I prefer an easier to understand approach than diotalevi's - if your string is not too big, you can split it into an array where each element of the array is one character of the string, and then search through the array, something like this: 
   my $mystring = "AABAABBBB";
   my @myarray = split //, $mystring;
   my $ct = 0;
   foreach my $element (@myarray) {
      if ($element eq "B") {
         push(@myoccurrences, $ct);
      }
      $ct++;
   }

[download]
NOTE that I'm sure that diotalevi's solution is much more efficient than mine. But this one I can understand simply, and that one I have to sit and think about ;-)

HTH.

In reply to Re: Pattern match location finding by hmerrill
in thread Pattern match location finding by feloniousMonk

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