Firstly I'd avoid using $a and $b (in case they interfere with sort functions you may write later). Next, it is probably best to first write what you mean and then decide whether it needs factorising into a grep. But we can't know that without knowing what your pairwise structure looks like.

One world, one people

In reply to Re: Hash Lookup by anonymized user 468275
in thread Hash Lookup by eagle504

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