for /r F: %%i in (*) do call :zzz %%~zi
set /a kg=n/1000000000,km=n%%1000000000/1000000,kk=n%%1000000000%%1000000/1000,kb=n%%1000000000%%1000000%%1000
set /a kgm1=km/100,kgm2=km%%100/10
echo %kg%GB%km%MB%kk%KB%kb%byte
echo 已用空间 %kg%.%kgm1%%kgm2% GB
pause
exit
:zzz
set /a n+=%1
goto :eof