Verifying a pincode, ATM program - c++

Question

I'm writing a program that simulates an ATM and I'm having problems with the account arrays in the program. The account arrays hold the account number, pin code, and account balance. The very first function in the code allows the user to log in with their pin and account number, but I'm having issues comparing the user input to the account array:
#include <iostream>
#include <string>
using namespace std;
class Account
{
private: int accountNum;
int accountPin;
double accountBalance;
int setPin();
int setAccountNum();
public: Account();
Account(int, string, double);
double setAccountBalance(int) ;
int getAccountNum();
int confirmPin(string) ;
double updateBalance(double) ;
};
void confirmPin(string accountPin, int accountNum)
{
//confirm pin segment
// returns true or false value, allows access to account balance information
}
int main () {
Account account[3] =
{
{123, "abc123", 100.00}, {456, "def456", 50.00},{789, "ghi789", 500.63}
};
int option;
cout << "LOGIN\nEnter Account#: "<< endl;
cin >> accountNum;
cout << "Enter password";
cin >> accountPin;
//confirm pin function
I coded as much as I could at the moment. I have no clue where to start in terms of comparing the input to the account info. Thanks in advance for any help!

Answer 1

Here are some examples to get you started.
Overload equality comparison
class Account
{
//...
public:
bool operator==(const Account& a) const
{
if (accountNum != a.accountNum) return accountNum < a.accountNum;
else
{
if (accountPin != a.accountPin) return accountPin < a.accountPin;
else
{
double difference = abs(accountBalance - a.accountBalance);
if (difference < 1.0E-6) return true;
}
return false;
}
};
This allows you to input one instance and compare to another instance for equality.
Create Comparison Function
Add a method to your class that compares account numbers:
class Account
{
//...
public:
bool is_equal_account_number(const Account& a) const
{
return accountNum == a.accountNum;
}
};
The above method allows you to compare only the account numbers. This may be useful since duplicate account numbers are probably not allowed.
Compare By Value
Another example is to write a method that will compare the account number with a given account number.
class Account
{
//...
public:
bool same_account_number(const int acct_num) const
{ return accountNum == acctnum);
};
The above are some examples of comparing accounts. There are others, like employing getter functions and comparing those values.