1 #!/usr/bin/perl
 2 use strict;
 3 use Getopt::Long;
 4 my ($matrix,$num,$flag);
 5 my $maxnum=9;  
 6 GetOptions("n:i"=>\$num,
 7         "h"=>\$flag,);
 8 die "num is not valid" if (!defined $num)||$num>$maxnum||$num<0;
 9 for(my $i=0;$i<=$num;$i++){
10     for(my $j=0;$j<=$num;$j++){
11         $matrix->[$i][$j]=$i*$j;
12     }
13 }
14 my $format='%2d ' x (@{$matrix});
15 printf "i*j $format\n",0 .. $num;
16 foreach (0 .. $num){
17     printf "%2d $format\n",$_,@{$matrix->[$_]};
18 }