Further to Khen1950fx's reply: Dominus's excellent Higher-Order Perl (freely downloadable here) discusses general iterative approaches to solving combination/permutation problems, with a bio-application example in section 4.3.2 "Genomic Sequence Generator".

In reply to Re: Is it possible to generate all possible combinations of 2-letter and 3-letter words in perl? by AnomalousMonk
in thread Is it possible to generate all possible combinations of 2-letter and 3-letter words in perl? by supriyoch_2008

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