2. Hactar
3. android app - go
4. English
5. Zen

Go Rules

The game starts from an empty board, and black plays the first stone. The goal is to surround empty territory and capture opponents stones. Game ends when both players pass. Stones can be captured in the same way as in capture-go. Repetition of same board position is forbidden similarly to capture 3 game.

Game End

When a player does not want to play, he passes. The game ends with two consecutive passes.

Calculating Result

After the game ends, a result is calculated. Any stones that opponent could capture are calculated as captured. Players points are the sum of following: * The territory he has surrounded, * Captured and capturable opponents' stones. White usually gets some extra compensation for blacks' right to start the game. This is called komi. Hactar uses Japanese rules for calculating result.

Even Games and Handicap Games

In an even game white gets 6.5 extra points to compensate black's right to start the game. If black player is less skilled than white, a handicap can be used to make the game interesting. Black player may get 2 to 9 handicap stones at the start of the game. In a handicap game white gets 0.5 extra points (komi).

This game has ended. White has a komi of 6.5 points. Neither player has captured stones. Sizes of different areas in board are shown. Black has 18 points. White has 23.5 points (17 in board and 6.5 komi). So white wins 5.5 points.

Simple Example

The territory sizes are marked into the board. White gets 6.5 point compensation. Black has captured 4 white stones, and two white stones in board (a) are also dead. White has captured 2 black stones (not visible in diagram). Black has 19 points. White has 20.5 points.

Complete Example

When the game has ended?

Close to end of the game it may be difficult see where moves could still gain points.

In following problems you need to identify last remaining place, where points could be gained, or reduced. The gained points are marked in the correct answer. The lost reduction opportunities are marked in wrong variations.