echo off
setlocal enabledelayedexpansion
mode con cols=50 lines=20
set liejia=ok
set p= 
set hangjia=ok&set hangjian=
cls
for /l %%a in (1 1 800) do (
if defined hangjia (
for /l %%i in (1 1 !hang!) do (echo.)
if defined liejia (set p= !p!) else (set p=!p:~1!)
set /a hang=hang+1
if !hang! EQU 20 (set hangjia=&set hangjian=ok&set /a hanga=19)
if not "!p:~47,1!"=="" set liejia=
if "!p!"=="" (set liejia=ok&set p= )
)
if defined hangjian (
for /l %%i in (1 1 !hanga!) do (echo.)
set /a hanga=hanga-1
if defined liejia (set p= !p!) else (set p=!p:~1!)
if !hanga! EQU -1 (set hangjia=ok&set hangjian=&set /a hang=1)
if not "!p:~47,1!"=="" set liejia=
if "!p!"=="" (set liejia=ok&set p= )
)
set /p=!p!●<nul
for /l %%n in (1 1 200) do ver>nul
cls
)