Edge-matching puzzle

An edge-matching puzzle is a type of tiling puzzle involving tiling an area with (typically regular) polygons whose edges are distinguished with colours or patterns, in such a way that the edges of adjacent tiles match.

Edge-matching puzzles are known to be NP-complete, and capable of conversion to and from equivalent jigsaw puzzles and polyomino packing puzzle.

The first edge-matching puzzles were patented in the U.S. by E. L. Thurston in 1892.

Current examples of commercial edge-matching puzzles include the Eternity II puzzle, TetraVex, Dodek Duo, Kadon Enterprises' range of edge-matching puzzles, and the Edge Match Puzzles iPhone app.

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