On the Subject of the Gridlock CM
A machine that knows no bounds when it comes to ciphers.
Create a key using the keyword on screen 1 and the Boolean Expression on screen A. Make sure to replace any Js with Is. Rearrange the key into a 5×5 matrix. This will be referred to as the Gridlock Key.
Take the digit string from screen 2 and place a cursor at the 1st digit.
For each letter of the encrypted word, do the following:
- 1: Start at the space that contains the Nth letter of the encrypted word in the Gridlock Key.
- 2: Repeat steps 3 - 6 until you reach a gridlock.
- 3: Mark the space that you're currently at.
- 4: Add the digits in the digit string at the cursor and to the right of the cursor, modulo 10. Append this digit to the digit string.
- 5: Take the digit at the cursor and turn it into an instruction via the Instruction Table. Move the cursor to the right 1 digit.
- 6: If the instruction tells you that you're in a gridlock, the current letter that you're on becomes your Nth decrypted letter.
- 7: Reset the Gridlock Key so that all the spaces become unmarked.
Finally, if any of the letters on screen 3 match at the same position as any of the letters of your decrypted word, replace that letter with a J. You should now have a decrypted word.