"simple" library program

[antwan]

I keep getting linker errors after I run this program and I cannot figure out why. Please help.

#include <iostream>
#include <iomanip>
#include <cmath>

using namespace std;

// Function Prototypes
double CashierMod();
int InventoryMod();
double ReportMod();
char BookInfo();
int menu();

const int SIZE=50;
const int PRECISION=2;
const int NUM_BOOKS=10;
const double Tax = 0.06;

double Price, subTotal, totalSale;
char date;

struct Store
{
char ISBN [SIZE];
char title [SIZE];
char author [SIZE];
char publisher [SIZE];
char dateAdded [SIZE];
int onHand;
double wholeCost;
double retailCost;
};


char BookInfo()
{
Store BookInfo;

cout<<"Enter the book's ISBN number: \n";
cin.getline(BookInfo.ISBN, SIZE);
cout<<"Enter the title of the book: \n";
cin.getline(BookInfo.title, SIZE);
cout<<"Enter the author of the book: \n";
cin.getline(BookInfo.author, SIZE);
cout<<"Enter the publisher of the book: \n";
cin.getline(BookInfo.publisher,SIZE);
cout<<"Enter the date the book was added: \n";
cin.getline(BookInfo.dateAdded, SIZE);
cout<<"Enter the quantity of this book on hand: \n";
cin>>BookInfo.onHand;
cout<<"Enter the wholesale cost of the book: \n";
cin>>BookInfo.wholeCost;
cout<<"Enter the retail cost of the book: \n";
cin>>BookInfo.retailCost;

system ("pause");
return 0;

};

// The Main Module.
int main ()
{
int selection;

cout << fixed << showpoint << setprecision(2);
do
{
selection = menu();
switch(selection)
{
case 1 : CashierMod();
break;
case 2 : InventoryMod();
break;
case 3 : ReportMod();
break;
case 4 : BookInfo();
break;
case 5 : cout << "Exiting program.\n\n";
}
} while (selection != 5);
return 0;

}

// The Main Menu Module.
int menu()
{
int choice;
cout << "S & E Book Store\n";
cout << "\tMain Menu\n";
cout << "----------------\n";
cout << "1) Check Out\n";
cout << "2) Inventory\n";
cout << "3) Reports\n";
cout << "4) Book Information\n";
cout << "5) Exit Program\n";
cout << "Enter 1, 2, 3, 4, or 5: \n";
cin >> choice;
while (choice < 1 || choice > 5) // Validate input
{
cout << "Invalid Selection. Enter 1, 2, 3, 4, or 5: ";
cin >> choice;
}
return choice;


}

// The Cashier Module.
double CashierMod (double SubTotal, double Sales_Tax, double TotalSale)
{
int ISBN, Qty;
char date [SIZE];
cout << "S & E Book Store\n";
cout << "\tCash Register Menu\n";
cout << "----------------\n";
cout << "Please enter today's date: \n";
cin >> date; // Example: 10-Nov-2008.
cout << "Enter a valid ISBN: \n";
cin >> ISBN;
while (ISBN != 123)
{
cout << "Invalid selection. Enter a valid ISBN: \n";
cin >> ISBN;
}

cout << "Enter quantity for purchase: \n";
cin >> Qty;

cout << fixed << showpoint << setprecision(2);

// Calculate subtotal.

SubTotal = ISBN * Qty;
cout << "Subtotal: \n" << SubTotal;
// Calculate tax.
Sales_Tax = SubTotal * Tax;
cout << "Sales Tax: \n" << Sales_Tax;
// Calculate Total Sale.
TotalSale = SubTotal + Sales_Tax;
cout << "Total: \n" << TotalSale;


system ("Pause");
return 0;
}


// The Inventory Database Module.
int InventoryMod()
{
int choice;

while (true)
{
//Display the menu and get a choice
cout << endl;
cout << "S & E Book Store\n";
cout << "Inventory Database\n";
cout << "------------------\n";
cout << "1. Look-Up a Book\n";
cout << "2. Add a Book\n";
cout << "3. Edit a Books Record\n";
cout << "4. Delete a Book\n";
cout << "5. Return to the Main Menu\n";
cout << endl;
cout << "Enter your choice:" << endl;
cin >> choice;
switch (choice)
{
case 1: void lookUpbook();
break;
case 2: void addBook();
break;
case 3: void editBook();
break;
case 4: void deleteBook();
break;
case 5: cout << "Returning to main menu." << endl;
break;
}

//Validate and process the menu choice.
while (choice < 1 || choice > 5)
{
cout << "Please enter a number between one and five." << endl;
cin >> choice;
}
} while (choice != 5);
return 0;
}

//Add stub functions for inventory database

void lookUpBook()
{
//Get the title of the book to search for
cout << "Enter the title of the book you wish to search for. " << endl;

}


// The Report Module.
double ReportMod (double InvList, double WholeSaleValue, double RetailValue, double QtyList, double QtyCost, double AgeList)
{
int choice;

cout << "S & E Book Store\n";
cout << "\t Reports\n";
cout << "----------------\n";
cout << "1) Inventory Listing\n";
cout << "2) Inventory Wholesale Value\n";
cout << "3) Inventory Retail Value\n";
cout << "4) Listing by Quantity\n";
cout << "5) Listing by Cost\n";
cout << "6) Listing by Age\n";
cout << "7) Return to the Main Menu\n";
cin >> choice;
while (choice < 1 || choice > 7) // Validate input
{
cout << "Invalid Selection. Enter 1, 2, 3, 4, 5, 6, or 7: ";
cin >> choice;
}
return choice;

}

// The Book Info Module.
char BookInfo(int ISBN, char Title, char Author, char Publisher, char DateAdded, int QtyHand, int WholeCost, int RetailCost)
{
cout << "S & E Book Store\n";
cout << "Book Information\n";
cout << "----------------\n";
cout << "ISBN: \n";
cout << "Title: \n";
cout << "Author: \n";
cout << "Publisher: \n";
cout << "Date Added: \n";
cout << "Quantity on Hand: \n";
cout << "Wholesale Cost: \n";
cout << "Retail Price: \n";

system ("Pause");
return 0;

}

[helios]

Well? What do they say?

[antwan]

[Linker error] undefined reference to `CashierMod()'
[Linker error] undefined reference to `ReportMod()'
Id returned 1 exit status

Sorry about the huge post. How do I paste code in the blue boxes?

[giantMidget]

In your first switch statement, you have:

case 1 : CashierMod();

case 3 : ReportMod();

but the you have CashierMod(double, double, double) and ReportMod (double, double, double, double, double, double)

GM

[rahulcrjk]

You have to go through tutorials for functions again.
Function declaration should give the skeleton. For example when u call a function if u expect to pass some values they must come in the bracket following it.
double CashierMod(); // This is your function prototype

double CashierMod (double SubTotal, double Sales_Tax, double TotalSale)
//This is ur function definition

The above two does not match.
In the function prototype u r telling the compiler that "somewhere in th e program u will find a function CashierMod and while calling that function I will not be passing any argument to it. Also u will find a argumentless definition somewhere else."

But compiler cannot find such a definition.

In C++, by function overloading concepts, CashierMod() and CashierMod (double SubTotal, double Sales_Tax, double TotalSale) are 2 different functions.


Also

double CashierMod (double SubTotal, double Sales_Tax, double TotalSale)

...function will be called only if you call CashierMod with three double arguments. Also u need to provide a similar function prototype.

I have not gone thru ur program in detail but one thing which came to my notice was:

double CashierMod (double SubTotal, double Sales_Tax, double TotalSale)

Here u have used the double SubTotal, double Sales_Tax, double TotalSale
to initialize normal variables not variables declared for holding values which u will be passing, while calling the function. etc etc