C Program Homework

CS1325 – F16 Homework #7-1

Assigned Nov 27, due Dec 6 at 11:59 PM

This homework assignment gives you the opportunity to practice structures, pointers to structures,

arrays of pointers to structures, dynamic allocation and file input/output.

HW7-1 (Graded out of 100) Write a program that uses a structure to store grocery product information. For each product we store the following information in a structure: - PLU code: Product Look Up Code. Unique for each product, stored as a string.

- Product Name,

- Product Sales Type: 0 = per unit, 1 = per pound

- Price per Pound or price per unit,

- Current Inventory Level.

The structures are accessed through an array of pointers, where each pointer points to a structure.

Your program should read grocery product information from the “productData.txt” file, and populate the structures. Below is an example of file content. Each line in the file corresponds to one product. A001 Apples 1 0.90 21

A002 Peaches 1 0.82 11

A006 Avocados 0 1.54 27

A008 Mangos 0 1.69 19

A009 Strawberries_case 0 12.5 8

4261 Rice_1_Lb_bag 0 0.49 107

Then the program should display a menu for the user to choose from: 1 – Checkout 2 – Close and exit Checkout If the user chooses checkout, the user can purchase multiple products in each checkout. The user is asked to enter the PLU code, then the quantity (weight or # of units, depending on the sales type) for each product. The program keeps up with the total cost ($). The user can enter 0 for a PLU to indicate the end of checkout. The program then displays the total price, and displays the menu again. The program should do input validation on the quantity, which must be positive. If the quantity is not positive, the user is asked to reenter. Your program is not required to do input validation on the PLU and ask the user to reenter, but your program must display an error if the PLU entered cannot be found. Your program should make sure the quantity bought is not more than the inventory level. For example, if the user wants to buy 10 apples, but only 5 apples are in the inventory, the program will sell only 5 apples. The inventory level should be automatically updated with each purchase. Close and exit

If the user chooses this option, all the updated product information (updated inventory level) should be displayed on the screen and written into the “updatedProductData.txt” file, then the program exits.

Additional requirements – Make sure you meet all the requirements to avoid losing points 1. Follow the requirements in the “Homework Notes”.

2. To ensure consistency in the submissions, your program must do the following:

a) Use this structure struct product

{

char PLU[PLU_LENGTH]; // set PLU_LENGTH to 10

char name[PRODUCT_NAME_LENGTH]; // set PRODUCT_NAME_LENGTH to 20

int salesType;

double unitPrice;

double inventoryLevel;

};

typedef struct product Product;

b) Array definition const int SIZE = 100; // Assume there are at most 100 products

Define an array of pointers to Product, of size SIZE, locally in main.

Your program must work for any product data file that has the same format as “productData.txt”, where

the number of products is variable, but less than or equal to 100.

c) Functions You are required to implement your program with at least these 3 functions. You are encouraged to

implement more functions to make your program more modular.

To read a file and populate the structures, call a function with the following prototype and description:

/*********************************************************************

***********************

This function takes as arguments a file name and an array of pointers

to Product, along with

the max size of the array. It opens the file and reads the inventory

from the file.

It reads line by line, where each line corresponds to a product.

For each product, it dynamically allocates a Product structure and

assigns the pointer to an element of the array.

It populates the structure with the data read.

The structure content is displayed. The function terminates when there

is no more data in the file

or when the array is full. It also terminates upon error condition.

It returns the number of products if all the data was valid, -1 if

file could not be opened.

**********************************************************************

***********************/

int readInventory(char * fName, Product * arrayProd[], size_t

max_size);

For the checkout, implement a function with the following prototype and description:

/*********************************************************************

***********************

This function does the checkout. It takes as argument the array of

pointers to Product, and

the actual number of products in the inventory. It reads the PLU and

quantity from the user.

The function does input validation on the quantity, which must be > 0.

If the quantity is not positive, the user is asked to reenter.

The function does not do input validation on the PLU and ask the user

to reenter, but

it displays an error if the PLU entered cannot be found.

The function updates the product data to reflect the user's purchase,

then

prompts the user for more product purchases.

The user types a PLU of zero when done. The function returns the total

purchase price.

**********************************************************************

***********************/

double checkout(Product * arrayProd[], int nProd);

For the close and exit, implement a function with the following prototype and description: /*********************************************************************

***********************

This function displays the updated product data on the screen and

writes the data into a file.

The function takes as arguments the file name, the array of pointers

to Product and the actual number of

products in the inventory. Returns true if file open was successful,

false otherwise.

**********************************************************************

***********************/

_Bool updateInventory(char * fName, Product * arrayProd[], int nProd);

d) Outline of main

To demonstrate your program, write a main function with the following outline. The file “productData.txt” is on eLearning.

Call readInventory to read product data from file “productData.txt”

Display menu and get user’s choice

While (user’s choice is not Close and exit)

Call checkout

End while

Call updateInventory to write updated product data into file

“updatedProductData.txt”

You are allowed to hard code all the file names.

Suggestions for Implementation The product data file is formatted such that there are 5 items (PLU, name, type, unit price and inventory level) for each product. fscanf() returns the number of items actually read. To determine if there is no more data in the file, read the value returned by fscanf and check if it is equal to 5. itemsRead = fscanf(fPtr, "%s%s%d%lf%lf", plu, pName, &type, &price,

&level);

Expected Output Below is an example of output if your implementation is correct. For your convenience, to avoid typing,

you can use the file “1325-F16-HW7-1-Input” on eLearning. Copy the content of the file, then in the

CodeBlocks window, right click the mouse. That will automatically paste the input.

After close and exit, the content of file “updatedProductData.txt” should be:

Extra Credit You can earn up to 15 points extra credit if, in addition to the above, your program prints on the screen

a list of items and their prices, along with the total price, at the end, and only at the end of each

checkout. This is the equivalent of a sales receipt.

You may need to make the necessary adaptations to the functions (parameter list, etc.) from the basic

version. If you attempt the extra credit, please indicate it clearly at the beginning of your program. The

content of file “updatedProductData.txt” should be the same as in the basic version.