-def monoalphabetic_break_hillclimbing(message, max_iterations = 10000000,
- fitness=Pletters):
- ciphertext = unaccent(message).lower()
- alphabet = list(string.ascii_lowercase)
- random.shuffle(alphabet)
- alphabet = ''.join(alphabet)
- return monoalphabetic_break_hillclimbing_worker(ciphertext, alphabet,
- max_iterations, fitness)
-
-def monoalphabetic_break_hillclimbing_mp(message, workers=100,
- max_iterations = 10000000, fitness=Pletters, chunksize=1):
- worker_args = []
- ciphertext = unaccent(message).lower()
- for i in range(workers):
- alphabet = list(string.ascii_lowercase)
- random.shuffle(alphabet)
- alphabet = ''.join(alphabet)
- worker_args.append((ciphertext, alphabet, max_iterations, fitness))
- with Pool() as pool:
- breaks = pool.starmap(monoalphabetic_break_hillclimbing_worker,
- worker_args, chunksize)
- return max(breaks, key=lambda k: k[1])
-
-def monoalphabetic_break_hillclimbing_worker(message, alphabet,
- max_iterations, fitness):
- def swap(letters, i, j):
- if i > j:
- i, j = j, i
- if i == j:
- return letters
- else:
- return letters[:i] + letters[j] + letters[i+1:j] + letters[i] + letters[j+1:]
- best_alphabet = alphabet
- best_fitness = float('-inf')
- for i in range(max_iterations):
- alphabet = swap(alphabet, random.randrange(26), random.randrange(26))
- cipher_translation = ''.maketrans(string.ascii_lowercase, alphabet)
- plaintext = message.translate(cipher_translation)
- if fitness(plaintext) > best_fitness:
- best_fitness = fitness(plaintext)
- best_alphabet = alphabet
- print(i, best_alphabet, best_fitness, plaintext)
- return best_alphabet, best_fitness
-
-