这个程序是一个银行账户管理的程序，是用C++来实现程序功能的，该程序包含六个文件，其中有date.h头文件
是日期类的头文件，date.cpp是日期类的实现文件，accumulator.h是按日将数值累加的accumulator类的头文件，
account.h是各个储蓄账户类定义的头文件，account.cpp是各个储蓄账户类的实现文件，还有就是主函数文件。该
程序包含了增加账户功能、存款功能、取款功能、查询账户信息功能、改变日期功能、进入下个月的处理功能，最
后是退出程序。下面是各个程序文件：
1.date.h日期类的头文件
#ifndef _DATE_H #define _DATE_H #include <iostream> using namespace std; class Date { public:Date(int year = 1,int month = 1,int day = 1);int getYear()const{return year;}int getMonth()const{return month;}int getDay()const{return day;}int getMaxDay()const; //获得当月有多少天bool isLeapYear() const //判断当年是否为闰年 {return year % 4 == 0 && year % 100 != 0 && year % 400 == 0;}void show()const; //输出当前日期int operator-(const Date &date)const //计算两个日期之间差多少天 {return totalDays - date.totalDays;}bool operator<(const Date &date)const //判断两个日期的前后顺序 {return totalDays < date.totalDays;} private:int year;int month;int day;int totalDays; //该日期是从公元元年1月1日开始的第几天 }; istream& operator >> (istream &in, Date &date); ostream& operator << (ostream &out, const Date &date);#endif
2.date.cpp日期类实现的文件
#include <iostream> #include <stdexcept> #include "date.h" using namespace std;namespace //namespace使下面的定义只在当前文件中有效 {//存储平年中的某个月1日之前有多少天，为便于getMaxDay函数的实现，该数组多出一项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())throw runtime_error("Invalid date");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;elsereturn DAYS_BEFORE_MONTH[month] - DAYS_BEFORE_MONTH[month - 1]; } void Date::show()const {cout << getYear() << "-" << getMonth() << "-" << getDay(); } istream& operator >> (istream &in, Date &date) {int year, month, day;char c1, c2;in >> year >> c1 >> month >> c2 >> day;if (c1 != '-' || c2 != '-')throw runtime_error("Bad time format");date = Date(year, month, day);return in; } ostream& operator<<(ostream &out, const Date &date) {out << date.getYear() << "-" << date.getMonth() << "-" << date.getDay();return out; }
3.accumulator.h按日将数值累加的头文件
#ifndef _ACCUMULATOR_H #define _ACCUMULATOR_H #include "date.h" class Accumulator //将某个数值按日累加 { public://date为开始累加的日期，value为初始值Accumulator(const Date &date, double value):lastDate(date),value(value),sum(0){}double getSum(const Date &date)const{return sum + value*(date - lastDate);}//在date将数值变更为valuevoid change(const Date &date, double value){sum = getSum(date);lastDate = date;this->value = value;}//初始化，将日期变为date,数值变为value,累加器清零void reset(const Date &date, double value){lastDate = date;this->value = value;sum = 0;} private:Date lastDate; //上次变更数值的时期double value; //数值的当前值double sum; //数值按日累加之和 };#endif
4.account.h各个储蓄账户类定义的头文件
#ifndef _ACCOUNT_H #define _ACCOUNT_H #include "date.h" #include "accumulator.h" #include <iostream> #include <string> #include <map> #include <istream> #include <stdexcept> using namespace std;class Account; class AccountRecord //账目记录 { public:AccountRecord(const Date &date, const Account* account, double amount, double balance, const string &desc);void show()const; //输出当前记录 private:Date date; //日期const Account* account; //账户double amount; //金额double balance; //余额string desc; //描述 };typedef multimap<Date, AccountRecord> RecordMap; //账户类 class Account { public:const string& getId()const{return id;}double getBalance()const{return balance;}static double getTotal(){return total;}//存入现金，date为日期，amount为金额，desc为款项说明virtual void deposit(const Date &date, double amount, const string &desc) = 0;//取出现金，date为日期，amount为金额，desc为款项说明virtual void withdraw(const Date &date, double amount, const string &desc) = 0;//结算，每月结算一次，date为结算日期virtual void settle(const Date &date) = 0;//显示账户信息virtual void show(ostream &out)const;//查询指定时间内的账目记录static void query(const Date &begin, const Date &end); protected://供派生类调用的构造函数Account(const Date &date, const string &id);//记录一笔账，date为日期，amount为金额，desc为说明void record(const Date &date, double amount, const string &desc);//报告错误信息void error(const string &msg)const; private:string id; //账户double balance; //余额static double total; //所有账户的总金额static RecordMap recordMap; //账目记录 }; inline ostream& operator<<(ostream &out, const Account &account) {account.show(out);return out; }class SavingAccount :public Account //储蓄账户类 { public:SavingAccount(const Date &date, const string &id, double rate);double getRate()const{return rate;}//存入现金void deposit(const Date &date, double amount, const string &desc);//取出现金void withdraw(const Date &date, double amount, const string &desc);//结算利息，每年1月1日调用一次该函数void settle(const Date &date); private:Accumulator acc; //辅助计算利息的累加器double rate; //存款的年利率 };class CreditAccount :public Account //信用账户类 { public:CreditAccount(const Date &date, const string &id, double credit, double rate, double fee);double getCredit()const{return credit;}double getRate()const{return rate;}double getFee()const{return fee;}double getAvailableCredit()const //获得可用信用额度 {if (getBalance() < 0)return credit + getBalance();elsereturn credit;}//存入现金void deposit(const Date &date, double amount, const string &desc);//取出现金void withdraw(const Date &date, double amount, const string &desc);//结算利息和年费，每月1日调用一次该函数void settle(const Date &date);virtual void show(ostream &out)const; private:Accumulator acc; //辅助计算利息的累加器double credit; //信用额度double rate; //欠款的日利率double fee; //信用卡年费double getDebt() const //获得欠款额 {double balance = getBalance();return (balance < 0 ? balance : 0);} };class AccountException :public runtime_error { public:AccountException(const Account* account, const string &msg) :runtime_error(msg), account(account){}const Account* getAccount()const{return account;} private:const Account* account; };#endif
5.account.cpp各个储蓄账户类的实现文件
#include <iostream> #include <cmath> #include <utility> #include "account.h" using namespace std; using namespace std::rel_ops;//AccountRecord类的实现 AccountRecord::AccountRecord(const Date &date,const Account* account,double amount,double balance,const string &desc):\ date(date), account(account), amount(amount), balance(balance), desc(desc) { } void AccountRecord::show()const {cout << date << "\t#" << account->getId() << "\t" << amount << "\t" << balance << "\t" << desc << endl; }//Account类的实现 double Account::total = 0; RecordMap Account::recordMap; Account::Account(const Date &date, const string &id):id(id),balance(0) {cout << date << "\t#" << id << " created" << endl; } void Account::record(const Date &date, double amount, const string &desc) {amount = floor(amount * 100 + 0.5) / 100; //保留小数点后两位balance += amount;total += amount;date.show();cout << "\t#" << id << "\t" << amount << "\t" << balance << "\t" << desc << endl; } void Account::show(ostream &out)const {out << id << "\tBalance: " << balance; } void Account::error(const string &msg)const {throw AccountException(this, msg); } void Account::query(const Date &begin, const Date &end) {if (begin <= end){RecordMap::iterator iter1 = recordMap.lower_bound(begin);RecordMap::iterator iter2 = recordMap.upper_bound(end);for (RecordMap::iterator iter = iter1;iter != iter2;++iter)iter->second.show();} }//CreditAccount类的实现 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) { } void CreditAccount::deposit(const Date &date, double amount, const string &desc) {record(date, amount, desc);acc.change(date, getDebt()); } void CreditAccount::withdraw(const Date &date, double amount, const string &desc) {if (amount - getBalance() > credit){error("not enough credit");}else{record(date, -amount, desc);acc.change(date, getDebt());} } void CreditAccount::settle(const Date &date) {double interest = acc.getSum(date)*rate;if (interest != 0)record(date, interest, "interest");if (date.getMonth() == 1)record(date, -fee, "annual fee");acc.reset(date, getDebt()); } void CreditAccount::show(ostream &out)const {Account::show(out);out << "\tAvailable credit: " << getAvailableCredit(); }//SavingAccount类的实现 SavingAccount::SavingAccount(const Date &date, const string &id, double rate) :Account(date, id), rate(rate), acc(date, 0) { } void SavingAccount::deposit(const Date &date, double amount, const string &desc) {record(date, amount, desc);acc.change(date, getBalance()); } void SavingAccount::withdraw(const Date &date, double amount, const string &desc) {if (amount > getBalance()){error("not enough money");}else{record(date, -amount, desc);acc.change(date, getBalance());} } void SavingAccount::settle(const Date &date) {if (date.getMonth() == 1) //每年的1月计算一次利息 {double interest = acc.getSum(date)*rate / (date - Date(date.getYear() - 1, 1, 1));if (interest != 0)record(date, interest, "interest");acc.reset(date, getBalance());} }
6.主函数文件
#include <iostream> #include <string> #include <fstream> #include <sstream> #include <vector> #include <algorithm> #include "account.h" using namespace std;struct deleter {template<class T>void operator()(T *p){delete p;} }; //控制器类，用来存储账户列表和处理命令 class Controller { public:Controller(const Date &date) :date(date), end(false){}~Controller();const Date& getDate()const{return date;}bool isEnd()const{return end;}//执行一条命令，返回该命令是否改变了当前状态(即是否需要保存当前命令)bool runCommand(const string &cmdLine); private:Date date;vector<Account*> accounts; //账户列表bool end; //用户是否输入了退出命令 }; Controller::~Controller() {for_each(accounts.begin(), accounts.end(), deleter()); } bool Controller::runCommand(const string &cmdLine) {istringstream str(cmdLine);char cmd, type;int index, day;double amount, credit, rate, fee;string id, desc;Account* account;Date date1, date2;str >> cmd;switch (cmd){case 'a': //增加账户str >> type >> id;if (type == 's'){str >> rate;account = new SavingAccount(date, id, rate);}else{str >> credit >> rate >> fee;account = new CreditAccount(date, id, credit, rate, fee);}accounts.push_back(account);return true;case 'd': //存入现金str >> index >> amount;getline(str, desc);accounts[index]->deposit(date, amount, desc);return true;case 'w': //取出现金str >> index >> amount;getline(str, desc);accounts[index]->withdraw(date, amount, desc);return true;case 's': //查询各账户信息for (size_t i = 0;i < accounts.size();++i){cout << "[" << i << "]";accounts[i]->show(cout);cout << endl;}return false;case 'c': //改变日期str >> day;if (day < date.getDay())cout << "You cannot specify a previous day";else if (day > date.getMaxDay())cout << "Invalid day";elsedate = Date(date.getYear(), date.getMonth(), day);return true;case 'n': //进入下个月if (date.getMonth() == 12)date = Date(date.getYear() + 1, 1, 1);elsedate = Date(date.getYear(), date.getMonth() + 1, 1);for (vector<Account*>::iterator iter = accounts.begin();iter != accounts.end();++iter)(*iter)->settle(date);return true;case 'q': //查询一段时间内的账目str >> date1 >> date2;Account::query(date1, date2);return false;case 'e': //退出end = true;return false;}cout << "Invalid command: " << cmdLine << endl;return false; } int main() {Date date(2018, 1, 1); //起始日期 Controller controller(date);string cmdLine;const char *FILE_NAME = "commands.txt";ifstream fileIn(FILE_NAME); //以读模式打开文件if (fileIn) //如果正常打开，就执行文件中的每一条命令 {while (getline(fileIn, cmdLine))controller.runCommand(cmdLine);fileIn.close();}ofstream fileOut(FILE_NAME, ios_base::app); //以追加模式打开文件cout << "(a)add account (d)deposit (w)withdraw (s)show (c)change day (n)next month (q)query (e)exit" << endl;while (!controller.isEnd()) //从标准输入读入命令并执行，直到退出 {cout << controller.getDate() << "\tTotal: " << Account::getTotal() << "\tcommand";string cmdLine;getline(cin, cmdLine);if (controller.runCommand(cmdLine))fileOut << cmdLine << endl; //将命令写入文件 }return 0; }
最后运行主函数将程序功能实现，可以进行增加账户功能、存款功能、取款功能、查询账户信息功能、改变日期功
能、进入下个月的处理功能将程序进行操作，最后附上一张我操作这些功能的截图。
