57. I got a ton of shape rotation problems. Figured out a strategy for those:
Focus on the 3 pronged shape. It is unique in all 4 orientations. You can use this to filter out bad rotations. Then use adjacencies to filer out the rest.
Focus on the 3 pronged shape. It is unique in all 4 orientations. You can use this to filter out bad rotations. Then use adjacencies to filer out the rest.