Linked List

I am currently learning linked list and our proff gave us this code but I can't seem to compile it, what's the problem here?

Code:

---

#include<stdio.h>
#include<stdlib.h>
#include<string.h>

struct node
{
      int x;
      struct node *next;
      };
     
      int main()
      {
          struct node *root;
          struct node *conductor;
          conductor=root;
          root = malloc(sizeof(struct node));
          root->next=0;
          root->x=5;
     
          while(conductor->next!=0);
          {
              printf("%d",conductor->x);
              conductor=conductor->next;
                                     
                                      }

          system("pause");
          }

---

I can't seem to print the value of x :| why is it like that?


(EDIT Done with the tagging :) )

Read the intro threads - especially one that should be read BEFORE posting code.

Specifically, code tags.

Bump

Bump

Quote:

---

Originally Posted by kyel_dai92

I am currently learning linked list and our proff gave us this code but I can't seem to compile it, what's the problem here?

Code:

---

#include<stdio.h>
#include<stdlib.h>
#include<string.h>

struct node
{
      int x;
      struct node *next;
      };
     
      int main()
      {
          struct node *root;
          struct node *conductor;
          conductor=root;
          root = malloc(sizeof(struct node));
          root->next=0;
          root->x=5;
     
          while(conductor->next!=0);
          {
              printf("%d",conductor->x);
              conductor=conductor->next;
                                     
                                      }

          system("pause");
          }

---

I can't seem to print the value of x :| why is it like that?


(EDIT Done with the tagging :) )

---

Take a close look at the first couple of pointers before malloc()... conductor=root ... what is the value of root at that point?

If this is unmodified code from your instructor, you need to ask him if the bugs in it were deliberate...

what if I want to add another block? or node?

Quote:

---

Originally Posted by kyel_dai92

what if I want to add another block? or node?

---

Well, first you need to fix the bugs in what you've got.

Quote:

---

Originally Posted by CommonTater

Well, first you need to fix the bugs in what you've got.

---

I've fixed it here it is

Code:

---

#include<stdio.h>
#include<stdlib.h>
#include<string.h>

struct node
{
      int x;
      struct node *next;
      };
     
      int main()
      {
          struct node *root;
          struct node *conductor;
          root = malloc(sizeof(struct node));
          conductor=root;
          root->next=0;
          root->x=5;
     
          while(conductor->next!=NULL);
          {
              printf("%d",conductor->x);
              conductor=conductor->next;
                                     
                                      }
         
          system("pause");
          }

---

now how to add anotehr value and block? so that It will print 2 then (the value i inserted )

I take it you're on like day 1 of this part of your course... (which is fine)

Basically you need to create a new struct in memory and get a pointer to it.
Then you need to insert whatever data
Finally you need to add it to the end of your list by modifying the next pointer in your previous last record.

Quote:

---

Originally Posted by CommonTater

I take it you're on like day 1 of this part of your course... (which is fine)

Basically you need to create a new struct in memory and get a pointer to it.
Then you need to insert whatever data
Finally you need to add it to the end of your list by modifying the next pointer in your previous last record.

---

How am I going to do it? my knowledge about linked list is only 10% or even lower how do i do that? I am not gonna modify, I am just gonna add, they are gonna show an output of 5 then 2.

In a linked list each record provides you with a pointer to the next record.

1.next -> 2.next -> 3

So if you want to add #4 you you have to make #3 point to the new entry...

1.nest -> 2.next -> 3.next -> 4

That means modifying the "next" pointer in your last record to point to the new one

I'd suggest you give this a read...
Cprogramming.com Tutorial: Linked Lists

so it'll be like this?

Code:

---




struct node *root;
          struct node *conductor;
          conductor=root;
          root = malloc(sizeof(struct node));
          root->next=0;
          root->x=5;
root->next-next=malloc(sizeof(struct node));
root->x=4;

---

like this?

It's still wrong! You've ignored CommonTater's question:

Quote:

---

Take a close look at the first couple of pointers before malloc()... conductor=root ... what is the value of root at that point?

---

which is extremely important. Don't put the cart before the horse looking to add stuff to what's currently quite broken.

There are a bazillion tutorials and explanations of linked lists on the net. Surely you can Google some up and try to get a better understanding of them?

Quote:

---

Originally Posted by rags_to_riches

It's still wrong! You've ignored CommonTater's question:



which is extremely important. Don't put the cart before the horse looking to add stuff to what's currently quite broken.

There are a bazillion tutorials and explanations of linked lists on the net. Surely you can Google some up and try to get a better understanding of them?

---

well I didn't ignored, I actually read it and used it for my code

Bump

Quote:

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Originally Posted by kyel_dai92

Bump

---

Don't just type "bump". If you have a question, ask a question, and if you want code looked at, post it in code tags. Otherwise, let your thread die.


Quzah.

my codes are inside the codetags

if you could re-read I still have some questions and the my codes are inside the code tags

Your question was already answered. Find the end of your list, and make that node's next point at whatever new node you allocate.

If you actually expect people to help you, when someone says "ask a specific question", they don't want to hear "go back and read the whole thread". All we get from this is that you are too lazy to ask for help the right way. If you are too lazy to ask a question, why should I have to go out of my way to try to answer to the question you are too lazy to ask?


Quzah.

Quote:

---

Originally Posted by kyel_dai92

Bump

---

Tutorial Here

Quote:

---

Originally Posted by CommonTater

Tutorial Here

---

Sorry D: I am really just confuse on my code

Yeah and we've already told you what to do, and I've pointed you at a complete linked list tutorial. I'm done here, you don't listen to anyone.


Quzah.

Quote:

---

Originally Posted by kyel_dai92

Sorry D: I am really just confuse on my code

---

Hey it's code... and just practice at that.
Set it aside, do something else for a while.
This is nothing to panic over.

On the off chance it's homework...
"Excuse me Teach? I need a better explaination about linked lists..."
Really...

Nope, it's not a homework,I really just want to figure it out , or the solution to do it

Quote:

---

Originally Posted by kyel_dai92

I really just want to figure it out ,

---

Really? Me mentioning the complete tutorial on linked lists three times now didn't clue you in? I even provided a link to it.

Quote:

---

Originally Posted by kyel_dai92

or the solution to do it

---

Yeah, that's what I thought. "Do it for me!"


Quzah.

where is it then?

Quote:

---

Originally Posted by kyel_dai92

where is it then?

---

You'd know if you didn't have three threads on the same topic, oh, and if you actually read what people have been typing to you.


Quzah.

is it this?

Cprogramming.com Tutorial: Linked Lists

Quote:

---

Originally Posted by kyel_dai92

Nope, it's not a homework,I really just want to figure it out , or the solution to do it

---

Ok... here's enough to give you some sense of direction....

Code:

---


// find last item
struct item *FindLast(struct item *root)
  { struct item *temp = root;
    while (temp->next != Null)
          temp = temp->next;
    return temp; }

// add new item
struct item *AddNewItem(struct item *root)
  {  struct item *last = FindLast(root);
      // and here comes the new item
    last->next = malloc(sizeof (item)); 
    return last->next; }


int main (void)
  { struct item *root = NULL;
    struct item *new  = AddNewItem( root);

    return 0; }

---

1) Whatever you create here you have to free. So before exiting you need to unwind the list.
2) This is deliberately not scoop and poop code... you're going to have to rewrite it...
3) In future... try a little patience and try asking without demanding.

You keep using dot operators when you should be using the arrow operator. If that's intentional, it's only going to confuse our impatient friend here.


Quzah.

how come there's a struct item *findlast, so that structure is a pointer? and you mean free it, I'll make it equal to NULL , am I getting it right?

Quote:

---

Originally Posted by kyel_dai92

how come there's a struct item *findlast, so that structure is a pointer? and you mean free it, I'll make it equal to NULL , am I getting it right?

---

FindLast from my example is a FUNCTION that returns a pointer to the last item on your list.

No, freeing something does not set it to null. It simply allows the memory used to be returned to the pool. If you want a pointer to equal NULL you have to set it to NULL yourself... as in: ptr = NULL;... it's a two step operation.

Seriously... if these fundimental operations are unclear to you, it's time to go back to the books and do a little more study. You are never going to understand linked lists if you do not understand even the most basic stuff like dynamic memory allocation and release and pointers.

I understand these but about the freeing the memory our professor never teached us that , I really don't know why . we lately discussed about linked list. then as usual I want to study it as always. but then again I am getting confused. but Pointers I do get them .

how can I free a it? is there a code or function I will use?

Quote:

---

Originally Posted by kyel_dai92

I understand these but about the freeing the memory our professor never teached us that , I really don't know why . we lately discussed about linked list. then as usual I want to study it as always. but then again I am getting confused. but Pointers I do get them .

how can I free a it? is there a code or function I will use?

---

Professor??? And he didn't teach about free() when discussing malloc()?
Believe me if you don't understand malloc() and free() you don't understand pointers.

Is this guy even a programmer?

Read this.... Chapter 11: Memory Allocation

thanks for the link, I needed that, and there's function? free()? wow cool? I need to use a malloc after that if Idon't want to use it anymore i'll free it? am I getting it right?

and where do you get this nice references? I was googling a lot but I didn't find that, and could also give ma e reference in linked list with functions?

Quote:

---

Originally Posted by kyel_dai92

thanks for the link, I needed that, and there's function? free()? wow cool? I need to use a malloc after that if Idon't want to use it anymore i'll free it? am I getting it right?

and where do you get this nice references? I was googling a lot but I didn't find that, and could also give ma e reference in linked list with functions?

---

A programmer's most important skill is to know how to look stuff up when he needs to know it...

I don't know what IDE/Compiler you are using but most have library and operating documentation available. You need to gather this documentation and have it at your disposal. Moreover you need to know how to find stuff online when needed.

For example the reference I gave you for malloc() and free() was the result of a simple Google search for "C dynamic memory"... which anyone could have done.

You need to cultivate these skills.

Usually when I search, I typed C programming malloc

to stay in topic, I found out what's wrong with my code, they are not linked together right? and they should start out null? right? and I should use the free() function? am I right?so that I can able to print 2 5 8 . am I getting it?

my compiler is bloodshed dev c++

Quote:

---

Originally Posted by kyel_dai92

Usually when I search, I typed C programming malloc

to stay in topic, I found out what's wrong with my code, they are not linked together right? and they should start out null? right? and I should use the free() function? am I right?so that I can able to print 2 5 8 . am I getting it?

my compiler is bloodshed dev c++

---

That's right... and since they are not linked one to the next, you are leaking memory like crazy. (another issue with malloc() and free())

With a new list only your root pointer... the one that points to the first record should be NULL. The others won't even exist at that point.

When you add to the list you make the pointer in the previous record point to the new record as I've shown you twice now and you set the pointer in the new record to NULL.

You don't free() anything until you are done with the entire list... and then you free all of it starting at the end, working back to the root.

Quote:

---

Originally Posted by CommonTater

That's right... and since they are not linked one to the next, you are leaking memory like crazy. (another issue with malloc() and free())

With a new list only your root pointer... the one that points to the first record should be NULL. The others won't even exist at that point.

When you add to the list you make the pointer in the previous record point to the new record as I've shown you twice now and you set the pointer in the new record to NULL.

You don't free() anything until you are done with the entire list... and then you free all of it starting at the end, working back to the root.

---

soo I am going to do this struct node *root ; root = NULL? is that how I start the 1st list as null?

Quote:

---

Originally Posted by kyel_dai92

soo I am going to do this struct node *root ; root = NULL? is that how I start the 1st list as null?

---

Yes. Just like the tutorials showed you...

after that How do I release it? free()? what code inside free? examples please?

Why don't you wait until your professor covered them?
Have you read the link CT had given???

I have read it, I am just getting confused with some of its examples

No, our professor won't cover them. I guess he want's us to google or something

Okay, i try to share something about linked list. Those who know about it, it's great and those who don't know, it's good for them.. :-)
Actually i start with the base. What is a linked list?
All the lists(data) that are linked to eachother, arises the concept of linked list. Hope that it's too simple to understand now that what's a linked list..

Implementation:
Simple linked list has three important things in it.
1. Data part.
2. Left pointer.
3. Right Pointer.

1. Data Part:
In the data part you can put any kind of data, depends upon the requirements of the problem.
2. Left Pointer:
If you know the concept of pointers, simply, to keep track of immediate left part of your linked list.
3. Right Pointer:
If you know the concept of pointers, simply, to keep track of immediate right part of your linked list.

Now, you've seen that how it works.
Now forexample, i say you to develop a program that will store 1 to 10 integers using linked list?
What you simply have to do is, inside the loop, everytime create a new linked list, assign to the data part, and point the previously created linked list's right pointer to the newly created linked list.

Simply, you've to know about the concepts of pointers. Once you understood, try using your own logics to play with the toughest scenarios ever.

Exercise: Implement stack (using linked list_, queue (using linked list_, one way linked list, two way linked list, circular linked list.


NOTE: This is not the all information that is required to know whole about linked lists. There are alot of things you have to consider but to initially start, you can just follow these instructions. If you need any explaination, you can comment here.

Thanks...

Quote:

---

Originally Posted by kyel_dai92

I have read it, I am just getting confused with some of its examples

No, our professor won't cover them. I guess he want's us to google or something

---

Then your professor is an idiot and you should complain to the school.

It is HIS job to teach you programming in C ... not ours.

Quote:

---

Originally Posted by CommonTater

Then your professor is an idiot and you should complain to the school.

It is HIS job to teach you programming in C ... not ours.

---

I actually did . but he's giving us projects and lessons. and I want to know C so I am also kinda self studying . but he's not even giving us clues or such. and it ticks me off. sorry if I am becoming a pain here in the forum xD

Quote:

---

Originally Posted by kyel_dai92

I actually did . but he's giving us projects and lessons. and I want to know C so I am also kinda self studying . but he's not even giving us clues or such. and it ticks me off. sorry if I am becoming a pain here in the forum xD

---

Go over the man's head! Talk to your principle or dean... Tell him straight out that your proff isn't doing anything but handing you assignments... Tell him you want to actually LEARN C not just pass the course...

In the mean time... sit down with your textbooks (hopefully they aren't too badly out of date) and go through them, do all the examples and assignments, in order... spend the time to actually learn how these things work. As I'm sure you're finding out, simply diving into something way ahead of your understanding is just going to confuse and frustrate.

Really... if you are sincerely interested in learning C... this is not the place to do it. Yes we'll help with specific questions and often we help debug code but none of us here is a teacher and even if we were, this is not how you learn programming.

Climb into the books... work it through chapter by chapter... you'll be glad you did.
Talk to your dean or priniciple... Make it clear you expect to actually learn C in the C course...

I've read different chapters on my reference , and I kinda getting an idea about linked list now this what I made

Code:

---


#include<stdio.h>
#include<stdlib.h>

struct node
{
      int x;
      struct node *next;     
      };
     
struct node *InitializeList(void)
{
      return NULL;
      }
     
struct node *addNode(struct node *root, int y)
{

      root = malloc(sizeof(struct node));
      root->x=y;
      root->next= NULL;
     
     
      return root;
     
     
     
      }
     
      void display(struct node *root)
      {
          struct node *conductor;
          conductor = root;
         
          while(conductor->next!=NULL)
          {
                                printf("%d",conductor->x);
                                conductor=conductor->next;
                                }
          }
     
 int main()
 {
    struct node *root;
    root = InitializeList();
    root = addNode(root,5);
      root = addNode(root,3);
    display(root);
 
   
   
    system("pause");
    }

---

I really don't know if I have improved , but I want you guys to check out the code I did. the only problem in there is that It didn't print the values of 5 and 3

Does this program give any errors? If yes post them here....
It looks like it'll fill the stack with the list of errors :-)

Quote:

---

Originally Posted by Mr.777

Does this program give any errors? If yes post them here....
It looks like it'll fill the stack with the list of errors :-)

---

why is that, I even traced that on a paper of how each works, but I still keep on wondering why it doesn't print 5 and 2 though

Your addNode doesn't work right. You should be adding something like this:

Code:

---

add( n )
    p = malloc
    p->next = n
    return n

---

Otherwise, you are just throwing away 'root' when you are inside the function, by immediately trying to malloc over top of whatever you are passing (the way you are doing it now).

Quzah.

Quote:

---

Originally Posted by quzah

Your addNode doesn't work right. You should be adding something like this:

Code:

---

add( n )
    p = malloc
    p->next = n
    return n

---

Otherwise, you are just throwing away 'root' when you are inside the function, by immediately trying to malloc over top of whatever you are passing (the way you are doing it now).

Quzah.

---

i see , a question I might ask, is my function for display correct? and aobut that

p=malloc
p->next=n; should I only add that? or tweak it more?

this time I didn't use malloc, am I doing it right?

Code:

---

struct node *addNode(struct node *root, int y)
{
      struct node *pTemp;
      root = pTemp;
      pTemp->x=y;
      pTemp->next= NULL;
     
     
      return root;
      }

---

No. You can't make a new node without allocating space for it. Go read that linked list tutorial over and over until you understand it.


Quzah.

Quote:

---

Originally Posted by quzah

No. You can't make a new node without allocating space for it. Go read that linked list tutorial over and over until you understand it.


Quzah.

---

alright, other than that, is my display function wrong?

It's wrong because if you pass it a single node, it won't display its contents. You should be checking to see if it is null, not if ->next is null.


Quzah.

Quote:

---

Originally Posted by quzah

It's wrong because if you pass it a single node, it won't display its contents. You should be checking to see if it is null, not if ->next is null.


Quzah.

---

okay, I am going to fix my addNode function first and I'll come back here if there are any problems, well how do I pass the other nodes? in my code?

(Linked list is starting to ........ me off, is this even usefull when I transfer to C to java?)

here's my new one

Code:

---

struct node *addNode(struct node *root, int y)
{

      root->x=y;
      root->next->next=malloc(sizeof(struct node));
     
     
      return root;

---

my thought on this is that I Initialize the list as NULL , so I am thinking if I am going to add new node I should do this, am It getting right?

Quote:

---

is this even usefull when I transfer to C to java?)

---

If you are talking about concept, i would say yes
and if about code, NO!!!

Quote:

---

Originally Posted by Mr.777

If you are talking about concept, i would say yes
and if about code, NO!!!

---

Not the code, I was talking about the concept

Then YES!!!

Now let's stay on topic xD

Sample but it will only be a pseudocode.

Code:

---

Node * addNode(parameters a, b...)
{
if(root!=NULL)
{
create node.
assign value
assign it's next to NULL.
}
else
{
create node.
take a temporay pointer.
temp=root;
while(temp->Next!=NULL)
{
temp=temp->next;
}
temp->next=new node that you have created.
temp->next=NULL;
}

---

Quote:

---

Originally Posted by Mr.777

Sample but it will only be a pseudocode.

Code:

---

temp->next=new node that you have created.
temp->next=NULL;

---

---

You just lost your new node with that last line. We've been trying to get him to understand linked lists for days now. You aren't doing us any favors.

Quzah.

Quote:

---

Originally Posted by quzah

You just lost your new node with that last line. We've been trying to get him to understand linked lists for days now. You aren't doing us any favors.

Quzah.

---

why is that?

Here's my new code, it adds a new node, the only problem is that how should I add the value of 5 and 3 ?? and the displaying but it looks like everything is going well

Code:

---


#include<stdio.h>
#include<stdlib.h>

struct node
{
      int x;
      struct node *next;     
      };
     
      struct node *New;
      struct node *head;
     
struct node *addNode(struct node *head, int y)
{
      struct node *current;
      current = head;
     
      while(current->next!=NULL)
      {
                                current = current->next;
                                New=malloc(sizeof (struct node));
                                current->next=New;
                                New->next=NULL;
                                }
     
      }
     
      void display(struct node *root)
      {
          struct node *conductor;
          conductor = root;
         
          while(conductor->next==NULL)
          {
                                printf("%d",conductor->x);
                                conductor=conductor->next;
                                }
          }
     
 int main()
 {
   
    head= NULL;
    head = addNode(head,5);
      head = addNode(head,3);
    display(head);   
    system("pause");
    }

---

Look, we've tried helping you. We've shown you a tutorial that hand feeds you everything you ever need to know. I'm done now. You aren't even trying to learn. You just keep throwing code up hoping some of it sticks. Look at this:

Code:

---

struct node *addNode(struct node *head, int y)
{
      struct node *current;
      current = head;
     
      while(current->next!=NULL)
      {
                                current = current->next;
                                New=malloc(sizeof (struct node));
                                current->next=New;
                                New->next=NULL;
                                }
     
      }

---

You are making a new node on every pass of your loop! This time I mean it, I'm done. You have had five threads and we've been working on this for as many days, and you haven't learned anything.


Quzah.

Kyel ...as reluctant as I am to agree with Quzah on *anything* he's speaking the truth.

We've tried giving you examples, suggestions, code snippets, links to tutorials, you name it.
My friend you just don't seem to be getting it and you've about used up everyone's patience in the process.

Really, I just don't think you're programmer material.

Quote:

---

Originally Posted by quzah

You just lost your new node with that last line. We've been trying to get him to understand linked lists for days now. You aren't doing us any favors.

Quzah.

---

Better try to understand what i mean to do... It's just a temporary pointer that will help his/her code to locate the last node......
And we are not concerned with the temp, instead of inserting a new node... And we didn't loose any of the node as root pointer is pointing to the first node of linked list..

Are you up for the suck???

Kyle, try to understand what you are doing here.....

In AddNode(), your current pointer is null as your head is null.
And you are trying to compare it's next to something....
Do you really thing that if a pointer has null (that means, no node) and you try to compare what's in the next part of the node, having no node... Just think about and you can do this...

after those constructive crictscism I was finally able to do it

Quote:

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Originally Posted by Mr.777

Better try to understand what i mean to do... It's just a temporary pointer that will help his/her code to locate the last node......
And we are not concerned with the temp, instead of inserting a new node... And we didn't loose any of the node as root pointer is pointing to the first node of linked list..

Are you up for the suck???

Kyle, try to understand what you are doing here.....

In AddNode(), your current pointer is null as your head is null.
And you are trying to compare it's next to something....
Do you really thing that if a pointer has null (that means, no node) and you try to compare what's in the next part of the node, having no node... Just think about and you can do this...

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Thank you :) at least someone here is encouraging me but hey I did :) thanks to everyone who helped me all I have to do is remove the node

Now the only thing I need to worry about are removing nodes how do I actually remove a node? do i need to make another function for? it? any suggestions?

Quote:

---

Originally Posted by Mr.777

Better try to understand what i mean to do... It's just a temporary pointer that will help his/her code to locate the last node......
And we are not concerned with the temp, instead of inserting a new node... And we didn't loose any of the node as root pointer is pointing to the first node of linked list..

---

Wrong! You are as bad as he is. Look!

Code:

---

n1 -> n2 -> n3 -> n4;
t = n4; /* point at n4 with a temporary pointer */
t->next = new node;
t->next = NULL; /* you just lost your new node */

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I didn't say you lost the whole list. I said you lost your new node.

Quzah.

Quote:

---

Originally Posted by quzah

Wrong! You are as bad as he is. Look!

Code:

---

n1 -> n2 -> n3 -> n4;
t = n4; /* point at n4 with a temporary pointer */
t->next = new node;
t->next = NULL; /* you just lost your new node */

---

I didn't say you lost the whole list. I said you lost your new node.

Quzah.

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I didn't make a temporary pointer :|

Quote:

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Originally Posted by kyel_dai92

I didn't make a temporary pointer :|

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I wasn't talking to you. Since when did you start actually reading what I posted anyway? That's a rhetorical question, I don't care what your answer is.


Quzah.

Quote:

---

Originally Posted by quzah

I wasn't talking to you. Since when did you start actually reading what I posted anyway? That's a rhetorical question, I don't care what your answer is.


Quzah.

---

Thing is... he's reading but he's not understanding.

Quote:

---

Originally Posted by quzah

Wrong! You are as bad as he is. Look!

Code:

---

n1 -> n2 -> n3 -> n4;
t = n4; /* point at n4 with a temporary pointer */
t->next = new node;
t->next = NULL; /* you just lost your new node */

---

I didn't say you lost the whole list. I said you lost your new node.

Quzah.

---

The ........ i am caring for my new node???
Go get some mental level first quzah, don't keep messing with my posts, dip............
Get the hell outta here of my posts, you can't even understand what i am talking about or what a programmer can do... Don't i find my new node???
You are really lifeless.

quzah, stop posting if you are not going to reply in a appropriate manner in this thread.

Quote:

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Originally Posted by Mr.777

The ........ i am caring for my new node???

---

No you aren't. I just showed you what you did wrong.

I find it hilarious that the two people here that have no idea what to do with pointers and linked lists are running to support each other against the big mean scary guy who has been trying to tell you what you were doing wrong the whole time.


Quzah.

if we are wrong, point it out on the code

@kyel_dai92:

I'm not the best around here with linked lists - generally, I dislike to use them even.

Quzah is someone who is sometimes not the easiest to figure out what he means, and we have certainly had our personal disagreements, but:

-- He knows what he's talking about, in C --

and you've been given some good advice by Tater and Quzah, both.

May I suggest you ignore any personal or petulant posts that have been made, and review the factual code suggestions that these two have made for you?

I'm not making any derogatory remarks about 777, btw. He's been helpful in many posts.

IMO, you need to learn and practice the standard idiom's that every beginner must learn in C, when dealing with a linked list - especially how to "walk" it, from head to end. How to create a new node, and how to delete a node from the list, etc.

It takes practice to work with linked lists, and you should be practicing as you read through your tutorials, and suggestions you receive.

Many times, what Quzah posts, is not the "instant" answer - it's something that you need to ponder a bit, and raise your understanding.

If you write a little function to print out the address (%p format in printf()), and the value of the node of a small linked list, you would understand it quicker.

sorry :(. can we just stay in topic here?

You have it all working except to delete a node from the list?

Yes, it's always a good idea when you can group things by what they do, into functions.

Post up your latest code and let's see what you're stuck on.

SO i've decided to change my code to pass by reference due to my curiosity soo here it is but the problem is it's not working it doesn't print anything again

Code:

---

#include<stdio.h>
#include<stdlib.h>

struct node
{
      int x;
      struct node *next;
      };
     
 void add(struct node **root, int x)
 {
      struct node *conductor;
      if(root==NULL)
      {
          (*root)=malloc(sizeof(struct node));
          (*root)->x=x;
          (*root)->next=NULL ;       
                    }
    else
    {
        conductor = *root;
        while(conductor->next!=NULL)
        {
            conductor = conductor -> next;           
                          }
        conductor->next=malloc(sizeof(struct node));
        conductor->next->x=x;
        conductor->next->next=NULL;
        }
      }     
      void display(struct node *root)
      {
          struct node *conductor;
          conductor=root;
          while(conductor!=NULL)
          {
            printf("%d",conductor->x);
            conductor = conductor ->next;                         
                                }
          }
     
   

int main()
{
    struct node *root;
    root=NULL;
    add(&root,5);
    add(&root,4);
    display(root);
    free(root);
system("pause");   
}

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