@echo off &setlocal enabledelayedexpansion
mode con cols=100 lines=25
set a=0
for /f "delims=" %%a in ('dir *.txt /s /b') do (
  set /a for+=1
  set file_!for!=%%~snxa
  echo,!for!	%%~nxa
)
:input
 set /p input="choose the code: "
if not defined file_%input% (cls &goto :input)
for /f "delims=" %%a in (!file_%input%!) do (
  set now=%%a
  call :read -!now!
  echo,
)
pause
exit
:read
 set now=%*
 :r-1
 set now=%now:~1%
 if "%now%"=="" goto :eof
 set /p=%now:~0,1%<nul&for /l %%a in (1,1,6) do ping -n 1 127.1>nul
 goto :r-1