Having issues with pointers - c

Question

I'm fairly new to programming and i'm having problem with pointers. My code below works with the exception for that my counts doesn't follow with my article number when i sort it. I probably need pointers to get this working but I don't know how.
Can anyone help me?
void printMenu(void)
{
printf("\nMENU:\n");
printf("(D)isplay the menu\n");
printf("(G)enerate inventory\n");
printf("(P)rint inventory\n");
printf("(L)inear search article\n");
printf("(B)inary search article\n");
printf("(I)nsertion sort inventory\n");
printf("B(u)bble sort inventory\n");
printf("(M)erge sort inventory\n");
printf("(Q)uit program\n");
}
void generateInventory(article inventory[], int noOfArticles,
int minArticleNumber, int maxArticleNumber, int maxNoOfArticles)
{
int i, j;
int idCount[] =
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, };
for (i = 0; i < noOfArticles; i++)
{
inventory[i].id = rand() % (maxArticleNumber - minArticleNumber + 1) +
minArticleNumber;
idCount[inventory[i].id - 1] = idCount[inventory[i].id - 1] + 1;
for (j = 0; j <= i; ++j)
{
if (idCount[inventory[i].id - 1] > 1)
{
inventory[i].id = rand() % (maxArticleNumber + minArticleNumber);
}
}
inventory[i].counts = rand() % maxNoOfArticles;
}
}
void printInventory(const article inventory[], int noOfArticles)
{
int i;
printf("\nINVENTORY\n");
printf("%7s %8s\n", "Article", "Count");
for (i = 0; i < noOfArticles; i++)
{
printf("%7d %8d\n", inventory[i].id, inventory[i].counts);
}
}
int getArticleId()
{
int id;
printf("\nGive article id: ");
scanf("%d", &id);
return id;
}
void printSearchResult(const article inventory[], int index)
{
if (index == -1)
{
printf("\nArticle not found\n");
}
else
{
printf("\nArticle id: %d\n", inventory[index].id);
printf("Article counts: %d\n", inventory[index].counts);
}
}
int linearSearchInventory(const article inventory[], int noOfArticles, int id)
{
int i = 0;
int index = -1;
while (index == -1 && i < noOfArticles)
{
if (id == inventory[i].id)
{
index = i;
}
i++;
}
}
int binarySearchInventory(const article inventory[], int noOfArticles, int id)
{
int index = -1;
int left = 0;
int right = noOfArticles - 1;
int middle;
while (index == -1 && left <= right)
{
middle = (left + right) / 2;
if (id == inventory[middle].id)
{
index = middle;
}
else if (id < inventory[middle].id)
{
right = middle - 1;
}
else
{
left = middle + 1;
}
}
return index;
}
void insertionSortInventory(article inventory[], int noOfArticles)
{
int i, j;
int next;
for (i = 1; i < noOfArticles; i++)
{
next = inventory[i].id;
j = i - 1;
while (j >= 0 && next < inventory[j].id)
{
inventory[j + 1].id = inventory[j].id;
j = j - 1;
}
inventory[j + 1].id = next;
}
}
void bubbleSortInventory(article inventory[], int noOfArticles)
{
int c, d, t;
for (c = 0; c < (noOfArticles - 1); c++)
{
for (d = 0; d < noOfArticles - c - 1; d++)
{
if (inventory[d].id > inventory[d + 1].id)
{
t = inventory[d].id;
inventory[d].id = inventory[d + 1].id;
inventory[d + 1].id = t;
}
}
}
}
void mergeSortInventory(article inventory[], int noOfArticles)
{
int temp[noOfArticles / 2];
int nLeft, nRight;
int i, iLeft, iRight;
if (noOfArticles > 1)
{
nLeft = noOfArticles / 2;
nRight = (int) ceil((double) noOfArticles / 2);
mergeSortInventory(inventory, nLeft);
mergeSortInventory(&inventory[noOfArticles / 2], nRight);
for (i = 0; i < nLeft; i++)
{
temp[i] = inventory[i].id;
}
i = 0;
iLeft = 0;
iRight = 0;
while (iLeft < nLeft && iRight < nRight)
{
if (temp[iLeft] < inventory[noOfArticles / 2 + iRight].id)
{
inventory[i].id = temp[iLeft];
iLeft = iLeft + 1;
}
else
{
inventory[i].id = inventory[noOfArticles / 2 + iRight].id;
iRight = iRight + 1;
}
i = i + 1;
}
while (iLeft < nLeft)
{
inventory[i].id = temp[iLeft];
i = i + 1;
iLeft = iLeft + 1;
}
}
}

Answer 1

If I'm correct in what you're asking, you want to keep the idCount array relational to the inventory array. I assume, since you're using article as a type that you've either typedef'd a variable to be an article, which would be pointless, or more likely you've built a struct of type article, then made an array of those structs, and called the array inventory.
If this is the case, then the most likely method of keeping them relational is to just include the count in the article struct.
There are methods of making the arrays relational without doing that, but they're pointless, because a simple four-line struct would do the trick, even if that struct was a wrapper around a different struct, or a header for another struct.

Answer 2

When sorting your records, you only assign the id member of your struct:
inventory[foo].id = inventory[bar].id;
You should assign the complete struct:
inventory[foo] = inventory[bar];
Just remember that temporaries must be of type article an not int so they allso can be assigne a complete struct and not only an id value