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Imagine you have an algorithm that fills in random squares on a grid (like pic related) with black based on a seed.
Is it possible to, given a grid that a user has filled some squares in, reliably find a seed that will give the same output using the algorithm described above?
Is it possible to do this with at worst O(n) complexity?
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not if it is truly random.
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>>56499000
obviously it's not. i said based on a seed.
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>>56498981
>that fills in random squares on a grid (like pic related) with black based on a Seed.
No, as long as you have a randomness factor you cannot magically recover the Seed value from your result with O(n) complexity
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Are you asking to do this in practice, or just for the theory?
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>>56499136
Just asking for theory, but it would be very useful in practice if it's possible.
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>>56499197
Why would it be 25! And not 2^25?
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>>56499197
yes that's why i said O(n)
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>>56499210
Because when one is on it's taken out of the possible spaces left that can be on. 25^25 would be the ways to arrange 25 5x5 boards with 1 square each.
Or something like that. Don't quote me.
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>>56499189
Okay, well just to be clear, all you're actually asking is to generate a 25-bit number.
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