Thread: Accessing a data element in a function

I cannot for the life of me figure out how to get stuff out of my array that i pass to my function(listSort()). all i want for example is data[0] in my function that i called. i can figure out the rest of what i'm supposed to do if i can do this. any help is greatly appreciated! (this is for a linkedList sort program, so i cant do a simpler array type)

main.c

Code:

[tag]
#include <stdio.h>
#include <time.h>
#include "list.h"

#define ARRAY_SIZE 4


int main() {
	
    double data[] = {9,3,4,2};
    int i;

    listSort(&data);

    for (i = 0; i < ARRAY_SIZE; i++)
       printf("%g\n", data[i]);
}
[/tag]

listSort.c

Code:

[tag]
#include <stdio.h>
#include <assert.h>
#include "list.h"

void listSort (struct linkedList * lst){
	double u;

                u = lst[0]; //<----------------------------here is what i cant figure out. how do i access the data in lst???

	printf("%g\n", n);
[/tag]

i dont know if my .h file matters.... but i'll include it anyways i guess. (i have all these already coded)
list.h

Code:

list.h[tag]
#ifndef _list_
#define _list_

#ifndef Eletype
#define EleType double
#endif



struct dlink{
	EleType value;
	struct dlink * next;
	struct dlink * prev;
};

struct linkedList{
	int size;
	struct dlink * frontSentinel;
	struct dlink * backSentinel;
};

void listSort (struct linkedList * lst);

void LinkedListInit (struct linkedList *q);
void linkedListFree (struct linkedList *q);
void linkedListAddFront (struct linkedList *q, EleType e);
void linkedListAddBack (struct linkedList *q, EleType e);
void linkedListRemoveFront (struct linkedList *q);
void linkedListRemoveBack (struct linkedList *q);
int linkedListIsEmpty(struct linkedList *q);
void _addLink(struct linkedList *q, struct dlink *lnk, EleType e);
void _removeLink(struct linkedList *q, struct dlink *lnk);
EleType linkedListFront (struct linkedList *q);
EleType linkedListBack (struct linkedList *q);

#endif
[/tag]

i've looked at over a dozen tutorials and example code, everything is posted in a single .c file(or .cpp), i need to put these in 2 different ones. thanks for your time!

lst[0] is not an int; it is a linked-list-node kind of a thing. So you would use dots just like everywhere else.

Or, I guess reading it, your function shouldn't take a struct Linkedlist thing, but an array of doubles.

I cannot for the life of me figure out how to get stuff out of my array that i pass to my function

Well, if data is an array, to access the ith element of it, you just need to use "data[i - 1]". But then, that's pretty basic.

I don't know what you are trying to do, but you look a bit lost. You are passing a variable of type double[4] (who gets implicitly cast into a double *) to a function taking a struct linked list *. There should be a bell ringing in your head, if it's not in your compiler.

you are initializing your linked list as if it is an array of ints

do you really want and array of ints?

according to your function prototype lst[0] is a struct - there is no format in printf to print a whole struct

%g format is used to print float numbers in scientific notation so why do you expect to see "9"?