Modular inverse modulo prime
Given an integer a and a prime p with a not divisible by p, return the modular multiplicative inverse of a modulo p (the unique value x in [0, p) with a*x = 1 mod p). Constraints: 1 <= a < 1e18, 2 <= p <= 1e9+7 and p is prime, gcd(a, p) = 1.
Implement
mod_inverse(a: int, p: int) → intExamples
in
[3,7]out5What a strong answer looks like
State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.
0:00 of about 20 min
solution.py
InputExpectedGot
[3,7]5not run yetsample