Draw a single continuous loop by connecting neighboring dots along the dotted lines. The numbers indicate how many edges of a cell are used for the loop. The loop may not touch or cross itself, and it doesn't need to touch all of the dots.
Many of the following variants can be combined.
- Fences can be converted to almost every planar Graph. Usually regular shapes are used. The most common variants are hexagons, triangles and rectangular with "holes".
- The numbers give the number of neighbouring corners, that bent 90°.
- The diagram is divided into white an gray fields. One of the colors denote correct numbers, the other wrong numbers.
- Cryptoversion: The numbers have been replaced with letters.
- Degrees: Instead of the numbers in the fields, there are numbers given in the grid points, that denote the angle of the path.
The fences puzzle has been published first by Nikoli. It is said, that it is a derivative of a game, that has been played on the Go-board, where now closed paths are allowed.