一个活期储蓄帐户包括账号(id),余额(balance),年利率(rate)等信息,还包括显示账户信息(show),存款(desposit),取款(withdraw),结算利息(settle)等操作。为此设计一个savingaccount类,将id,balance,rate,作为其成员数据,将show,deposit,withdraw,settle,均作为其成员函数。无论是存款取款还是结算利息,都需要修改当前的余额并且将余额的变动输出,这些公共操作由私有成员函数record来执行。
根据所学知识代码持续完善中……
#include <iostream> #include<cmath> using namespace std; class SavingAccount{ private: int id; //账户 double balance; //余额 double rate; //年利率 int lastdate; //余额上一次变化的日期 double accumulation; //余额按日累加之和 int accumulate(int date); //获得到指定日期位置的存款累计值 double getbalance(){return balance;} double getrate(){return rate;} void record(int date,double amount); //记账 public: SavingAccount(int date,int id,double rate); //构造函数 void deposit(int date,double amount); //存款 void withdrawl(int date,double amount); //取款 void show(); //显示余额 void settle(int date); //结算利息,每年一月一日调用此函数 }; //类的成员函数的实现 SavingAccount::SavingAccount(int date,int id,double rate):id(id),balance(0),rate(rate),lastdate(date),accumulation(0){ cout<<"#"<<id<<"is created"<<endl; } int SavingAccount::accumulate(int date){ return accumulation+balance*(date-lastdate); } void SavingAccount::record(int date,double amount){ lastdate=date; amount=floor(100*amount+0.5)/100; //floor为向下取整函数,此处可以做到保留两位小数 balance+=amount; cout<<date<<"\t#"<<id<<"\t"<<amount<<"\t"<<balance<<endl; } void SavingAccount::deposit(int date,double amount){ record(date,amount); } void SavingAccount::withdrawl(int date, double amount){ if(amount>balance) cout<<"not enough money"<<endl; else record(date,-amount); } void SavingAccount::show(){ cout<<"#"<<id<<"\tBalance"<<balance<<endl; } void SavingAccount::settle(int date){ double interest=accumulate(date)*rate/365; //计算年息 if(interest!=0) record(date,interest); accumulation=0; } int main() { SavingAccount s1(0,11111,0.015); SavingAccount s2(1,22222,0.015); s1.deposit(5,5000); s2.deposit(25,10000); s1.deposit(45,5500); s2.withdrawl(60,11000); s1.settle(90); s2.settle(90); s1.show(); s2.show(); return 0; }