#!/usr/bin/perl

# http://perlmonks.org/?node_id=1201579

use strict;
use warnings;

my $haystack = 'AGCTTCTTGCTTCTTGC';
my $needle = 'GCTTCTTGC';
my @positions;

push @positions, $-[0] + 1 while $haystack =~ /(?=$needle)/g;

print "@positions\n";
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