An In-Depth Understanding of Memory and Pointers in C/

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Coding Challenge: Modeling Complex Objects and Relationships (2)

Coding Challenge: Modeling Complex Objects and Relationships (2)

Practice everything learned so far by building an application to handle a flower business.

We'll cover the following...

Task 6: Coding challenge

Now we have all the pieces needed to open a TFlowerShop, which we’ll add to the flower shops list using the function from Task 4. We’ll initialize the two flowers using the function from Task 5.

Write a function called openFlowerShop, which will allocate, initialize, and return a pointer to a TFlowerShop structure.

The function header is:

TFlowerShop* openFlowerShop(TFlowerBusiness* flowerBusiness, int continentId, char* name, char* address, int openingYear)
  • flowerBusiness is the current business.
  • continentId is the ID of the continent where we want to open the business.
  • name, address, and openingYear are used to initialize some of the members inside the TFLowerShop.
  • The function must return NULL on failure.
  • It must also make sure to allocate and initialize all the members correctly.
  • After we allocate the flower shop, we must add it to the flower shops list of that continent. You may want to use the function from Task 4, but check its return value and guard against realloc fails.
  • What happens if this shop is the first shop in the continent? In other words, this is the first time our business opens a shop in the new continent. You may want to use the function allocContinent from Task 3.

This task is the most challenging task in the whole project. Make sure to pay special attention to it.

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TFlowerShop* openFlowerShop(TFlowerBusiness* flowerBusiness, int continentId, char* name, char* address, int openingYear)

{

	return NULL;

}

Press the “Show Solution” button to view the solution. The main workflow is as follows:

  • Allocate and fully initialize a flower shop, making use of addFlowersToFlowerShop.
  • Check if we are already present on the continent where we want to open this shop.
    • If not, allocate the continent using allocContinent.
    • If the allocation fails, clean up the shop.
  • Add the flower shop to the list of flower shops using the function addFlowerShopToList.
    • If the addition fails, it may be a realloc fail.
    • Clean up the shop.
    • Clean up the continent only if it’s empty. This scenario can happen if we just allocated it and wanted to add the first shop but failed. Reset all the pointers to NULL so, at a later point, we know that we freed the memory and must reallocate.

Task 7:Demo task

At ...