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纯P 环境 WIN7

@echo off&setlocal enabledelayedexpansion
(for /f "delims=" %%i in (1.txt) do set /an+=1&if !n! leq 48 echo %%i)>$
clip<$
>$ more +48 1.txt
move $ 1.txt
pause
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@echo off&setlocal enabledelayedexpansion
del $* 2>nul
for /f "delims=" %%i in (1.txt) do set /an+=1&if !n! gtr 48 (>>$$ echo %%i)else >>$ echo %%i
clip<$&move $$ 1.txt >nul&del $*
pause
复制代码