Need help writing a function.

[gator6688]

I have to write a program using an enterData() function and a printCheck() function. It has to be accepted by enterData() and passed to printCheck(). I need to be able to input the date, a persons first and last name, and an amount. Can anyone help me get started?

[sicarie]

I have to write a program using an enterData() function and a printCheck() function. It has to be accepted by enterData() and passed to printCheck(). I need to be able to input the date, a persons first and last name, and an amount. Can anyone help me get started?

So when you enter data, what type are you reading in? What will you do if it fails? How will you test the fail on condition? Do you know how to return values?

[gator6688]

I hardly know any of this stuff. I don't want anyone to do it for me but I would like someone to take the time to help me and talk me through it so that I learn it.

[oler1s]

I don't want anyone to do it for me but I would like someone to take the time to help me and talk me through it so that I learn it.

Sure, not a problem. But what's your question? If you're not sure where to get started, then look at the question at hand. There are these two central functions, and it's obvious that you need to enter data before you can print a check. So focus on getting enter data to work perfectly for now. Forget about print check.

You have four objects to store. Start with one of them. Let's make it easy. Start with the first name. How would you store a name? Is this C or C++? Your options vary depending on that. So focus on just one thing right now. Get enterData working, and for now, all it does is ask the person for his first name, and store that in the program.

If you aren't sure how to go about even that much, then the problem here is just not knowing your language at all. The solution is to go to cplusplus.com or cprogramming.com, or open up your textbooks, and do some reading.

[gator6688]

Well i'm pretty sure that this isn't a user prompted program so I don't think I should be asking for the first name should I?

[gator6688]

This program is C++.

[gator6688]

Would this be the correct prototype?

[gator6688]

Would this prototype be correct?

void enterData(int date, char firstName, char lastName, double amount);

[gator6688]

Does this program look any better and how do I use printCheck to assign the data to the check?

[Ganon11]

Well, it actually DOES look like this program will be user-driven, so you'll have cin's to take care of setting values for those variables. However, let's talk about local variables:

void enterData(int date, char firstName, char lastName, double amount);

What you have here are 4 copies of variables that you (presumably) will declare in main() and pass to enterData(). By the name of enterData, you should be reading data into these variables, which can then be used back in main(). However, these are only copies. When you call enterData:

enterData(myDate, myFirstName, myLastName, myAmount);

the computer takes the values that myDate, myFirstName, etc. had, makes a copy of them, and gives them to the enterData function to work with. You then read values into these copies. Once the function is done, these copies are destroyed - and you've done nothing to the original copies of those variables!

We need a way to let enterData see those variables. One (very bad) way would be to declare these variables outside of main(). That way, every function can see the varables. You don't need parameters for your enterData function anymore - it should just get the variables directly. This is a bad approach, however, because printCheck might be called before these variables are given values. That, and countless other reasons, are why you should not use these 'global variables'. So what do you do?

Use 'pass by reference':

void enterData(int &date, char &firstName, char &lastName, double &amount);

Ahh...this will work. That little & sign means that, instead of receiving a copy, the function will basically receive the actual variable. Anything done to the variables in enterData will be reflected back in main(). Cool, eh?

As a side note...should you be using chars for firstName and lastName? Wouldn't an std::string be better? Or (if you like C legacy style), a character array (called a CString)?

[gator6688]

I did change it to string. Does this look any better?

[gator6688]

Could someone look this over and tell me what else I could do?

#include "stdafx.h"
#include <iostream>
#include <string>
using namespace std;
 
void enterData(string todaysDate, string firstName, string lastName, double amount);
void printCheck(string todaysDate,string firstName,string lastName,double amount);
 
 
 
 
int _tmain(int argc, _TCHAR* argv[])
{
 
    string todaysDate,firstName, lastName;
    double amount;
 
 
 
    cout << "Enter today's date: ";
    cin  >> todaysDate;
    cout << "Enter the first name: ";
    cin  >> firstName;
    cout << "Enter the last name: ";
    cin  >> lastName;
    cout << "Enter the amount: ";
    cin  >> amount;
 
 
    cout << "Zzyz Corp                                      Date: (today's date)"<<endl;
    cout << "1164 Sunrise Avenue                                        "<<endl;
    cout << "Kalispell, Montana\n                                         "<<endl;
 
    cout << "Pay to the order of: (firstName lastName)      $ (amount)\n "<<endl;
    cout << firstName << " " <<  lastName;
    cout << "      $" << amount << endl;
 
 
    cout << "UnderSecurity Bank                                         "<<endl;
    cout << "Missoula, MT                                               "<<endl;
    cout << "                                                ____________________"<<endl;
    cout << "                                                Authorized Signature";
 
    cout << endl << endl;
    return 0;
}

[gator6688]

Anyone have any suggestions?

[gator6688]

Anyone out there with any suggestions?

[Ganon11]

Yes, there is: however, remember that this is a site with volunteers that are willing to help you out. Please have a little more patience when waiting for people to help you out.

It looks like you aren't even using your functions! You declare them, but then have all the code inside main(). Try actually writing the functions.

[gator6688]

Could you please give me an example of declaring a function.

[Ganon11]

You've already declared your functions:

void enterData(string Date, string FirstName, string LastName, double amount);

Thia is an example of declaring a function. You have to define it now:

void enterData(string Date, string FirstName, string LastName, double amount) {
   // Your code here.
}

[oler1s]

Could you please give me an example of declaring a function.

We could, but we won't. We're here to help you learn, but if you need us to show you how to declare a function, the problem is you just aren't doing the necessary reading. If you are struggling with writing functions, I suggest reading some online tutorials (preferably the ones at cplusplus.com or cprogramming.com or your textbook).

[gator6688]

How long would it take you to write this program?

[gator6688]

Plus, all the tutorials I read is for a function adding two intergers a+b which is easy. I have to be able to input the info into one function and have it passed on to another and have it displayed in the check. Yes for most of you it would probably be easy but I have only been learning C++ for 5 weeks and most of this stuff is still difficult for me.

[gator6688]

Somebody please put me out of my misery and write this for me. Please.

[Ganon11]

The experts on this site are more than happy to help you with your problems but they cannot do your assignment/program for you. Attempt the assignment/program yourself first and post questions regarding any difficulties you have or about a particular function of the code that you don't know how to achieve.

Please read the Posting Guidelines and particularly the Coursework Posting Guidelines.

Then when you are ready post a new question in this thread.

MODERATOR

We've given you a lot of help so far. You've got the code in your function! You've already written the majority of your program! All you need to do is copy and paste the relevant code and put it in the correct function - as we've already demonstrated. There is nothing else we can do for you.

[gator6688]

How can I get the data I enter to be sent to the check? Also, how come when it asks me for the first and last name and amount it all goes on the same line?

#include "stdafx.h"
#include <iostream>
#include <string>
using namespace std;
 
string todaysDate;
string firstName;
string lastName;
double amount;
 
void enterData();
void printCheck();
 
 
int _tmain(int argc, _TCHAR* argv[])
 
{
    enterData();
    printCheck();
 
    return 0;
}
 
void enterData()
{
 
 
    cout << "Enter today's date: ";
    cin  >> todaysDate;
    cout << "Enter the first name: ";
    cin  >> firstName;
    cout << "Enter the last name: ";
    cin  >> lastName;
    cout << "Enter the amount: ";
    cin  >> amount;
}
 
void printCheck()
{
    cout << "Zzyz Corp                                      Date: (today's date)"<<endl;
    cout << "1164 Sunrise Avenue                                        "<<endl;
    cout << "Kalispell, Montana\n                                         "<<endl;
 
    cout << "Pay to the order of: (string firstName lastName)      $ (amount)\n "<<endl;
 
 
 
    cout << "UnderSecurity Bank                                         "<<endl;
    cout << "Missoula, MT                                               "<<endl;
    cout << "                                                ____________________"<<endl;
    cout << "                                                Authorized Signature";
 
    cout << endl << endl;
 
}

[sicarie]

How can I get the data I enter to be sent to the check?

You declare check to be void check() - so you're not passing anything to it, and you are not returning anything from it. You need to pass it the relevant variables, and return the relevant type.

Also, how come when it asks me for the first and last name and amount it all goes on the same line?

Because you haven't told it not to. I would recommend putting a newline characters around what you want to be on a different line. The newline char is '\n', and can be incorporated into any string to create a new line.