)即结束 10 cout << "s1: " << s1 << endl; 11 cout << "s2: " << s2 << endl; 12 } 13 14 void test2() { 15 string s1, s2; 16 getline(cin, s1); // getline(): 从输入流中提取字符串，直到遇到换行符 17 getline(cin, s2); 18 cout << "s1: " << s1 << endl; 19 cout << "s2: " << s2 << endl; 20 } 21 22 void test3() { 23 string s1, s2; 24 getline(cin, s1, ' '); //从输入流中提取字符串，直到遇到指定分隔符 25 getline(cin, s2); 26 cout << "s1: " << s1 << endl; 27 cout << "s2: " << s2 << endl; 28 } 29 30 int main() { 31 cout << "测试1: 使用标准输入流对象cin输入字符串" << endl; 32 test1(); 33 cout << endl; 34 35 cin.ignore(numeric_limits<streamsize>::max(), '\n'); 36 37 cout << "测试2: 使用函数getline()输入字符串" << endl; 38 test2(); 39 cout << endl; 40 41 cout << "测试3: 使用函数getline()输入字符串, 指定字符串分隔符" << endl; 42 test3(); 43 }
运行结果
问题1：去掉后运行结果
用途：清空输入缓存区，防止错误输入
task4_2.cpp
1 #include <iostream> 2 #include <string> 3 #include <vector> 4 #include <limits> 5 6 using namespace std; 7 8 void output(const vector<string> &v) { 9 for(auto &s: v) 10 cout << s << endl; 11 } 12 13 void test() { 14 int n; 15 while(cout << "Enter n: ", cin >> n) { 16 vector<string> v1; 17 18 for(int i = 0; i < n; ++i) { 19 string s; 20 cin >> s; 21 v1.push_back(s); 22 } 23 24 cout << "output v1: " << endl; 25 output(v1); 26 cout << endl; 27 } 28 } 29 30 int main() { 31 cout << "测试: 使用cin多组输入字符串" << endl; 32 test(); 33 }
运行结果
task4_3.cpp
1 #include <iostream> 2 #include <string> 3 #include <vector> 4 #include <limits> 5 6 using namespace std; 7 8 void output(const vector<string> &v) { 9 for(auto &s: v) 10 cout << s << endl; 11 } 12 13 void test() { 14 int n; 15 while(cout << "Enter n: ", cin >> n) { 16 cin.ignore(numeric_limits<streamsize>::max(), '\n'); 17 18 vector<string> v2; 19 20 for(int i = 0; i < n; ++i) { 21 string s; 22 getline(cin, s); 23 v2.push_back(s); 24 } 25 cout << "output v2: " << endl; 26 output(v2); 27 cout << endl; 28 } 29 } 30 31 int main() { 32 cout << "测试: 使用函数getline()多组输入字符串" << endl; 33 test(); 34 }
运行结果
问题2：去掉后运行结果
用途：清空输入缓存区， 防止换行符被当作字符读入导致错误
任务5
task5.cpp
1 #include "grm.hpp" 2 #include <iostream> 3 4 using std::cout; 5 using std::endl; 6 7 void test1() { 8 GameResourceManager<float> HP_manager(99.99); 9 cout << "当前生命值: " << HP_manager.get() << endl; 10 HP_manager.update(9.99); 11 cout << "增加9.99生命值后, 当前生命值: " << HP_manager.get() << endl; 12 HP_manager.update(-999.99); 13 cout <<"减少999.99生命值后, 当前生命值: " << HP_manager.get() << endl; 14 } 15 16 void test2() { 17 GameResourceManager<int> Gold_manager(100); 18 cout << "当前金币数量: " << Gold_manager.get() << endl; 19 Gold_manager.update(50); 20 cout << "增加50个金币后, 当前金币数量: " << Gold_manager.get() << endl; 21 Gold_manager.update(-99); 22 cout <<"减少99个金币后, 当前金币数量: " << Gold_manager.get() << endl; 23 } 24 25 26 int main() { 27 cout << "测试1: 用float类型对类模板GameResourceManager实例化" << endl; 28 test1(); 29 cout << endl; 30 31 cout << "测试2: 用int类型对类模板GameResourceManager实例化" << endl; 32 test2(); 33 }
grm.hpp
1 #include<iostream> 2 3 4 using std::cout; 5 using std::endl; 6 7 template<typename T> 8 class GameResourceManager{ 9 public: 10 GameResourceManager(T x0); 11 T get(); 12 void update(T y0); 13 private: 14 T x; 15 }; 16 17 template<typename T> 18 GameResourceManager<T>::GameResourceManager(T x0):x{x0} { 19 } 20 21 template<typename T> 22 T GameResourceManager<T>::get() { 23 return x; 24 } 25 26 template<typename T> 27 void GameResourceManager<T>::update(T y0) { 28 x+=y0; 29 if(x<0) 30 x=0; 31 }
运行结果
任务6
info.hpp
1 #include<iostream> 2 #include<string> 3 #include <iomanip> 4 5 using std::cout; 6 using std::endl; 7 using std::string; 8 using std::setw; 9 10 class Info{ 11 public: 12 Info(string nickname0,string contact0,string city0,int n0); 13 void display(); 14 private: 15 string nickname; 16 string contact; 17 string city; 18 int n; 19 }; 20 21 Info::Info(string nickname0,string contact0,string city0,int n0):nickname(nickname0),contact(contact0),city(city0),n(n0) { 22 } 23 24 void Info::display() 25 { 26 27 cout<<"-------------------------------\n"; 28 cout<<setw(10)<<"昵称"<<nickname<<endl; 29 cout<<setw(10)<<"联系方式"<<contact<<endl; 30 cout<<setw(10)<<"所在城市"<<city<<endl; 31 cout<<setw(10)<<"预定人数"<<n<<endl; 32 }
task5.cpp
1 #include<iostream> 2 #include<string> 3 #include<vector> 4 #include <iomanip> 5 #include"info.hpp" 6 7 using namespace std; 8 using std::setw; 9 10 int main() 11 { 12 const int capacity=100; 13 vector<Info> audience_lst; 14 char choice; 15 string nickname,contact,city; 16 int n; 17 cout<<"录入用户预约信息：\n"<<endl; 18 cout<<"昵称"<<setw(30)<<"联系方式（邮箱/手机号）"<<setw(20)<<"所在城市"<<setw(20)<<"预定参加人数"<<endl; 19 int i=0,sum=0; 20 while((cin>>nickname>>contact>>city>>n)) 21 { 22 //cin>>nickname>>contact>>city>>n; 23 audience_lst.push_back(Info(nickname,contact,city,n)); 24 sum+=n; 25 i++; 26 if(sum>capacity) 27 { 28 sum-=n; 29 cout<<"对不起，只剩"<<capacity-sum<<"个位置。\n"; 30 cout<<"1.输入u,更新（update）预定信息\n"; 31 cout<<"2.输入q,退出预定\n"; 32 cout<<"你的选择："; 33 cin>>choice; 34 if(choice=='u') 35 { 36 cout<<"请重新输入预定信息：\n"; 37 i--; 38 continue; 39 } 40 else 41 { 42 break; 43 } 44 } 45 46 } 47 48 cout<<"截至目前，一共有"<<sum<<"位听众预约。预约听众信息如下：\n"; 49 for(int j=0;j<i;j++) 50 { 51 audience_lst[j].display(); 52 } 53 }
运行结果
任务7
7_10.cpp
1 #include"account.h" 2 #include<iostream> 3 4 using namespace std; 5 6 int main() { 7 Date date(2008, 11, 1); 8 SavingsAccount sa1(date, "S3755217", 0.015); 9 SavingsAccount sa2(date, "02342342", 0.015); 10 CreditAccount ca(date, "C5392394", 10000, 0.0005, 50); 11 12 sa1.deposit(Date(2008, 11, 5), 5000, "salary"); 13 ca.withdraw(Date(2008, 11, 15), 2000, "buy a cell"); 14 sa2.deposit(Date(2008, 11, 25), 10000, "sell stock 0323"); 15 16 ca.settle(Date(2008, 12, 1)); 17 18 ca.deposit(Date(2008, 12, 1), 2016, "repay the credit"); 19 sa1.deposit(Date(2008, 12, 5), 5500, "salary"); 20 21 sa1.settle(Date(2009, 1, 1)); 22 sa2.settle(Date(2009, 1, 1)); 23 ca.settle(Date(2009, 1, 1)); 24 25 cout << endl; 26 sa1.show(); cout << endl; 27 sa2.show(); cout << endl; 28 ca.show(); cout << endl; 29 cout << "Total:" << Account::getTotal() << endl; 30 return 0; 31 }
account.cpp
1 #include"account.h" 2 #include<cmath> 3 #include<iostream> 4 using namespace std; 5 double Account::total = 0; 6 7 Account::Account(const Date& date, const string& id) :id{ id }, balance{ 0 } { 8 date.show(); cout << "\t#" << id << "created" << endl; 9 } 10 11 12 void Account::record(const Date& date, double amount, const string& desc) { 13 amount = floor(amount * 100 + 0.5) / 100; 14 balance += amount; 15 total += amount; 16 date.show(); 17 cout << "\t#" << id << "\t" << amount << "\t" << balance << "\t" << desc << endl; 18 } 19 20 void Account::show()const { cout << id << "\tBalance:" << balance; } 21 void Account::error(const string& msg)const { 22 cout << "Error(#" << id << "):" << msg << endl; 23 } 24 25 SavingsAccount::SavingsAccount(const Date& date, const string& id, double rate) :Account(date, id), rate(rate), acc(date, 0) {} 26 27 void SavingsAccount::deposit(const Date& date, double amount, const string& desc) { 28 record(date, amount, desc); 29 acc.change(date, getBalance()); 30 } 31 32 void SavingsAccount::withdraw(const Date& date, double amount, const string& desc) { 33 if (amount > getBalance()) { 34 error("not enough money"); 35 } 36 else { 37 record(date, -amount, desc); 38 acc.change(date, getBalance()); 39 } 40 } 41 42 void SavingsAccount::settle(const Date& date) { 43 double interest = acc.getSum(date) * rate / date.distance(Date(date.getYear() - 1, 1, 1)); 44 if (interest != 0)record(date, interest, "interest"); 45 acc.reset(date, getBalance()); 46 } 47 48 CreditAccount::CreditAccount(const Date& date, const string& id, double credit, double rate, double fee) :Account(date, id), credit(credit), rate(rate), fee(fee), acc(date, 0) {} 49 50 void CreditAccount::deposit(const Date& date, double amount, const string& desc) { 51 record(date, amount, desc); 52 acc.change(date, getDebt()); 53 } 54 55 void CreditAccount::withdraw(const Date& date, double amount, const string& desc) { 56 if (amount - getBalance() > credit) { 57 error("not enough credit"); 58 } 59 else { 60 record(date, -amount, desc); 61 acc.change(date, getDebt()); 62 } 63 } 64 65 void CreditAccount::settle(const Date& date) { 66 double interest = acc.getSum(date) * rate; 67 if (interest != 0)record(date, interest, "interest"); 68 if (date.getMonth() == 1) 69 record(date, -fee, "annual fee"); 70 acc.reset(date, getDebt()); 71 } 72 73 void CreditAccount::show()const { 74 Account::show(); 75 cout << "\tAvailable credit:" << getAvailableCredit(); 76 }
account.h
1 #pragma once 2 #ifndef ACCOUNT H 3 #define ACCOUNT H 4 #include"date.h" 5 #include"accumulator.h" 6 #include<string> 7 class Account { 8 private: 9 std::string id; 10 double balance; 11 static double total; 12 protected: 13 Account(const Date& date, const std::string& id); 14 void record(const Date& date, double amount, const std::string& desc); 15 void error(const std::string& msg)const; 16 public: 17 const std::string& getId()const { return id; } 18 double getBalance()const { return balance; } 19 static double getTotal() { return total; } 20 21 void show()const; 22 }; 23 class SavingsAccount :public Account { 24 private: 25 Accumulator acc; 26 double rate; 27 public: 28 SavingsAccount(const Date& date, const std::string& id, double rate); 29 double getRate()const { return rate; } 30 31 void deposit(const Date& date, double amount, const std::string& desc); 32 void withdraw(const Date& date, double amount, const std::string& desc); 33 void settle(const Date& date); 34 }; 35 class CreditAccount :public Account { 36 private: 37 Accumulator acc; 38 double credit; 39 double rate; 40 double fee; 41 double getDebt()const { 42 double balance = getBalance(); 43 return (balance < 0 ? balance : 0); 44 } 45 public: 46 CreditAccount(const Date& date, const std::string& id, double credit, double rate, double fee); 47 double getCredit()const { return credit; } 48 double getRate()const { return rate; } 49 double getAvailableCredit()const { 50 if (getBalance() < 0) 51 return credit + getBalance(); 52 else 53 return credit; 54 } 55 void deposit(const Date& date, double amount, const std::string& desc); 56 void withdraw(const Date& date, double amount, const std::string& desc); 57 void settle(const Date& date); 58 void show()const; 59 }; 60 #endif//ACCOUNT H
accumulator.h
1 #pragma once 2 #ifndef ACCUMULATOR H 3 #define ACCUMULATOR H 4 #include"date.h" 5 class Accumulator { 6 private: 7 Date lastDate; 8 double value; 9 double sum; 10 public: 11 Accumulator(const Date& date, double value) :lastDate(date), value(value), sum{ 0 } { 12 } 13 14 double getSum(const Date& date)const { 15 return sum + value * date.distance(lastDate); 16 } 17 18 void change(const Date& date, double value) { 19 sum = getSum(date); 20 lastDate = date; this->value = value; 21 } 22 23 void reset(const Date& date, double value) { 24 lastDate = date; this->value = value; sum = 0; 25 } 26 }; 27 #endif//ACCUMULATOR H
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 20 int Date::getMaxDay() const { 21 if(isLeapYear()&&month==2) 22 return 29; 23 else 24 return DAYS_BEFORE_MONTH[month]-DAYS_BEFORE_MONTH[month-1]; 25 } 26 27 void Date::show() const { 28 cout<<getYear()<<"-"<<getMonth()<<"-"<<getDay(); 29 }
date.h
1 #ifndef __DATE_H__ 2 #define __DATE_H__ 3 class Date{ 4 private: 5 int year; 6 int month; 7 int day; 8 int totalDays; 9 public: 10 Date(int year,int month,int day); 11 int getYear() const {return year;} 12 int getMonth() const {return month;} 13 int getDay() const {return day;} 14 int getMaxDay() const; 15 bool isLeapYear() const { 16 return year%4==0 && year%100 !=0 ||year%400==0; 17 } 18 void show() const; 19 20 int distance(const Date& date) const { 21 return totalDays-date.totalDays; 22 } 23 }; 24 #endif //__DATE_H__
运行结果
使用了继承方法，减少代码的重复，实现功能的扩展，更易于程序的后期修改和维护。
