Change 
my $r = join',','a'..'z';

[download]
to 
my $r = 'A,T,G,C';

[download]
in BrowserUK's example and it will solve your problem.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

My blog: Imperial Deltronics

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