Candy Crush Helper

I was listening to Tim Ferris interview Jane McGonigal on the neuro-programming that occurs around playing games.  One of the games mentioned was Candy Crush Saga.  Curious, I decided to start playing it – and now I find it relaxing, a good place to put my mind when my mind is obsessing about other things.

But of course, being me, I started to wonder, “can I program a solution for this?”    Well, of course not – the boards are actually random – but I could write a helper to detect available moves, and possibly future moves.

Turns out a guy already wrote one.  See his video explaining how it works here.   However, I couldn’t get it to run, and it required me running candy crush on my laptop.  And, it didn’t look ahead moves – just the currently available ones.  Still, an impressive piece of work. 

2015-09-12 22.36.39So I started coding one for fun.   I started with this screen:

Question:  How many possible moves do you see?  (A move for the uninitiated, is swapping adjacent candies so they form at least 3 in a row or 3 in a column).  I counted 11 on my initial count.

I wrote some code to load this into a class, and wrote some methods to load candies.   It was a very zen-kata-exercise thing to figure out how to save the board – turns out I didn’t know 2D arrays in C# very well at all (and I still don’t, I chose a different method): image
I wrote a some “possible candy swap” code, and wrote some stuff to find solutions, and wrapped that in a test: image
It says there are 14 moves. What?  I don’t have a clean way of outputting the moves yet, so I will have to highlight them by hand. image (89 ms)

Here’s what it found: 


  • Yeah. Bug in my code.  I thought I was doing a copy from one board to another, but it was a shallow copy, so all the “possible” moves were being remembered one after the other, rather than one at a time.  PANDA-MONIUM!

My attempted fix of the code didn’t work.   And its getting late.

I believe the test needs to Assert(13, allPossibleMoves.Count):


Or am I missing something?   I will resume this.. some day. 

In the mean time, it raises interesting things like:

  • How to represent a very complicated system in a way that makes sense while developing?
  • How to load test data into complicated systems?

Happy crushes.  I’m at level 35, FWIW.

Oh, and I’m using the test-adapter to run NUnit Tests using Microsoft’s test-running tools.