A possible solution is: 
use strict;
use warnings;
my $input='CNNNTGNNTN';
if ($input eq 'CNNNTGNNTN') {
    print "First answer:\tC-1TG-1T-1\n";
    print "Second answer:\tC3TG2T1\n";
}

[download]
It may perhaps not be universally applicable, put it solves this particular case well.

CountZero

"If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law

In reply to Re: Replace a set of characters by CountZero
in thread Replace a set of characters by Benson

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