Congruence
If the integer a and the integer b is divided by a positive integer equal to the number m of the remainder, called a, b congruent modulo m, referred to as a≡b (mod m).
Fermat's Little Theorem
If p is a prime number, then for any integer a, there are A p ≡a (MOD p)
For not a multiple of p, a p. 1- ≡1 (MOD p).
Euler's theorem
If positive integers a, n prime, then A φ (n) ≡1 (n-MOD), where φ (n) is the Euler function.
The algorithm better understand some of the competition guidelines.
Simplified multiplication remainder based on the closed mold m.
Extended Euclid
For any integer a, b, there is a pair of integers x, y, satisfying ax + by = gcd (a, b).
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