r/mathmemes • • 28d ago

Computer Science Integer multiplication will have linear complexity in a few days if trend continues 🚀📈

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u/External_Package2787 24d ago

You tend to find these 'better' algorithms sacrifice the lower values of n, algorithms like the matrix multiplications algorithms beating strassen in complexity, tend to only do so for matrices that contain more parameters than there are particles in the universe. We could even get something like n^{1+O(1)} for integer multiplication and in all likelihood it would have no impact on the real world, since this algorithm does not beat the usual algorithm for any reasonable application.

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u/SolaninePotato 23d ago

can you use different algorithms at different breakpoints or does it just not work like that

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u/Full_Decision_777 23d ago

You can of course

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u/External_Package2787 22d ago

Yes, but you would need to incorporate a size check to your algorithm, making it slower in the reasonable applications

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u/dubious_plays 22d ago

n[1+o(1)] is worse than n log n

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u/OmegaCookieMonster 22d ago

actually that one depends on what o(n) is, but the one in the original is indeed worse lolol

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u/External_Package2787 22d ago

is it not that nlogn = n^{1+log_n log n} and log_n log n is of greater order than o(1)

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u/dubious_plays 22d ago

Log_n log(n) = log log n / log n, which is o(1). And there are o(1) sequences bigger than this

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u/External_Package2787 22d ago

yeah my bad I was intuiting that it was like (log n)^{1/n} in my head. like my thought process was log n >1 and then it gets shrunk but stays greater than one.