use strict;
use warnings;
use Data::Dumper;

my @aoa1;
my @aoa2;

my $row=0;
while (<DATA>){
    chomp;
    push @{$aoa1[$row]}, split /\s+/;
    $row++;
    push @aoa2,        [ split /\s+/ ];
}

print Dumper \@aoa1;
print Dumper \@aoa2;

__DATA__
A1 A2 A3
B1 B2 B3
C1 C2 C3