in reply to Generate all unique combinations of 1 and 0 using specified length of "0"-string and count of 1's
For computational efficiency, you'll want to use an "iterator" pattern. Search here, there are quite a few interesting posts about this. You can also read about them in section 4.3.1 of Dominus' Higher Order Perl. There are also quite a few CPAN modules that might help.
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