#pbctf_2021 #rbtree #!/usr/bin/env python3 from Crypto.Util.number import * import random def genPrime(): while True: a = random.getrandbits(256) b = random.getrandbits(256) if b % 3 == 0: continue p = a ** 2 + 3 * b ** 2 if p.bit_length() == 512 and p % 3 == 1 and isPrime(p): return p def add(P, Q,…