简单的银行交易系统

================================================================
            biz.h
================================================================

//opration
/* p : password of account
b : balance of account
*/
long create(int p, double b);
void save(double sum);
int withdraw(int p, double sum);
double query(int p);
long generateId();

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            biz.cpp

================================================================

#include <iostream>
using namespace std;

static int id;
static int passwd;
static double balance;

long generateId()
{
static int id = 1;
return id++;
}
long create(int p, double b)
{
id = generateId();
passwd = p;
balance = b;
return id;
}
void save(double sum)
{
balance += sum;
}
int withdraw(int p, double sum)
{
if(p != passwd)
{
cout << "Invalid password!" << endl;
return -1;
}
if(balance < sum)
{
cout << "No enough money!" << endl;
}
balance -= sum;
return 0;
}
double query(int p)
{
if(p != passwd)
{
cout << "Invalid password!" << endl;
return -1;
}
else
return balance;
}

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            menu.h

================================================================

int showMenu();
void createMenu();
void withdrawMenu();
void queryMenu();

================================================================

            menu.cpp

================================================================

 

#include <iostream>
#include "biz.cpp"
using namespace std;

int showMenu()
{
cout << "Create -------> 1" << endl;
cout << "Save   -------> 2" << endl;
cout << "Withdraw -----> 3" << endl;
cout << "Query --------> 4" << endl;
cout << "Exit ---------> 0" << endl;
cout << "Enter your choice:";
int c;
cin >> c;
if(!cin)
return -1;
else
return c;
}
void createMenu()
{
int passwd;
double balance;
cout << "\t Enter password >";
cin >> passwd;
cout << "\t Enter balance >";
cin >> balance;
long id = create(passwd, balance);
cout << "========================" << endl;
cout << "Create acount OK! id = " << id << endl;
cout << "========================" << endl;
}
void saveMenu()
{
double sum;
cout << "\t Enter sum >";
cin >> sum;
save(sum);
cout << "========================" << endl;
cout << "Save money OK!" << endl;
cout << "========================" << endl;
}
void withdrawMenu()
{
int passwd;
double sum;
cout << "\t Enter passwd >";
cin >> passwd;
cout << "\t Enter sum >";
cin >> sum;
int ret = withdraw(passwd, sum);
if(ret == 0)
{
cout << "========================" << endl;
cout << "Withdraw successful!" << endl;
cout << "========================" << endl;
}
}
void queryMenu()
{
int passwd;
cout << "\t Enter passwd >";
cin >> passwd;
double ret = query(passwd);
if(ret != -1)
{
cout << "========================" << endl;
cout << "BALANCE: $" << ret << endl;
cout << "========================" << endl;
}
else
{
cout << "========================" << endl;
cout << "Invalid passwd" << endl;
cout << "========================" << endl;
}
}

================================================================

            main.cpp

================================================================

 

#include <iostream>
#include "menu.cpp"
using namespace std;
int main()
{
int c = 0;
do
{
c = showMenu();
if(c == -1) { break; }
switch(c)
{
case 1:
createMenu();
break;
case 2:
saveMenu();
break;
case 3:
withdrawMenu();
break;
case 4:
queryMenu();
break;
case 0:
cout << "========================" << endl;
cout << "Good Bye!" << endl;
cout << "========================" << endl;
break;
default:
cout << "========================" << endl;
cout << "Invalid option, try again." << endl;
cout << "========================" << endl;
break;
}
}while(c != 0);
return 0;
}