#!/usr/bin/perl
use strict;
use warnings;

my $inputseq = "AATGGTTTCTCCCATCTCTCCATCGGCATAAAAATACAGAATGATCTAA";


my $regex = '\w+(ATG\w*T(AG|AA|GA))\w+';

find_coding($inputseq);

sub find_coding {
        my ( $seq ) = @_;
        while ( $seq =~ /($regex)/g ) {
                my $match = $1;
                my $sequence = find_coding($match);
                my $allmatch = find_coding($sequence);
                print "Coding region: $allmatch", "\n";
        }
}