use strict;
use warnings;

my (@s,@m);
$s[0] = "123456789";
$s[1] = "987654321";
$s[2] = "123456789";
$s[3] = "987654321";
$s[4] = "123456789";
$s[5] = "987654321";
$s[6] = "123456789";
$s[7] = "987654321";
$s[8] = "123456789";

push @{$m[$_]}, split //,$s[$_] for(0..$#s); # make the matrix

my(@f1,@f2,@f3);
@f1 = ($m[0],$m[1],$m[2]); # divide
@f2 = ($m[3],$m[4],$m[5]); # into groups
@f3 = ($m[6],$m[7],$m[8]); # to print
format =
+-----------------------+
| @ @ @ | @ @ @ | @ @ @ |~~
@{shift @f1}
|-------+-------+-------|
| @ @ @ | @ @ @ | @ @ @ |~~
@{shift @f2}
|-------+-------+-------|
| @ @ @ | @ @ @ | @ @ @ |~~
@{shift @f3}
+-----------------------+
.
write;