please help

[royale]

how to convert a string of letters like abc to 123? anyone knows?

[dsouza123]

For this very particular conversion the following code will work,
but more information is needed.

A translation table to show how to convert between the letters and numbers.
Is it in chunks of letters or individual characters, is it a hex string to decimal string ?

Code Select Expand


    .686
    .model flat, stdcall
    option casemap :none
    include \masm32\include\windows.inc
    include \masm32\include\kernel32.inc
    include \masm32\include\user32.inc

    includelib \masm32\lib\kernel32.lib
    includelib \masm32\lib\user32.lib

.data
  szInfo   db "abc",0
  szBTitle db "Before",0
  szATitle db "After ",0

.code
start:
   invoke MessageBox,NULL,ADDR szInfo,ADDR szBTitle,MB_OK

   mov eax, dword ptr szInfo
   sub eax, 303030h
   mov dword ptr szInfo, eax

   invoke MessageBox,NULL,ADDR szInfo,ADDR szATitle,MB_OK

   invoke  ExitProcess, 0
end start


[Vortex]

royale,

Have a look at the Masm32 library reference. It provides a lot of convertion functions. Study the functions to create your own convertion routines.

[MichaelW]

royale,

I'm assuming that this is the same question as in your encoding post. Assuming that the string will contain only the lower-case letters a-z, then the encoding can be done by subtracting 96 from the ASCII character code for each character in the string. For example:
The ASCII character code for 'a' is 97, and 97-96 = 1
The ASCII character code for 'b' is 98, and 98-96 = 2
...