#cryptoctf2021 #!/usr/bin/env python3 from Crypto.Util.number import * from gmpy2 import gcd from random import randint import sys import hashlib from flag import flag def lcm(a, b): return (a * b) // gcd(a,b) def gen_params(nbit): p, q = [getPrime(nbit) for _ in range(2)] n, f, g = p * q, lcm(p-1, …