Re:Anime fans stumbled upon a mathematical proof
by dumbfounder on Thursday March 06, 2025 @09:28PM
(#43286964)
Think about this. You need to calculate the number of permutation for 4 digit codes. Then you need to arrange them in every order possible to brute force. So that’s 4!!. That’s a lot: roughly 620000000000000000000000 combos.
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Re:Anime fans stumbled upon a mathematical proof
by somenameforme on Thursday March 06, 2025 @10:24PM
(#43287160)
If you're not making some joke that I'm missing it's just 10^4 = 10000, which is a just a fancier way of saying 0000-9999.
Re:Anime fans stumbled upon a mathematical proof
by fc417fc802 on Friday March 07, 2025 @02:36AM
(#43287982)
10^4 permutations. Which you then permute again except the second time you're overlapping them to search for the shortest possible sequence.
Re:Anime fans stumbled upon a mathematical proof
by genewitch on Thursday March 06, 2025 @10:09PM
(#43287114)
Or it's 10000?
Re:Anime fans stumbled upon a mathematical proof
by SamBam on Friday March 07, 2025 @01:36PM
(#43292849)
That's the number of possible codes. Not the number of possible ways you could arrange all 10000 codes to see which ordering contains the most shortcuts.
Re:Anime fans stumbled upon a mathematical proof
by genewitch on Friday March 07, 2025 @05:24PM
(#43295473)
i have a python script running through that right now to find "the shortest" and it's been burning a single core for at least 6 hours. So it looks like you are right and i am wrong ;-)
i assume my pc on a single core can do ~1billion permutations per second, this will take 19,647 millennia. AFK.
what do you think the chances are, if i let this run, that it would find a shorter solution than 625 keypresses? the naive De Bruijn algorithm popped that out in like 2 seconds.