This is a ruby project to solve the first 2015 GCHQ Christmas puzzle
The image in puzzle.png shows the starting grid and patterns
To run the solution:
- clone the project
- cd into project directory
- run
ruby bin/un_puzzle.rb
Output should look like this:
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Solved !!
If you want to see more output, set debug to true in bin/un_puzzle.rb
Update: Fixed partial solution loop
The code isn't multi-threaded, and there are probably a whole bunch of optimisations to be made, but it solves this particular puzzle in ~4 seconds
The error handling isn't bulletproof
The code should be able to solve any grid of any size (given enough time :)) as long as the grid is encoded in the same way (i.e. using the patterns of filled-in sections)
The patterns and pre-filled cells are all stored in puzzle.yml so feel free to play
This code won't solve the puzzle if you omit the pre-filled cells and just start with an empty grid. In order to solve the puzzle in this case (and therefore be a complete solution for all puzzles), the code would need to create and traverse some kind of solutions tree, where it guesses a solution and tries to solve the puzzle, pruning all branches that result in an invalid solution