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README.md

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+# Automated Cipher Cracking
+
+This code implements the Caesar, Vigenere and substitution ciphers and automatically decrypts text written in them.
+[Katz's backoff model](https://en.wikipedia.org/wiki/Katz%27s_back-off_model) is used to score candidate decryptions.
+The Caesar cipher is can be brute forced easily, but the Vigenere and substitution ciphers use simulated annealing to find a solution.
+
+This was a prototype to investigate the feasibility of [UTEK 2018's programming challenge](https://github.com/utek-2018/competition-package), hence the simplicity.
+
+## Example
+```
+DWQI IOKDOKTO QI L ELQZJY DYBQTLJ GKO LKU IWGSJU VO OLIY DG UOTZYBD. -> 
+LVTUOE*WQ**J*KGB*ZIDS***Y* | THIS SENTENCE IS A FAIRLY TYPICAL ONE AND SHOULD BE EASY TO DECRYPT.
+```
+
+## Notes
+* For the Caesar and Vigenere ciphers, surprisingly little training data is needed. 
+For the Caesar cipher, a few lines of text was enough. For the Vigenere cipher, a couple paragraphs sufficed.
+* Seeding the substitution cipher with a frequency attack didn't help much.
+
+## Possible Improvements
+* Optimize hyperparameters (number of iterations, speed of temperature drop)
+* Try heuristic-based search: weight decrypting common letters in the ciphertext as common letters in English
+* Try more organized search: swap keys from sequential indices instead of randomly
+* Improve the model: use a dictionary, neural network etc.
+
+## Running
+Expects test cases in the `input` folder and writes to the `output` folder. 
+
+```
+npm install
+git clone https://github.com/utek-2018/competition-package
+python3 competition-package/tester.py --ref=competition-package/
+```