shell编程之循环结构——猜数程序

#!/bin/bash
##filename:guest_number.sh
#对被猜中的树num进行赋值
#$RANDOM是一个系统随机数的环境变量，模100运算用于生成1~100的随机整数
num=$((RANDOM%100))
#使用永真循环，条件退出的方式接收用户猜测并进行判断
while [ 1 ];do
read -p "Please input a number:" user_num
if [ $user_num -lt $num ]; then
echo "The number you inputed is less then my NUMBER."
elif [ $user_num -gt $num ]; then
echo "The number you inputed is greater then my NUMBER."
elif [ $user_num -eq $num ]; then 
echo "Congratulate:my NUMBER is $num."
break
fi

done

break提供了以下两种循环控制语句

1).break：用来跳出循环

2).continue:只会跳过本次循环，忽略本次循环剩余的代码，进入循环的下一次迭代