explanation for this symbol in linked list

Question

guys what's the meaning of -> in linked list?? explain with example please I've searched online and none of the site tells what's this thing and just go straight to coding

example

start=start->next; // (a)
start->prev = NULL; // (b)

is the meaning of

(a) moving start to next node and then assign the next node to start??

(b) idk what it means ,i need explanation thanks

possible duplicate of [Arrow operator (->) usage in C](http://stackoverflow.com/questions/2575048/arrow-operator-usage-in-c) — , Jul 27 '13 at 11:25
Did you see : http://stackoverflow.com/questions/15441745/explanation-of-code-linked-list-c/15442045#15442045 ? — P0W, Jul 27 '13 at 11:27

score 1 · Answer 1 · answered Jul 27 '13 at 11:39

The -> symbol is an operator to select an element from a data structure pointed to by a pointer. So suppose you have a pointer defined as mystruct *p and it points to a mystruct instantiation. Suppose also that mystruct declares a variable i of, say, type int. Then the following notations are equivalent:

(*p).i = 2;

or

p->i = 2;

P0W · Accepted Answer · 2013-07-27T11:57:43.223

0

So, no coding just plain small explanation :-

-> is structure dereference operator

After execution of above statements

a) start pointer will points to the direct next node of itself.

b) start's previous pointer will be assigned to NULL (indicating end of list)

A Doubly linked list, as in your question, is represented as:

enter image description here

Start Pointer is start i.e. start/head of node.

Null is NULL indicates end of list in both the direction.

next pointer signifies next

prev pointer signifies prev

edited Jul 27 '13 at 11:57

answered Jul 27 '13 at 11:40

P0W

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how do we know when to put the equal sign?? ;et – user2421843 Jul 27 '13 at 11:42
let's say start=start->next ,when do we write it as start->next=start?? – user2421843 Jul 27 '13 at 11:43
@user2421843 I'd suggest, first you go through a pictorial representation of linked list, and then you can answer your own questions. – P0W Jul 27 '13 at 11:46

score -2 · Answer 3 · answered Jul 27 '13 at 11:28

-2

That means delete the start node from a double-side list.

And -> is an operator .

answered Jul 27 '13 at 11:28

Lidong Guo

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can you explain how to use them?? – user2421843 Jul 27 '13 at 11:36
This does *not* "delete" anything. It sets a pointer to NULL, that's all. – Jongware Jul 27 '13 at 11:37
jongware, can you explain how to use the operator?? – user2421843 Jul 27 '13 at 11:39
If you do not understand the answers already given: no I can't. – Jongware Jul 27 '13 at 11:46
@Jongware The first node data lost ,if there is no pointer point it ,same as delete. – Lidong Guo Jul 27 '13 at 12:00
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You loose the capability to address it from within the program, but the memory will still be marked "in use". Not the same. – Jongware Jul 27 '13 at 12:05
@Jongware we don't konw the memory is in heap or stack.if it is not come from heap , it will be free auto ,right? And yeah, I didn't articulate .Sorry for that. – Lidong Guo Jul 27 '13 at 12:50

explanation for this symbol in linked list

3 Answers3