DOS删除某目录中几天前的文件

@echo off&setlocal enabledelayedexpansion
set ds=7
set di=d:\Soft\logs
set "dy=%date:~,4%"
set "dm=%date:~5,2%"
set "dd=%date:~8,2%"
echo 当前日期为：%dy%年%dm%月%dd%日
echo.
if %dm:~,1%==0 set "dm=%dm:~1%"
if %dd:~,1%==0 set "dd=%dd:~1%"
set/a "dd-=ds"
if !dd! gtr 0 goto ok
echo 正在计算%ds%天前的日期...
:ry
set /a "feb=^!(!dy!&3)+28"
if "%dy:~2,2%" equ "00" set/a "feb=feb-1+^!(dy:~,2&3)"
if %feb%==29 echo %dy%年是闰年
echo.
:tyt
set n=0
set/a "dm-=1"
if %dm% equ 0 (
set/a "dy-=1,dm=12,dd+=31"
if %dd% gtr 0 (goto ok )else goto ry )
for %%a in (31 %feb% 31 30 31 30 31 31 30 31 30 31) do (
    set/a n+=1
    if !n! equ %dm% set/a "dd+=%%a")
if %dd% leq 0 goto tyt
:ok
set/a "ymd=dy*10000+dm*100+dd"
echo.
echo 前%ds%天的日期是%ymd:~,4%年%ymd:~4,2%月%ymd:~6,2%日
echo 正在获取文件日期再进行比较
echo 并删除%ds%天前创建并且%ds%天内未修改过的文件...
cd/d "%di%"
for /f "delims=" %%i in (‘dir/a/a-d/b‘)do (

Set "strymdx=%%~ti%"
Set "xdy=!strymdx:~,4!"
Set "xdm=!strymdx:~5,2!"
Set "xdd=!strymdx:~8,2!"
Set "ymdx=!xdy!!xdm!!xdd!"

Rem set ymdx=!ymdx~,4!!ymdx~5,2!!ymdx~8,2!
echo %%i,ymd=%ymd%,ymdx=!ymdx!,ti=%%~ti
if !ymdx! lss %ymd% (
    if "%%i" neq "%~nx0" del/f "%%i"))
echo.
echo 处理完毕！即将退出...
@pause