Sans any context whatsoever, solving the immediate problem of reading and slicing up the file data seemed most helpful.

With the small amount of additional context you have added a fuller implementation would be:

use warnings;
use strict;

my @lines;

while (<DATA>) {
    chomp;
    push @lines, [unpack ("(a2)*", $_)];
}

__DATA__
0912203749
0725284648
0608294149
0622424347
1219303436
1729313449
1015162331
[download]

which pushes arrays of numbers into an array of lines creating a two dimensional array that you can use in subsequent processing:

for my $column (0 .. 4) {
    my @byColumn = map {$_->[$column]} @lines;
    print "@byColumn\n";
}
[download]

prints:

09 07 06 06 12 17 10
12 25 08 22 19 29 15
20 28 29 42 30 31 16
37 46 41 43 34 34 23
49 48 49 47 36 49 31
[download]