Numberlink

Arukone (Japaneseアルコネ) or Nanbarinku (Japaneseナンバー リンク) is a Japanese logic puzzle that was first published by the Japanese magazine Nikoli.

Arukone is also known by other names, including: Number Link, Connection alphabet, ABC Connection and letters covenant.

Regulate

Arukone is played on a rectangular grid of squares of any size. On some fields letters are given. The aim of the game is so to connect all fields with letters to each other that the following rules apply:

• All fields with the same letter must be connected by a single, continuous line.
• At each field with a letter starts or ends exactly one line.
• The individual sections of a polyline extend either horizontally or vertically.
• Each field must contain only part of a single continuous line and in particular line trains do not cross each.

Moreover, it is common to specify characters in alphabetical order. Sometimes numbers instead of letters are used. The rules are then accordingly.

Normally, the solution through the specified letters or numbers is clearly defined.

Variants

Sometimes the rule is added to the above rules still taken that each field must contain exactly one part of a polyline, ie, that no field is allowed to remain free in solution.

Solution strategies

To solve a Arukone one usually tries to gradually separate letters to connect with each other, which are then given to the sought solution.

So there is sometimes (as in the example on the left ) for the connection of two letters at all and only one way, which then must pass that way. Other line segments between two different letters can be excluded by the fact that there will be absolutely no more trace of another letter pair.

By logical considerations, a number of other solution Strategieen can specify which ultimately lead to the desired solution.