linux脚本乘法运算符 使用shell脚本实现加法乘法运算

编写一个shell脚本，实现加法和乘法运算。

#!/bin/bash#Function:num1+num2 num3*num4sum(){read -p "please key in first number:" num1read -p "please key in second number:" num2let num3=${num1}+${num2}echo -e "\033[32m $num1 + $num2 = $num3 \033[0m"}#############cf(){read -p "please key in first number:" num3 read -p "please key in second number:" num4 let num3=${num3}*${num4} echo -e "\033[32m $num3 * $num4 = $num3 \033[0m"}menu(){echo "###############calculate#################"echo -e "1\tsum"echo -e "2\tcf"echo -e "3\texit"read -p "please key in your choose option:" option}################main(){while [ 1 ]doclearmenucase $option in 1)sumecho "Enter any key continue"read -n 1clear;;2)cfecho "Enter any key continue"read -n 1clear;;3)exit;;*)echo "输入错误，请重新输入！"clearmenu;;esacdone}main;