唯尘

@echo off
setlocal enabledelayedexpansion
set /a a=%random%%%5*9
echo a=%a%
set /a b=(%random%%%3+1)*3
echo b=%b%
set "fuhao=+-*/"
set /a n=0

:calc
if "!fuhao:~%n%,1!"=="" echo 循环完毕 & pause>NUl & goto :eof
set /a rs=%a%!fuhao:~%n%,1!%b%
echo a !fuhao:~%n%,1! b = !rs!
set /a n+=1
goto :calc
看完大佬的代码自己默写了一遍