4 replies to this topic

[fantanoice]

Edit: Nevermind this folks. Turns out the function was actually provided in a source file. My bad...?

Right, so I'm a little confused at how to go about this. O.o (It's probably really simple...)

I've got three struct typedefs, 'Node', 'List' and 'Stack'. These are their contents:

typedef struct Node 
{
    void *data;         /* Pointer to data stored in node */
    struct Node *next; /* pointer to next node in list */
} Node;


typedef struct
{
    Node *head; /* First element in list */
    Node *tail; /* last element in list */
    Node *iterator; /* Used to iterate through list */
    int size;   /* number of elements currently in list */
} List;


typedef struct
{
    List *dataList; /* Stack data is contained in a linked list */   
} Stack;

I already have a push and pop function for the stack which seem to be compiling properly, so let's not worry about that.

I need a function that can count all the elements in the stack and return them in an int. I'm unsure about how to go about this in a logical manner and I can't seem to find any kind of example solution. I'm guessing it would involve something like Stack stackVariable->dataList->size, but I could be compeltely wrong.


Anybody want to give a stab at the logic? D:


----
Edit: I may have worked it out. Does this look right?

int stk_size(Stack *stkPtr)
{
	
	while(stkPtr->dataList != NULL)
		{
			stkPtr->dataList->size = stkPtr->dataList->size + 1;
		}
		
	return stkPtr->dataList->size;
}

Edited by fantanoice, 05 November 2009 - 05:07 AM.

[Guest]

I think you could just use sizeof()
Something like this might work:

size=sizeof(stkPtr->dataList);

[fantanoice]

I don't need to know the size in 'memory', I need to know 'how many', if that makes sense. ;)

[SolidState]

You could increase and decrease the count variable everytime you call your push and pop functions.

Edited by SolidState, 05 November 2009 - 02:23 AM.
Thought better

[fantanoice]

SolidState said:

You could increase and decrease the count variable everytime you call your push and pop functions.

That could work, though I have specific instructions to make a function that will count the elements in the stack. Also, the stack needs to be able to clear at any moment in time, meaning that I would need to assign 0 to a variable every time that happened. It probably isn't the most efficient way to go about things.

But thanks for the input guys.