Anonymous Monk,
You can check out the pack/unpack tutorial for more information, but here was my logic. 
my $pairs = "a2" x ((length $dna)/2);
#  The x operator (perldoc perlop) repeats LHS string times the RHS


$seq{$_}++ for unpack $pairs, $dna;
#  Break string up into a list of 2 char strings
#  Increment the corresponding hash value by 1

[download]
Cheers - L~R

In reply to Re: Re: Re: Re: Re: input record separator help by Limbic~Region
in thread input record separator help by Anonymous Monk

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