0

I am brand new to this language and my task is to create a program with 3 procedures. One procedure which asks the user for a number, another procedure which finds the factorial of that number, and a final procedure to print the information.

I wrote the first procedure and I'm now up the the hard part, finding the factorial.

I believe I have the correct code for the most part but when trying to pass the procedure with the input from user, I run into errors.

Here is my code (I tried to put as many notes as possible so you can see where my head is at just in case I'm on the wrong track) :

include c:\asmio\asm32.inc
includelib c:\asmio\asm32.lib
includelib c:\asmio\User32.lib 
includelib c:\asmio\Kernel32.lib 

input proto ; 0 parameters
Factorial proto nv: dword ; 1 parameter

; -------------------------------------------------------
.const 
NULL = 0
; -------------------------------------------------------

.data
       nvx dword ?  ;
       ask byte "Enter a number between 1-12: ", NULL
; -------------------------------------------------------
.code 
main proc 
       invoke input ; gets input from user, see procedure below

       mov nvx, eax ; after first procedure, moves given input from user into variable

       invoke Factorial nvx: dword  ; This is where my error is according to compiler

 ret 0 
 main endp 
 ; -------------------------------------------------------
  input proc 
        mov   edx, OFFSET ask  
        call  WriteString        
        call  ReadInt    
ret
input endp
 ; -------------------------------------------------------

    Factorial proc USES ECX EAX EBX nv: dword 
        mov ecx, nv ;start loop counter at value given by user because we need to multiply this many times to find the factorial.

        mov ebx, nv ; hold value of nv as divisor

        inc nv ; This is to account for 0! We increment by one and after the loop divide by nv

        mov eax, nv ; stores the largest number for multiplication


    L1:     
        dec nv ; becomes next largest number
        mul nv ; multiplication 
        mov eax, edx ; stores product into eax for next multiplication
        loop L1

        cdq
        idiv ebx ; divide final product by original number entered for the correct factorial

        ret
        Factorial endp


end main ; End of the entire program
; -------------------------------------------------------

Here is my error log:

[11:20:28] Build started...
[11:20:28] Warning! Errors have occurred in the build:
 Assembling: C:\Users\yp0l0\AppData\Local\Temp\SASM\program.asm
C:\Users\yp0l0\AppData\Local\Temp\SASM\program.asm(30) : error A2206: missing operator in expression
LINK : fatal error LNK1181: cannot open input file "C:\Users\yp0l0\AppData\Local\Temp\SASM\program.o"

Thanks for any help!

Google Z
  • 5
  • 3
  • You're not using `invoke` correctly. See the [documentation](https://learn.microsoft.com/en-us/cpp/assembler/masm/invoke?view=vs-2019). – 1201ProgramAlarm Oct 27 '19 at 16:12
  • @1201ProgramAlarm Thanks so much for the reply! Based on documentation, I believe i'm supposed to put brackets around my parameters but doing do results in an error stating "error A2096: segment, group, or segment register expected" for the same line. Am I on the right track ? – Google Z Oct 27 '19 at 16:28
  • Use `invoke Factorial, nvx`. You need a comma to separate parameters. – 1201ProgramAlarm Oct 27 '19 at 16:30
  • @1201ProgramAlarm ahhh, makes more sense, got thrown off there lol. Thanks a lot! One step closer – Google Z Oct 27 '19 at 16:43

0 Answers0