shell编程，读取一个数，判断这个数是奇数还是偶数？

#!/bin/bash

echo “please input a number:”

read line

if ;then

echo oushu

else

echo jishu

fi

sh-3.2# sh 1

please input a number:

4

oushu

sh-3.2# sh 1

please input a number:

5

jishu