Linked List in C without malloc

Question

Is it possible to insert an unsigned long into a linked list ordered from smallest to largest without dynamic memory, using malloc or free?

All you need is to write a function that inserts integers in an array in the given order. — Vlad from Moscow, May 08 '15 at 06:30
@VladfromMoscow But that wouldn't make it "a linked list", would it? — unwind, May 08 '15 at 06:34
possible duplicate of [Linked Lists in C without malloc](http://stackoverflow.com/questions/3856317/linked-lists-in-c-without-malloc) — WedaPashi, May 08 '15 at 06:42
@unwind It will be a linked list. The array is simply is an allocator. — Vlad from Moscow, May 08 '15 at 06:44
@WedaPashi You can use different allocators with the same data structure. And an array is one of allocators. See also the answer to the question. — Vlad from Moscow, May 08 '15 at 07:01
@VladfromMoscow Sure, you can use an array to get the storage, but that's not what your original comment sounded like, which is why I questioned it. — unwind, May 08 '15 at 07:07
@VladfromMoscow: Blam! With all due respect to you, (but) Don't be surprised if I take that too personal and offensive. (BTW, its *qualification*, I assume a good programmer is good with keyboards as well) — WedaPashi, May 08 '15 at 07:18

score 4 · Answer 1 · answered May 08 '15 at 06:36

You can pre-allocate a bunch of list entries in the form of an array, then pick entries from that array when you do an insert. This is of course only possible if the array is either global, or at otherwise kept in scope for the duration of the insertion operation.

Something like:

struct integerNode {
  int                value;
  struct integerNode *next;
};

struct integerNode nodes[100]; /* adjust for your number of integers */

The next step would be to use a trivial for loop to link the items in nodes together, forming a linked list of free items. Then write a function that de-links a node from the free list and links it into another list, while inserting the number.

Linked List in C without malloc

1 Answers1