modular exponentiation?

[ijabbott]

(06-24-2018 09:08 PM)Valentin Albillo Wrote:  3) Actually, I've been sometimes in charge of selecting programmers to hire and if I were to pose this same question to the people applying for the job and some of them would produce code which computed the integer powers N^N by performing N multiplications in a loop, both their code and their application would've been thrown to the garbage bin at once, for being so utterly inefficient.

I'd choose people who are resourceful, even if they don't know every algorithm off by heart. I've been programming professionally for 34 years and never had any reason to use modular exponentiation, let alone implement it efficiently. (If I specialized in cryptography, it would be a different matter!). I only really discovered the fast binary algorithm for modular exponentiation through solving challenges on HackerRank, since I figured there probably had to be a faster than O(n) algorithm so I went looking on Wikipedia to find it.