Print Reverse nxn multiplication table

I. Experimental requirements:

• Given any one of the characters N (n>0), then print the reverse multiplication table of the NXN.

two. Problem solving :

#/!bin/bash
#

#define Function
Nxn_fun () {

Local i=$1 #定义一个局部变量i控制外层循环
While [$i-ge 1];d o
Local j= $i #定义一个局部变量j控制内层循环
While [$j-ge 1];d o
ECHO-E-N "$i * $j =$[i*j]\t"
Let j--
Done
echo #换行
Let i--
Done
}

#main
Flag=$ (echo "$" | sed ' s/[0-9]//g ' | wc-c) #判断脚本参数是整型还是字符

if [! $#-eq 1];then #判断脚本参数个数
echo ">_<| | | It's awkward ~!!! usage:$ (basename) num. "
Exit 5
elif [! $Flag-eq 1];then #Flag值不等于1则给定的脚本参数为字符型

echo ">_<| | | It's awkward ~!!! usage:$ (basename) num. " #表情符号还是挺不错的

Exit 5

Fi

Nxn_fun $
[$?-eq 0]&&echo "Print $1*$1 multiplication table complete (^_^) hehe" | | echo "Function execution error, please check ... (B_d) Wearing a pair of glasses " #函数执行成功则打印乘法表

Three. Experimental results:

Four. Experimental thinking?

1. How can I tell if the parameters given by the script are characters or integers, there is no other way?

2. The outer while loop parameters can be directly to $, how to change, can't why?

Five. The comforting code snippet is:

Flag=$ (echo "$" | sed ' s/[0-9]//g ' | wc-c)

Print Reverse nxn multiplication table