for /f "skip=1 tokens=1* delims=:" %%x in ('findstr /r /n "^" "FILENAME.TXT"') do echo.%%y >"FILENAME.TXT"
空
for /f "skip=1 tokens=1* delims=:" %%x in ('findstr /r /n "^" "FILENAME.TXT"') do echo.%%y >>"FILENAME.TXT"
倍