strlen0.3

:strlen0.3  StrVar  [RtnVar]
:: http://ss64.org/viewtopic.php?id=424
  setlocal EnableDelayedExpansion
  set "s=#!%~1!"
  set "len=0"
  for %%A in (2187 729 243 81 27 9 3 1) do (
    set /A mod=2*%%A
    for %%Z in (!mod!) do (
        if "!s:~%%Z,1!" neq "" (
            set /a "len+=%%Z"
            set "s=!s:~%%Z!"

        ) else (
            if "!s:~%%A,1!" neq "" (
                set /a "len+=%%A"
                set "s=!s:~%%A!"
            )
        )
    )
  )
  endlocal & if "%~2" neq "" (set %~2=%len%) else echo **%len%**
exit /b