Classic Computer Magazine Archive ANTIC VOL. 4, NO. 3 / JULY 1985


Automatic "blackboard" for codebreaking


Now your Atari can remove a lot of erasing and tedium from solving code puzzles.  Every time you enter a substitute letter, you'll get a global replacement throughout the secret message.  This BASIC program works on all Atari computers of any memory size, with disk or cassette.

I'm a cryptoquote fan. I love to work over these nonsense letter groups trying to find their hidden meaning. You find cryptoquote word puzzles in many newspapers. They are sayings that have had their letters substituted with other letters. Let's say the word "THAT" appears as WFRW; the W stands for T, F for H, and R for A. You try to break the code and find out what the puzzle really says.
   Solving cryptoquotes requires trying lots of letter combinations, and this means using lots of paper-or using this program.

To solve these codes, you look for clues in the letter combinations and word groups. When you think you know what one word is, you write that word above its corresponding code letters. You then write those letters above their encoded counterparts throughout the rest of the cryptoquote.
   If your word seemed to show that the letter W in the cryptoquote was really the letter T, you would search for every W and replace it with a T. This process then leads you to other clues, or to a conclusion that your guess was wrong.

Type in Listing 1, Check it with TYPO II and SAVE a copy It will function as an automatic blackboard, looking for the letters and erasing entries.
   You'll be asked to type in the cryptoquote, which will be displayed in in-verse letters. To enter a guess, type the letter you want to change, a space and the letter you want to replace it with. The program will place your guessed letter above the letter to be changed. To erase a guess, type the cryptogram letter corresponding to the guess you want erased.
   If you like this program, here are some modification ideas that you might try to work out.

   1. Check the input to see if the letter you want as a replacement has been already used.

   2. Allow for input of entire letter groups at a time, instead of single letter input.

   3. Have the punctuation copied automatically to the replacement line.

   4. Speed up the program.

   5. Make a game out of the puzzle by installing a counter-try to solve the cryptoquote in as few moves as possible. Have the computer calculate the minimum possible moves.

   I'll say goodbye with a cryptogram:


Hint: Y is a T. Good luck.

Mike Fleischmann is a professional programmer and digital design engineer from Sunset, Utah. His contributions to Antic include our current listing printout program.

Listing 1   CRYPTO.BAS Download