Why so complicated? ;) 

my $count=0;
$count += substr($dna, $_, 1) =~ /[CG]/ for map 3 * $_, 1 .. length($d
+na)/3;
print $count;

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Examine what is said, not who speaks.

In reply to Re: Re^2: for loops by BrowserUk
in thread Count every 3rd base occurence by Anonymous Monk

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