An edge-matching puzzle is a type of tiling puzzle

Tiling puzzle

Tiling puzzles are puzzles involving two-dimensional packing problems in which a number of flat shapes have to be assembled into a larger given shape without overlaps . Some tiling puzzles ask you to dissect a given shape first and then rearrange the pieces into another shape...

 involving tiling an area with (typically regular) polygon

Polygon

In geometry a polygon is a flat shape consisting of straight lines that are joined to form a closed chain orcircuit.A polygon is traditionally a plane figure that is bounded by a closed path, composed of a finite sequence of straight line segments...

s 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

NP-complete

In computational complexity theory, the complexity class NP-complete is a class of decision problems. A decision problem L is NP-complete if it is in the set of NP problems so that any given solution to the decision problem can be verified in polynomial time, and also in the set of NP-hard...

, and capable of conversion to and from equivalent jigsaw puzzle

Jigsaw puzzle

A jigsaw puzzle is a tiling puzzle that requires the assembly of numerous small, often oddly shaped, interlocking and tessellating pieces.Each piece usually has a small part of a picture on it; when complete, a jigsaw puzzle produces a complete picture...

s 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

Eternity II puzzle

The Eternity II puzzle, aka E2 or E II, is a puzzle competition which was released on 28 July 2007.The competition ended at noon on the 31st of December 2010.It was published by Christopher Monckton, and is marketed and copyrighted by TOMY UK Ltd...

, TetraVex

TetraVex

TetraVex is a puzzle computer game, available for Windows and Linux systems.- Gameplay :TetraVex is an edge-matching puzzle. The player is presented with a grid and nine square tiles, each with a number on each edge. The objective of the game is to place the tiles in the grid in the proper...

, Dodek Duo, Kadon Enterprises' range of edge-matching puzzles, and the Edge Match Puzzles iPhone app.

External links

• Erich's Matching Puzzles Collection
• Color- and Edge-Matching Polygons by Peter Esser
• Rob's puzzle page by Rob Stegmann