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

my(@codons)= qw(ATG GTG);
my $dna = "AAAATGGGGTAAGTGAACGGGTAA";

my $splitter= join('|', @codons);

my @sequences= split /($splitter)/,$dna;
shift @sequences;

my $codon= 1;
foreach (@sequences) {
	if ($codon) {
		print $_,"-";
	}
	else {
		print $_,"\n"
	}
	$codon= not $codon;
}

##</code><code>##

ATG-GGGTAA
GTG-AACGGGTAA