LinuxShell脚本编程基础5--数值,字符串,文件状态测试，((..))和[[..]]的使用

! /bin/bash
echo "enter a score:"
read num1
if [ $num1 -ge 80 ]
then
 echo "Very Good"
elif [ $num1 -lt 80 -a $num1 -ge 60 ]
then
 echo "Good"
else
 echo "Low"
fi

echo "enter a score:"
read num2
if (($num2 >= 80))
then
        echo "Very Good"
elif [[ $num2 -lt 80 && $num2 -ge 60 ]]
then
        echo "Good"
else
        echo "Low"
fi

#! /bin/bash
echo "enter filename or workname:"
read name1
if [ -z $name1 ]
then
        echo "your enter is null"
        exit
else
        if [ -f $name1 ]
        then
                echo "this is a file"
        elif [ -d $name1 ]
        then
                echo "this is a workspace"
        else
                echo "not found file or workspace"
        fi
fi