- Python 3.7+
- z3:
pip install z3-solver
python3 solver.py- Paste Taiji Maker puzzle code and press enter
- May take a while (few minutes for medium sized puzzles, probably much longer for large ones)
- Each cell has a z3 Bool to determine whether it's on or off and a z3 Int to determin the area it's in
- Flowers are trivial: Constrain that number of neighbors with n.lit != flower.lit is equal to the yellow petals
- For everything else we need areas:
- For all neighboring cells, enforce a.area == b.area <=> a.lit == b.lit
- But this allows disconnected areas getting assigned the same number i.e. being considered the same
- To solve this, we create a z3 Int for number of areas
- Constrained by Euler characteristic (vertecies - edges + faces = 1)
- Put vertex at each cell corner along an area border
- Number of edges: sum of neighboring cell pairs where a.lit != b.lit + fixed number of edges towards the outside
- Number of vertecies: similar but instead check for each corner if any of the four neighboring cells that share a border don't have the same state
- Then we can enforce that there exist that many different area values (or rather, that there exists at least one cell with each area value from 0 to the number of areas) which automatically enforces that each area has a unique number
- For dice:
- Now trivial: constrain that for each region the number of cells in it equals the number of dice pips
- If different colored dice exist, also define a z3 function f that assigns each area a color (just an int, corresponding to the index of the color) and enforce that f(dice.area) == dice.color for all dice
- For diamonds:
- Now also trivial: enforce that the number of cells with the same color and area as the diamond equals one
- The method to represent areas is based on ideas from the blog post Solving The Witness with Z3
- And ofc this is only possible due to the amazing z3 prover