What's the right approach of solving this Hackerearth Problem?
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What's the right approach of solving this Hackerearth Problem?
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There's an editorial to this problem. If you're still confused after reading it, check Trick #4 here and modification of Sieve of Eratosthenes here.
Can you please Elaborate the 4 trick?
AN % MOD = AN % phi(MOD) % MOD
This is a natural outcome of Euler's Theorem. If you multiply a number phi(MOD) times modulo MOD you get 1. Suppose N/phi(MOD) = t.
So A^N % MOD can be written as ((A^phi(MOD))^t)%MOD * (A^(N%phi(MOD)))%MOD. Since the first term is 1 by Euler's Theorem you are left with (A^(N%phi(/MOD)))%MOD.
Pardon my illiteracy with respect to LATEX.