Isn't the $seen{ $rawData } = 1; line only needed if it's necessary to check for duplicates within each individual array, as opposed to only checking for duplicates between the two arrays? If checking for such duplicates within each array isn't necessary then I think that could be a small efficiency gain too because the lookup hash wouldn't keep growing as the loop iterated.

I love it when things get difficult; after all, difficult pays the mortgage. - Dr. Keith Whites
I hate it when things get difficult, so I'll just sell my house and rent cheap instead. - perldigious

In reply to Re^2: Fastest way to merge (and de-dup) two large arrays? by perldigious
in thread Fastest way to merge (and de-dup) two large arrays? by technojosh

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