Linux之簡單的shell編程

分享幾個shell程序，便於linux期末復習

 

 

 

1.判斷用戶輸入的數是否為回文數

 1 #!/bin/bash
 2 read in
 3 res=`echo $in|rev` 4 if [ $res -eq $in ] 5 then 6 echo "$in is a huiwenshu!" 7 elif [ $res -ne $in ] 8 then 9 echo "$in not is a huiwenshu" 10 fi

 2.計算用戶輸入的一個數的階乘

#!/bin/bash
sum=1
i=1
read n
while [ $i -le $n ]
do
sum=$[$sum*$i]
i=$[$i+1]
done
echo "sum=$sum"

3.判斷用戶輸入的數是否為素數

#!/bin/bash
read num
declare -i count=0
for n in `seq 1 $num`
do
        if [ $((num%n)) -eq 0 ]
        then
        count=$[$count+1]
        fi
done
if [ $count -eq 2 ]
then
        echo "$num is a prime num"
else echo "$num not is a prime num"
fi

4.計算斐不那楔數列的的前n項和

#!/bin/bash
read num
a=1           
b=1
c=0 
sum=0
for((i=0;i<num;i++))
do
        echo "$a"
        let sum+=a
        let c=a+b 
        let a=b 
        let b=c 
done
echo "sum=$sum"