reto nº 10 solucion

@Echo OFF
Title reto nº 10 solucion

:: Caesar encryptor v0.1
:: By Elektro H@cker
:: Foro.elhacker.net

Setlocal enabledelayedexpansion
Set "Charlist= abcdefghijklmnopqrstuwxyzzyxwutsrqponmlkjihgfedcbaABCDEFGHIJKLMNOPQRSTUWXYZZYXWUTSRQPONMLKJIHGFEDCBA01234567899876543210"

:Choose
Set Word=
Cls
Echo+
Echo 1. Encriptar    | MORE
Echo 2. Desencriptar | MORE
Set /P choice=^>
If "%CHOICE%"=="1" (Goto :Encriptar)
If "%CHOICE%"=="2" (Goto :Desencriptar)
Goto :Choose


:Encriptar

:Menu
Cls
Echo Define el SHIFT para la encriptacion (Del 1 al 9) | MORE
Set /P Shifted=^>
Echo %Shifted% | FINDSTR "[1-9]" 1>NUL
If %Errorlevel% EQU 1 (Goto :Menu)
Echo+
Echo Ahora escribe algo para encriptar!! | MORE
Set /P Input=^>
Set /A Next_char_input=0

:Loop
Set "Char=!Input:~%Next_char_input%,1!"
If "%CHAR%" EQU " " (
    Set "Word=!Word! "
    Set /A Next_char_input+=1
    Goto :Loop
)
If not defined char (goto :FIN)
Set /A Next_Charlist+=1
If "%CHAR%" EQU "!Charlist:~%Next_Charlist%,1!" (
    Set /A Next_Charlist+=%Shifted%
    call :Caesarize
    Set /A Next_Charlist=0
    Set /A Next_char_input+=1
    Goto :Loop
) ELSE (Goto :Loop)

:Caesarize
Set "Word=!Word!!Charlist:~%Next_Charlist%,1!"
Goto :EOF

:FIN
Set "Word=!Word!+%SHIFTED%"
Echo+
Echo Su texto encriptado: | MORE
Echo:^> !WORD!
Pause >Nul
Goto :Choose

:Desencriptar

:Menu
Cls
Echo+
Echo Escribe la frase encriptada!! | MORE
Set /P Input=^>
Set /A Next_char_input=0
Set /A Shifted=%Input:~-1%
Set "Input=%Input:~0,-2%"

:Loop_decript
Set "Char=!Input:~%Next_char_input%,1!"
If "%CHAR%" EQU " " (
    Set "Word=!Word! "
    Set /A Next_char_input+=1
    Goto :Loop_decript
)
If not defined char (goto :FIN)
Set /A Next_Charlist+=1
If "%CHAR%" EQU "!Charlist:~%Next_Charlist%,1!" (
    Set /A Next_Charlist-=%Shifted%
    call :Caesarize
    Set /A Next_Charlist=0
    Set /A Next_char_input+=1
    Goto :Loop_decript
) ELSE (Goto :Loop_decript)

:FIN
Set "Word=!Word!+%SHIFTED%"
Echo+
Echo Su texto desencriptado: | MORE
Echo:^> !WORD:~0,-2!
Pause >Nul
Goto :Choose