# Program: Structure pointers and Functions

## **Problem Statement**

Create a C program that involves structures and pointers. The program should define a structure named `Item` with members:

* `itemName` (a pointer to a character array)
* `quantity` (an integer)
* `price` (a floating-point number)
* `amount` (a floating-point number, calculated as `quantity * price`)

The program should have two functions:

1. **`readItem` Function:**
   * Takes a structure pointer of type `Item` as a parameter.
   * Allocates memory for the `itemName` pointer.
   * Reads product name, price, and quantity from the user and stores them in the passed-in structure.
2. **`printItem` Function:**
   * Takes a structure pointer of type `Item` as a parameter.
   * Prints the contents of the structure, including product name, price, quantity, and total amount.

In the `main` function:

* Declare an `Item` structure and a pointer to the `Item`.
* Allocate memory for the `itemName` pointer.
* Pass the `Item` pointer to both the `readItem` and `printItem` functions.
* Finally, free the allocated memory for the `itemName` pointer.

## **Algorithm**

1. Declare a structure `Item` with the required members.
2. Implement the `readItem` function:
   * Allocate memory for the `itemName` pointer.
   * Read product name, price, and quantity from the user.
   * Store the input values in the passed-in structure.
3. Implement the `printItem` function:
   * Print the product name, price, quantity, and total amount.
4. In the `main` function:
   * Declare an `Item` structure and a pointer to the `Item`.
   * Allocate memory for the `itemName` pointer.
   * Pass the `Item` pointer to the `readItem` function.
   * Pass the `Item` pointer to the `printItem` function.
   * Free the allocated memory for the `itemName` pointer.

## **Program**

```c
#include <stdio.h>
#include <stdlib.h>

struct Item {
    char *itemName;
    int quantity;
    float price;
    float amount;
};

void readItem(struct Item *itemPtr);
void printItem(const struct Item *itemPtr);

int main() {
    struct Item item;
    struct Item *itemPtr = &item;

    // Allocate memory for the itemName pointer
    item.itemName = (char *)malloc(50 * sizeof(char));

    // Pass the Item pointer to readItem
    readItem(itemPtr);

    // Pass the Item pointer to printItem
    printItem(itemPtr);

    // Free the allocated memory for itemName
    free(item.itemName);

    return 0;
}
```

## **Explanation**

* The `Item` structure is defined with the necessary members.
* The `readItem` function allocates memory for `itemName` and reads user input.
* The `printItem` function displays the contents of the structure.
* In the `main` function, an `Item` structure and a pointer to `Item` are declared.
* Memory is allocated for the `itemName` pointer.
* The `Item` pointer is passed to both the `readItem` and `printItem` functions.
* Finally, the allocated memory for `itemName` is freed.