:reverse [%1 - string to reverse ; %2 - if defined will store the result in variable with same name]

@echo off

setlocal disableDelayedExpansion

set "str=%~1"

set LF=^

rem ** Two empty lines are required

set ^"\n=^^^%LF%%LF%^%LF%%LF%^^"

set $strLen=for /L %%n in (1 1 2) do if %%n==2 (%\n%

for /F "tokens=1,2 delims=, " %%1 in ("!argv!") do (%\n%

set "str=A!%%~2!"%\n%

set "len=0"%\n%

for /l %%A in (12,-1,0) do (%\n%

set /a "len|=1<<%%A"%\n%

for %%B in (!len!) do if "!str:~%%B,1!"=="" set /a "len&=~1<<%%A"%\n%

)%\n%

for %%v in (!len!) do endlocal^&if "%%~b" neq "" (set "%%~1=%%v") else echo %%v%\n%

) %\n%

) ELSE setlocal enableDelayedExpansion ^& set argv=,

%$strLen% len,str

setlocal enableDelayedExpansion

set /a half=len/2

set "res=!str:~%half%,-%half%!"

for /L %%C in (%half%,-1,0) do (

set /a len=%len%-1-%%C

if %%C neq %half% (

for %%c in (!len!) do (

set "res=!str:~%%c,1!!res!!str:~%%C,1!"

)

)

)

endlocal & endlocal & if "%~2" NEQ "" (set %~2=%res%) else echo %res%