1 //第六章完整代码 
  2 #include<iostream>
  3 #include<cstdlib>
  4 #include<cmath>
  5 using namespace std;    
  6 class Date {
  7 private:
  8     int year;
  9     int month;
 10     int day;
 11     int totalDays;
 12 public:
 13     Date(int year, int month, int day);
 14     int getYear()const { return year; }
 15     int getMonth() const { return month; }
 16     int getDay()const { return day; }
 17     int getMaxDay()const;
 18     bool isLeapYear()const{
 19         return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
 20     }
 21     void show()const;
 22     int distance(const Date &date)const {
 23         return totalDays - date.totalDays;
 24     }
 25 };
 26 namespace 
 27 {
 28     const int DAYS_BEFORE_MONTH[] = {0,31,59,90,120,151,181,212,243,273,304,334,365 };
 29 }
 30 Date::Date(int year, int month, int day) :year(year), month(month), day(day) {
 31     if (day <= 0 || day > getMaxDay()) {
 32         cout << "Invalid date: ";
 33         show();
 34         cout << endl;
 35         exit(1);
 36     }
 37     int years = year - 1;
 38     totalDays = year * 365 + years / 4 - years / 100 + years / 400 + DAYS_BEFORE_MONTH[month - 1] + day;
 39     if (isLeapYear() && month > 2) totalDays++;
 40 }
 41 int Date::getMaxDay()const {
 42     if (isLeapYear() && month == 2)
 43         return 29;
 44     else
 45         return DAYS_BEFORE_MONTH[month] - DAYS_BEFORE_MONTH[month - 1];
 46 }
 47 void Date::show() const {
 48     cout << getYear() <<"-"<< getMonth() <<"-"<< getDay();
 49 }
 50 class SavingsAccount //储蓄账户类
 51 
 52 {
 53 
 54 private:
 55 
 56     std::string id; //账号
 57 
 58     double balance; //余额
 59 
 60     double rate; //存款的年利率
 61 
 62     Date  lastDate; //上次变更余额的日期
 63 
 64     double accumulation; //余额按日累加之和
 65 
 66     static double total; //所有账户的总金额
 67 
 68                          //记录一笔账，date为日期，desc为说明,amount为金额
 69 
 70     void record(const Date &date, double amount,const std::string &desc);
 71 
 72     //报告错误信息
 73     void error(const std::string &msg)const;
 74     //获得到指定日期为止的存款金额按日累积值
 75     double accumulate(const Date &date) const
 76 
 77     {
 78 
 79         return accumulation + balance*date.distance(lastDate);
 80 
 81     }
 82 
 83 public:
 84 
 85     //构造函数
 86 
 87     SavingsAccount(const Date &date, const std::string &id, double rate);
 88 
 89     const std::string &getId() const { return id; }
 90 
 91     double getBalance() const { return balance; }
 92 
 93     double getRate() const { return rate; }
 94 
 95     static double getTotal() { return total; }
 96 
 97     void deposit(const Date &date, double amount, const std::string &desc); //存入现金
 98 
 99     void withdraw(const Date &date, double amount,const std::string &desc); //取出现金
100 
101                                             //结算利息，每年1月1日调用一次该函数
102 
103     void settle(const Date &date);
104 
105     //显示账户信息
106 
107 
108 
109     void show() const;
110 
111 };
112 double SavingsAccount::total = 0;
113 
114 //SavingsAccount类相关成员函数的实现
115 
116 SavingsAccount::SavingsAccount(const Date &date, const string &id, double rate): id(id), balance(0), rate(rate), lastDate(date), accumulation(0)
117 
118 {
119     date.show();
120     cout <<  "\t#" << id << "  created" << endl;
121 
122 }
123 
124 void SavingsAccount::record(const Date &date, double amount, const string &desc)
125 
126 {
127 
128     accumulation = accumulate(date);
129 
130     lastDate = date;
131 
132     amount = floor(amount * 100 + 0.5) / 100; //保留小数点后两位
133 
134     balance += amount;
135 
136     total += amount;
137     date.show();
138 
139     cout <<"\t#" << id << "\t" << amount << "\t" << balance << "\t" <<desc<< endl;
140 
141 }
142 void SavingsAccount::error(const string &msg)const
143 
144 {
145 
146     cout<<"Error(#"<<id<<"):"<<msg<<endl;
147 
148 }
149 
150 void SavingsAccount::deposit(const Date &date, double amount, const string &desc)
151 
152 {
153 
154     record(date, amount,desc);
155 
156 }
157 
158 void SavingsAccount::withdraw(const Date &date, double amount, const string &desc)
159 
160 {
161 
162     if (amount > getBalance())
163         error("not enough money");
164         //cout << "Error:not enough money" << endl;
165 
166     else
167 
168         record(date, -amount,desc);
169 
170 }
171 
172 void SavingsAccount::settle(const Date &date)
173 
174 {
175 
176     double interest = accumulate(date)*rate / date.distance(Date(date.getYear()-1, 1, 1)); //计算年息
177 
178     if (interest != 0)
179 
180         record(date, interest,"interest");
181 
182     accumulation = 0;
183 
184 }
185 
186 void SavingsAccount::show() const
187 
188 {
189 
190     cout  << id << "\tBalance:" << balance;
191 
192 }
193 int main(){
194     Date date(2008, 11, 1);
195 
196     //建立几个账户
197     SavingsAccount accounts[] = {
198 
199     SavingsAccount(date, "03755217", 0.015),
200 
201     SavingsAccount(date, "02342342", 0.015)
202 
203 
204     };
205     const int n = sizeof(accounts) / sizeof(SavingsAccount);//账户总数
206 
207 
208     //11月的几笔账目
209 
210     accounts[0].deposit(Date(2008, 11, 5), 5000, "salary");
211     accounts[1].deposit(Date(2008, 11, 25), 10000, "sell stock 0323");
212     //12月的几笔账目
213     accounts[0].deposit(Date(2008, 12, 5), 5500, "salary");
214     accounts[1].withdraw(Date(2008, 12, 20), 4000, "buy a laptop");
215     //结算所有的账户并输出各个账户信息
216     cout << endl;
217     for (int i = 0;i < n;i++) {
218         accounts[i].settle(Date(2009, 1, 1));
219         accounts[i].show();
220         cout << endl;
221     }
222     cout << "Total: " << SavingsAccount::getTotal() << endl;
223     return 0;
224 }