2 nested loops is bad, much less 4. I assure you that rethinking the problem with the proper data structure will make the iterative complexity much less. Since it looks like you are doing something with permuations, check out How do I permute N elements of a list?

Provide a description of your problem, and like the monks above said, we may be able to help a bit more...

In reply to Re: nested combinations: algorithm advice? by perlfan
in thread nested combinations: algorithm advice? by revdiablo

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