please someone that help me whith this problem http://www.spoj.com/problems/POWERUP/ i'm using the fermat little theorem a^p-1=a (mod p). Grace in advance
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please someone that help me whith this problem http://www.spoj.com/problems/POWERUP/ i'm using the fermat little theorem a^p-1=a (mod p). Grace in advance
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By Fermat theorem a^phi(m) == a (mod m) => a^(phi(m) — 1) == 1 (mod m). In this problem m == 10^9 + 7 is prime, so phi(m) == m — 1.
So A^(B^C) (mod m) == A^(B^C mod (phi(m) — 1)) (mod m) == A^(B^C mod (m — 2)) (mod m).
Yes, I'm applying that theory,but the judge sentence is wrong answer. I would appreciate if you provide me extreme cases in which my code it can fail
You are wrong, aφ(m) = 1.
Savinov thanks, it really aφ (m) = 1.
It's Euler theorem, not Fermat's theorem...
There are some tricky cases when a mod p == 0
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