The official round of thing-a-day is done. Thank you all for your incredible work and see you next year!

1 Vote up

Day eighteen: (incomplete) Subsititution Cypher Solver

Today I re-started work on a program to solve substitution cyphers. The substitution cypher is where you take every character in your message and replace it with a different character- they sell little puzzle books full of these to try and crack by hand. My (most likely naive) approach for doing this is to count the frequency of each letter in the message. Starting with a list of the letters that occur most frequently in the English language, I will then use a bunch of different substitution combinations to decrypt the message and compare against a dictionary to calculate which combination works best. It would be ugly to search all combinations because there are so many, so I will start off by masking out all of the letters I haven’t found yet. The code doesn’t get far, but demonstrates how to load the files in.

Last 5 posts by cibomahto

Comments:

Leave a comment:

  • *Required
  • *Required (never published)
  • *
    To prove you're a person (not a spam script), type the security word shown in the picture. Click on the picture to hear an audio file of the word.
    Click to hear an audio file of the anti-spam word