C高级第三天作业

 #!/bin/bash
 for i in {1..9}
 do
     for ((j=1 ;j<=i;j++))
     do
         echo -n -e "$i*$j=$((i*j))\t"
     done
     echo -e "\n"
 done                                    
 i=1
 

while((i<=9))
 do
     j=1
     while((j<=i))
     do
         echo -n -e "$i*$j=$((i*j))\t"
         ((j++))
     done
     echo -e "\n"
     ((i++))
 done

 九九乘法表

#!/bin/bash
read -p "输入>>>>>" arr
for ((i=0;i<=arr;i++))
do
    for((j=1;j<=arr-i;j++))
    do
        echo -n " "
    done
    for((j=1;j<=2*i-1;j++))
    do
        echo -n "*"
    done
    echo -e "\n"
done

i=0
j=1
while ((i0))
    do              
        echo -n " "
        ((a-=1))
    done
    b=$((2*i+1))
    while ((b>0))
    do
        echo -n "*"
        ((b-=1))
    done
    echo -e "\n"
    ((i+=1))
done

金字塔

#!/bin/bash
read -p "输入>>>>>>" a b c
case $b in
    +)
        echo $a+$c=$((a+c))
        ;;
    -)
        echo $a-$c=$((a-c))
        ;;
    *)
        echo $a*$c=$((a*c))
        ;;
    /)
        echo $a/$c=$((a/c))
esac                          

四则运算

#!/bin/bash
read -p "输入>>>>>" app
read -p "输入>>>>>" rdd
if [ $rdd == yes -a $rdd == y -a $rdd == Yes ]
then
    sudo apt-get install "$app"                  
fi

下载软件

#!/bin/bash
read -p "输入>>>>>>" add
j=${#add}
for((i=j-1;i>=0;i--))      
do
    str=${add:i}
    add=${add:0:i}
    str1=$str1$str
done
echo $str1

i=$((j-1))
while ((i>=0))
do
    str=${add:i}
    add=${add:0:i}
    str1=$str1$str
    ((i--))
done
echo $str1

倒转字符