[Iska]

Код:

@echo off
setlocal enableextensions enabledelayedexpansion

set /p sIP=Enter IP: 
set /p sLastPartIP=Enter last part of IP: 

for /f "tokens=1-3 delims=." %%i in ("%sIP%") do set sNewIP=%%i.%%j.%%k.%sLastPartIP%

echo [%sNewIP%]

endlocal
exit /b 0