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LovesProgramming's blog

Help with modulo function needed .
By LovesProgramming, history, 5 years ago, In English

I want to calculate ((a/b)^n)%e.

I know, how to calculate (a/b)%e; the formula is: (a%e * (b^-1%e))%e.

So, the answer to the above question should be,

(a^n%e * ((b^n)^-1)%e)%e

Am I right ?

Plus, I know how to calculate b^-1 , but I want to know, how to calculate (b^n)^-1

Thanks .

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5 years ago, # |
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Is e a prime number? Let x = (a/b)%e then ((a/b)^n)%e = (x^n)%e.

UPD: ((b^n)^-1)%e = ((b^-1)^n)%e

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    5 years ago, # ^ |
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    I've found a nice way :-) Thanks, anyways!!

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      5 years ago, # ^ |
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      (b^n)^-1 you can do fast exponentiation with modulo then invert it as it is written.

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