[05:32][nick:~/dev/perl_dev/test/monks]$ cat 1133944.pl
#!/usr/bin/env perl     
use strict;
use warnings;
    
print " Enter dimension : ";
my $n = <STDIN>;



my $k=1;
my @matrix;

for(my $i = 0; $i < $n; $i++) { 
  for(my $j = 0; $j < $n; $j++) {
    $matrix[$i][$j]= $k++; 
  }
}

print " the matrix : \n\n";

for(my $i = 0; $i < $n; $i++) { 
  for(my $j = 0; $j < $n; $j++) {
    print "$matrix[$i][$j]  ";
  }
  print "\n";
}


##</code><code>##

[05:31][nick:~/dev/perl_dev/test/monks]$ perl 1133944.pl
 Enter dimension : 3.14159
 the matrix : 

1  2  3  4  
5  6  7  8  
9  10  11  12  
13  14  15  16  

##</code><code>##

[05:32][nick:~/dev/perl_dev/test/monks]$ cat 1133944-2.pl
#!/usr/bin/env perl
use strict;
use warnings;

print " Enter dimension : ";
my $n = <STDIN>;

$n--;

my $k = 1;
my @matrix;

for my $i (0..$n) {
  for my $j (0..$n) {
    $matrix[$i][$j]= $k++;
  }
}

print " the matrix : \n\n";

for my $i (0..$n) {
  for my $j (0..$n) {
    print "$matrix[$i][$j]  ";
  }
  print "\n";
}

##</code><code>##

[05:33][nick:~/dev/perl_dev/test/monks]$ perl 1133944-2.pl
 Enter dimension : 3.14159
 the matrix : 

1  2  3  
4  5  6  
7  8  9