use strict;
use warnings;

use Data::Dumper;

open my $inFH, q{<}, \ <<__EOD__ or die $!;
1111111
2222222
3333333
__EOD__

my @AoA;
my $x = 0;

while ( <$inFH> )
{
    chomp;
    $AoA[ $x ++ ] = [ undef, split m{} ];
}

close $inFH or die $!;

print Data::Dumper->Dumpxs( [ \ @AoA ], [ qw{ *AoA } ] );

##</code><code>##

@AoA = (
         [
           undef,
           '1',
           '1',
           '1',
           '1',
           '1',
           '1',
           '1'
         ],
         [
           undef,
           '2',
           '2',
           '2',
           '2',
           '2',
           '2',
           '2'
         ],
         [
           undef,
           '3',
           '3',
           '3',
           '3',
           '3',
           '3',
           '3'
         ]
       );

##</code><code>##

use strict;
use warnings;

use Data::Dumper;

open my $inFH, q{<}, \ <<__EOD__ or die $!;
1111111
2222222
3333333
__EOD__

my @AoA;

while ( <$inFH> )
{
    chomp;
    push @AoA, [ undef, split m{} ];
}

close $inFH or die $!;

print Data::Dumper->Dumpxs( [ \ @AoA ], [ qw{ *AoA } ] );