COCI 08 - Periodni
Author: Benjamin Qi
/*** Description: modular arithmetic operations* Source:* KACTL* https://codeforces.com/blog/entry/63903* https://codeforces.com/contest/1261/submission/65632855 (tourist)* https://codeforces.com/contest/1264/submission/66344993 (ksun)* also see https://github.com/ecnerwala/cp-book/blob/master/src/modnum.hpp (ecnerwal)* Verification:* https://open.kattis.com/problems/modulararithmetic