README

SIMPLE DECIPHER PROJECT
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This software tries to solve the problem of deciphering a simple
substitution ciphered text with no spaces.

This project was born from a capture the flag game proposed by an
IT Security teacher at the university. The game is about choosing
a 1000 letters text and ciphering it with the simple substitution
algorithm.

For long texts CrypTool makes it simple to decipher by letter
statistics. For small ones there are various online tools to
easily solve it, but only when the text is normally spaced.
When no spaces are leaved, deciphering a small text becomes
harder.

This tool makes the following steps to decipher the text:
    1. Two small pieces of ciphered text are passed as arguments
    2. All possible words patterns are extracted form the pieces
    3. Every pattern is matched with all possible dictionary words
    4. A tree search algorithm its performed on each piece
    5. Both sets of solutions generated are compared and the most
       similar couple is chosen as the probable solution