Hill Climbing Vigenere Cipher Breaker

Usage

• cd to the directory with the script
• Run julia. All the following commands should be used in the REPL.

To encode text

• plaintext = preprocess_text("""text_here""")
• vigenere_encode(plaintext, "key_here")

To decode text

• ciphertext = """ciphertext_here""" The encoding preferably should have skipped over punctuation.
• vigenere_encode(plaintext, "key_here", true)

To crack text

• ciphertext = """ciphertext_here""" The encoding preferably should have skipped over punctuation.
• cracked_keys = crack_key(ciphertext, 30, 0.15, 5, 50, 0.1)
  • Parameters, from left to right, are:
    • Max key length: The upper bound on the key length.
    • Epsilon: The chance that the algorithm explores nonoptimal choices. Increase this to encourage exploration.
    • Epochs: How many times the algorithm should restart. Each restart generates a new key.
    • Decay: A constant to multiply the epsilon by every cycle. Smaller values will result in faster decay. This is for simulating annealing.
  • The keys, along with their "scores", will be printed.
  • The keys will also be returned as an array of strings (duplicates will be removed).
• display_cracked_texts(ciphertext, cracked_keys) to view the results of the key.