中国DOS联盟

@echo off
set P=2
set "r=d:\指定目录"
for /f "tokens=1-3 delims=-:/ " %%a in ("%date%") do set Y=%%a&set M=%%b&set D=%%c
if %M:~0,1%==0 set M=%M:~1%
if %D:~0,1%==0 set D=%D:~1%
set/a D-=P
if %D% leq 0 call:D %D%
set M=0%M%&set D=0%D%
setlocal enabledelayedexpansion
for /f "tokens=1,3*" %%a in ('dir /a-d/s/tc "%r%"') do (
        setlocal enabledelayedexpansion
        set a=%%a&set c=%%c
        if not "!a!"=="!a:-=!" if "!a!" lss "%Y%-%M:~-2%-%D:~-2%" del /a/f "!c!"
        Endlocal
)
exit
:D
set/a M-=1,Y-=!M,M+=!M*12,"C=!(M-4)|!(M-6)|!(M-9)|!(M-11)","D+=!(M-2)*(28+(!(Y%%4)&!!(Y%%100))|!(Y%%400))+C*30+(!!(M-2)&!C)*31"
if %D% leq 0 goto:D