实现代码1
@echooff&setlocalenabledelayedexpansion
for/f"delims="%%ain('dir/b*.txt')do(
set/an+=1
ifnotexist"!n!.txt"(ren"%%a""!n!.txt")elsecall:loop"%%a"
)
pause&exit
:loop
set/an+=1
ifexist"!n!.txt"gotoloop
ren"%~1""!n!.txt"
goto:eof