shell 99乘法口诀表

需求：使用shell脚本实现99乘法口诀表

shell脚本：

[root@localhost opt]# vim 99.sh 
#!/bin/bash
for ((i=1;i<=9;i++));do
   for ((j=1;j<=i;j++));do
     echo -n "$i x $j = $(expr $i \* $j) "
    if [ $j -eq $i ];then
    echo -e "\n"
    fi
 done
done

给与权限，执行脚本：

[root@localhost opt]# chmod +x 99.sh 
[root@localhost opt]# ./99.sh 
1 x 1 = 1 

2 x 1 = 2 2 x 2 = 4 

3 x 1 = 3 3 x 2 = 6 3 x 3 = 9 

4 x 1 = 4 4 x 2 = 8 4 x 3 = 12 4 x 4 = 16 

5 x 1 = 5 5 x 2 = 10 5 x 3 = 15 5 x 4 = 20 5 x 5 = 25 

6 x 1 = 6 6 x 2 = 12 6 x 3 = 18 6 x 4 = 24 6 x 5 = 30 6 x 6 = 36 

7 x 1 = 7 7 x 2 = 14 7 x 3 = 21 7 x 4 = 28 7 x 5 = 35 7 x 6 = 42 7 x 7 = 49 

8 x 1 = 8 8 x 2 = 16 8 x 3 = 24 8 x 4 = 32 8 x 5 = 40 8 x 6 = 48 8 x 7 = 56 8 x 8 = 64 

9 x 1 = 9 9 x 2 = 18 9 x 3 = 27 9 x 4 = 36 9 x 5 = 45 9 x 6 = 54 9 x 7 = 63 9 x 8 = 72 9 x 9 = 81