Islands - Hashi puzzle

哈希之谜：放松并训练你的大脑。

This puzzle game is based on Hashiwokakero, a logic game published by the Japanese Nikoli.

It has also been published in English under the name Bridges or Chopsticks (based on a mistranslation: the hashi of the title, 橋, means bridge; hashi written with another character, 箸, means chopsticks). It has also appeared in The Times under the name Hashi. In France, Denmark, the Netherlands, and Belgium it is published under the name Ai-Ki-Ai.

The goal is to connect all of the islands by drawing a series of bridges between the islands. The bridges must follow the following criteria:

* The number of bridges connected to each island must match the number on that island.

* Islands can be connected with at most two bridges.

* They may only run orthogonally (i.e. they may not run diagonally).

* They must not cross any other bridges or islands.

* The bridges must connect the islands into a single connected group.