shell脚本：猜数字游戏

[root@yonglinux ~]# cat guess.sh
#!/bin/bash
#guess number game;
n=$[$RANDOM%100]
while :
do
read -p "please input a number: " n1
n2=`echo $n1 | sed 's/[0-9]//g'`
if [ ! -z $n2 ]
then
echo "your number is not a number."
continue
fi
if [ $n1 == $n ]
then
echo "you are all right."
break
elif [ $n1 -gt $n ]
then
echo "bigger."
continue
else
echo "smaller."
continue
fi
done

[root@yonglinux ~]# sh guess.sh
please input a number: 56
bigger.
please input a number: 33
bigger.
please input a number: 15
bigger.
please input a number: 7
smaller.
please input a number: 10
bigger.
please input a number: 8
smaller.
please input a number: 9
you are all right.