Returning a value in a void function

[kultrva]

How would one go about returning a value in a type void function? I would assume that it is possible in some way because my professor has assigned my class an assignment in which we have to do just that. We have to make 5 functions, all type void to integrate with our previous project. Here is the prompt for the first function:

getBalance is a function that will open a file called balance.txt, and retrieve the credit value. If there is nothing in the balance.txt file, or it doesn’t exist, assume that the user wants to begin a new account, with 50 credits. getBalance is a void function that returns either the balance from the file or 50 credits.

I understand the fileio part, but I don't know how to return balance in a void function. Would anybody be willing to point me in the right direction? I'm not asking for any code, just advice. Thanks.

[kyle11778]

couldn't you use a pointer?
http://www.cplusplus.com/doc/tutorial/pointers/

int& credit;
ifstream file("");

getBalence(credit, file);

//...

void getBalence(int* credit,ifstream file){
// your code
}

i am just typing off the top pf my head, just giving you a direction

[Aeon221]

You've got a value and some associated functions. Use a class. Here's an example of what a class would look like for your issue.

class  Bank_account {
public:	
	int balance;
	Bank_account() {balance =0;}
        Bank_account(int amount){balance = amount;}

void get_balance(){
	if (condition)
		dosomethingelse;
	else (condition)
		dosomethingelse;
	}
}

int main(){
	Bank_account myaccount;
        vector<Bank_account> thebank;
        thebank.push_back(myaccount);
	myaccount.get_balance();
	cout << thebank.at(0).balance;
}

Loop input into an object and toss the object into the vector. Then loop through checking balance and writing stuff to the new file.

[kfmfe04]

The simplest solution:

void sum( int& result, int a, int b )
{
  result = a + b;
}