Ok here we go again, Linked List

[Jbarrera]

Hello all, I have a few questions maybe someone can help me with.
** 1st - while this is not really an kip irvine question....I am limited to his material only. I cannot use any of the fancy stuff in MASM32
**2nd - If my questions sound retarded it's because they are, they say there are no such things as stupid questions....but I think there are, I ask most of them.


I am trying to build a linked list, I have never tried and this is my 1st time.
is there another way to make or simulate a linked list besides doing something like this?

Code Select Expand



ListNode STRUCT
    NodeData DWORD ? ; the node's data
    NextPtr DWORD ? ; pointer to next node
ListNode ENDS



I have a file that I have read into a buffer in my program.
The data file looks like this:

Code Select Expand


Joe     80
Billy    78
Jerry   60
Amy   100


I would like to use the stack and address references to access values indirectly.
I have to sort the data and put it in a linked list in grade order from least to greatest.

The other problem is that I don't know how I would save the name and grade individually.

Thanks for any feedback

[RuiLoureiro]

Hi Jbarrera,
                  you may see this (Linked List Database)

http://masm32.com/board/index.php?topic=3226.msg34406#msg34406

[Jbarrera]

Wow, that is a really nice write-up, it really is. I see that you are not a fan of the Irvine stuff.....me...this is my first-semester taking assembly and That's all I have to work with
you are including in your asm program

\masm32\include\masm32rt.inc     
.686

all I've been using is
Irvine32.inc
for all my programs,

it's not like I can walk up to my professor and tell him, hey why don't you start using the masm32.inc, right?....lol

Your program is a Ferrari, yet I can't even drive.
Don't give me wrong, I read your program, it's really nice, it's just way over my head.

[jj2007]

it's not like I can walk up to my professor and tell him, hey why don't you start using the masm32.inc, right?....lol

That is exactly what you should do :t

Your program is a Ferrari

Don't exaggerate. To put things in proportion:

Masm32rt.inc:	Irvine.inc:

[RuiLoureiro]

Hi JBarrera
    You have records of Name+Grade. So define a ListNode struct for name, for grade and for pointer to next node. Define a buffer - an array (a database) - for N records and format it first. After this you know where to put the next record (Name and Grade). Next you call a procedure to adjust the pointer to the next node ... The database needs to have (at least) a variable that points to the first record and a variable to point where to put the next record.
Think about it.
Good luck  :t

EDIT: Taking your example we may have this:

.data
FirstRecord   dd 3        ; first is record 3
AllocRecord   dd 5       ; put next into record 5

LkdDatabase  dd  4                 ; Record 1   -> next is record 4
                     dd 80                ; grade
                     db "Joe       ",0  ; name
                     ;
                     dd  1                 ; Record 2     -> next is record 1
                     dd 78
                     db "Billy     ",0
                      ;
                     dd  2                  ; Record 3       -> next is record 2
                     dd 60
                     db "Jerry     ",0
                     ;
                     dd 0                    ; Record 4       -> 0=> this is the last
                     dd 100
                     db "Amy       ",0
                     ;
                     dd 6                    ; Record 5        -> next to alloc is record 6
                     dd 0
                     db "          ",0
                     ;
                     ...

In this example we use indexes, not pointers. We may save the variables and the database to a file and we may alloc memory and load it again from file to memory and it works correctly.
When we fill in the record 5 we move the index 6 to the variable AllocRecord. The last value must be 0. If AllocRecord is 0 when we try to alloc a new record it means that the Database is full. FirstRecord must start with 0 which means that there are no records. AllocRecords starts with 1.