【第四章】 个人银行账户管理程序 案例实现
#include<iostream>
#include<cmath>
using namespace std;
class SavingsAccount //储蓄账户类
{
private:
int id; //账号
double balance; //余额
double rate; //存款的年利率
int lastDate; //上次变更余额的日期
double accumulation; //余额按日累加之和
static double total; //所有账户的总金额
//记录一笔账，date为日期，desc为说明
void record(int date, double amount);
//获得到指定日期为止的存款金额按日累积值
double accumulate(int date) const
{
return accumulation + balance*(date - lastDate);
}
public:
//构造函数
SavingsAccount(int date, int id, double rate);
int getId() const { return id; }
double getBalance() const { return balance; }
double getRate() const { return rate; }
void deposit(int date, double amount); //存入现金
void withdraw(int date, double amount); //取出现金
//结算利息，每年1月1日调用一次该函数
void settle(int date);
//显示账户信息
void show() const;
};
SavingsAccount::SavingsAccount(int date, int id, double rate)
: id(id), balance(0), rate(rate), lastDate(date), accumulation(0)
{
cout << date << " #" << id << " is created" << endl;
}
void SavingsAccount::record(int date, double amount)
{
accumulation = accumulate(date);
lastDate = date;
amount = floor(amount * 100 + 0.5) / 100; //保留小数点后两位
balance += amount;
cout << date << " #" << id << " " << amount << " " << balance << endl;
}
void SavingsAccount::deposit(int date, double amount)
{
record(date, amount);
}
void SavingsAccount::withdraw(int date, double amount)
{
if (amount>getBalance())
cout << "Error:not enough money" << endl;
else
record(date, -amount);
}
void SavingsAccount::settle(int date)
{
double interest = accumulate(date)*rate / 365; //计算年息
if (interest != 0)
record(date, interest);
accumulation = 0;
}
void SavingsAccount::show() const
{
cout << "#" << id << " Balance:" << balance;
}
int main()
{
//建立几个账户
SavingsAccount sa0(1, 21325302, 0.015);
SavingsAccount sa1(1, 58320212, 0.015);
//几笔账目
sa0.deposit(5, 5000);
sa1.deposit(25, 10000);
sa0.deposit(45, 5500);
sa1.withdraw(60, 4000);
//开户后第90天到了银行的计息日，结算所有账户的年息
sa0.settle(90);
sa1.settle(90);
//输出各个账户信息
sa0.show(); cout << endl;
sa1.show(); cout << endl;
return 0;
}
ps：
配套教材：郑莉《c++程序设计语言》
课程：学堂在线《c++程序设计语言》