数的比较输出
实例1
#!/bin/bash
Num1=100
Num2=200
if [ $Num1 -gt $Num2 ] ;
then
echo "num1>num2"
else
echo "num2>num1"
fi
if [ $Num1 -eq $Num2 ];
then
echo "num1=num2"
else
echo "num1!=num2"
fi
实例2
#!/bin/bash
read -p "请输入a的值:" a
if [ "$a" -gt 3 ]
then
echo "a大于3"
elif [ "$a" -eq 3 ]
then
echo "a等于3"
elif [ "$a" -lt 3 ]
then
echo "a小于3"
else
echo "没有这个值"
fi
成绩的if判断
#!/bin/bash
read -p "Please input you score: " a
if [ "$a" -lt 60 ]
then
echo "You didn'it pass the exam."
elif [ "$a" -ge 60 ] && [ "$a" -lt 90 ]
then
# elif相对if，再做一次判断
echo "Good!You passed the exam."
else
echo "Very good!Your score is very high."
fi
变量运算
a=1
b=2
sum=$(($a+$b))
echo "$a+$b=$sum"
用户交互DIY
read -p "请输入X的值:" x
read -p "请输入Y的值:" y
sum=$(($x+$y))
echo "X和Y的和为：$sum"
