15 replies to this topic

[zemzela]

I made a code in assembly 8086. I load matrix (array) in memory with dimension 3x3. but this code works just for this dimension of matrix 3x3. Could someone give me an idea how could i make it to work with dimension m x n? the array is loaded in memory and at the end just print the result, another array. thanks

[Sysop_fb]

Wrong forum,
Could you post your code? Is it all in assembly or is it a mixture and the function you wrote is in assembly?
Multi dimensional arrays as you would consider them in a language such as C where a 3x3 would look like

* * *
* * *
* * *

In memory when it's allocated actually looks like this

* * * * * * * * *

Handling it in assembly you'll basically have to handle the offsets yourself.

Here's a website with a graphic explanation

4.6 Multidimensional Arrays

[RhetoricalRuvim]

Sysop_fb said:

Wrong forum,

zemzela said:

I made a code in assembly 8086.

8086 assembly seems like it would go in the assembly forum.

* * *

As for the question, I would say you'd need to find a way to make the matrix size handling more dynamic, rather than assuming it's 3x3. You would also need to have a way to tell the code the dimensions, m and n, so that it can know the size. I don't think you can use the data size for that, unless it's a square matrix, because 3x2 and 2x3 would both have the same storage data size, but different dimensions.

So the next step would probably be writing the formulas and algorithms that you would use to calculate the offsets, and such, like Sysop_fb said, and then you would just need to work on entering the code that executes the algorithms.

[dargueta]

Could you post your code? It'd be a lot easier for us to help you if we could see what you're doing and how you're going about it. Please use the code tags when posting, by the way. Paste your code in, highlight it, and click the # button.

[zemzela]

; multi-segment executable file template.

data segment
  matrix db 1, 2, 3, 4, 5, 6, 7, 8, 9  ; load matrix in memory
    
ends

stack segment
    dw   128  dup(0)
ends

code segment
start:
; set segment registers:
    mov ax, data
    mov ds, ax
    mov es, ax
                      
                      
                
    mov bx, matrix    ;  move matrix to offset bx
    mov ch, 3
    mov cl, 0
    
   
COLUMNAHEAD: 
    
    mov dl, [bx]   ; get the first element of matrix in dl
    add dl, 30h    ; add to show number
    mov ah, 02h
    int 21h       ;  print first number
    inc cl         
    
    cmp cl, ch ; compare if the counter is at the end of column
    
    
    jge ROWAHEAD   ; if greater go to row
    add bx, 3                  ; if not inc offset for 3 
   jmp COLUMNAHEAD
    
   
    
    
    
ROWAHEAD:
    inc cl               ; 1 element of roe
    inc bx             ; inc offset for one place
    mov dl, [bx]  ; get the number in dl
    add dl, 30h   ; convert to number
    mov ah, 02h
    int 21h  ; print the number
   
    cmp cl, 5                         
    je COLUMNAHEAD
    jne ROWAHEAD  
    
    
COLUMNBACK:
    inc cl  
    sub bx, 3
    mov dl, [bx]
    add dl, 30h
    mov ah, 02h
    int 21h 
    cmp cl, 7
    jne  COLUMNBACK 
    je ROWBACK
    
ROWBACK:
   dec bx 
   mov dl, [bx]  
   add dl, 30h
   mov ah, 02h
   int 21h 
   JMP MIDDLE
   
   
MIDDLE:
  add bx, 3
  mov dl, [bx]  
  add dl, 30h
  mov ah, 02h
  int 21h 
   
  JMP END
  
  END:  

this is the code i wrote. it works for the matrix
1, 2, 3,
4, 5, 6,
7, 8, 9 and print 1, 4, 7, 8, 9, 6, 3, 2, 5

Matrix given in memory to print the spiral in opposite direction from clockwise (left column down the right lower range, right up column, a series of upper left, etc. until you get to the environment). This works just for dimension 3x3. this should works for mxn dimension. but i don't know how, any suggestion???

Edited by dargueta, 24 December 2011 - 01:18 PM.

[dargueta]

Dude, please use code tags. It makes your code easier for us to read, especially in C/C++ and such.

Anyway, are you going to get your dimensions from the terminal (i.e. have the user type them in) or are they going to be compile-time equ constants?

[zemzela]

i load my array in memory in the first line of code. i wrote the code with offset which will pass through the array and print just the number with offset given in condition. for example jump 3 numbers ant print the fourth. this works for the matrix 3x3 not for another dimension matrix for ex. 1,2,3,4,5,6,7,8,9,4,5 Thank you for your suggestions.

[dargueta]

You didn't answer my question, which is what I need to help you solve your problem.

[RhetoricalRuvim]

@zemzela: In other words, if m and n are the dimensions of the matrix, how, exactly, do you get the values for them?

Do you input them using a prompt box?:

var m= parseInt (prompt ("Please enter the height of the matrix:")); 

...

Or do you ask for the dimensions via command line?:

int m; 

printf ("Please enter the height of the matrix: \r\n"); 

scanf ("%d", &m); 

...

Or maybe you read the dimensions from a file?:

%define SIZEOF_OFSTRUCT ... 


main: 

enter 0, 0 


sub esp, 8 

sub esp, SIZEOF_OFSTRUCT 

sub esp, 4096 


;; [esp-4] = hFile 

;; [esp-8] = integer () 

;; [esp-(8 + SIZEOF_OFSTRUCT)] = the reopen buffer 

;; [esp-(8 + SIZEOF_OFSTRUCT + 4096)] = read buffer 


push dword 0 

lea eax, [ebp-(8 + SIZEOF_OFSTRUCT)] 

push dword eax 

call .over1 

db "file01.txt", 0 

.over1: 

call [OpenFile] 

mov dword [ebp-4], eax 


push dword 0 

lea eax, [ebp-8] 

push dword eax 

push dword 4096 

lea eax, [ebp-(8 + SIZEOF_OFSTRUCT + 4096)] 

push dword eax 

push dword [ebp-4] 

call [ReadFile] 


push dword [ebp-4] 

call [CloseHandle] 


..... 

Or how does the program know the dimensions of the matrix?



P.S. I didn't test any of the code above.

[dargueta]

Just an FYI, zemzela is using MASM and RhetoricalRuvim is using NASM. Copying and pasting code won't quite work; you'll have to translate the directives like segment and ends.

[zemzela]

via command line.

The text of task is: Matrix given in memory to print the spiral in opposite direction from clockwise (left column down the right lower range, right up column, a series of upper left, etc. until you get to the middle)

The code must work for matrix with 4x3, 3x4, 5x5, etc. If you know help me with code in C++ or C. It is very important if you know, help me.

[RhetoricalRuvim]

I wrote something like this once in JavaScript, but it's for clockwise, not counterclockwise; it's in another thread on CodeCall.


@dargueta: Is it considered doing the OP's homework if I post a link to the other thread that has that JavaScript code?