State-space complexity refers to the number of different game-positions that can exist in a game. Game-tree complexity is normally defined as the product of the games average branching factor and the number of plies (half-moves) in an average game. The game-tree complexity is normally higher than the state space complexity due to the fact that the same position can occur in multiple games.
Due to the large size of these complexities often their logarithms (base 10) are given instead of their actual value.
Game | State-space | Game Tree |
---|---|---|
Nine Men's Morris | 10 | 50 |
Awari | 12 | 32 |
Pentominoes | 12 | 18 |
Connect Four | 14 | 21 |
Backgammon | 20 | 144 |
Checkers | 21 | 31 |
Lines of Action | 24 | 56 |
Othello | 28 | 58 |
Chess | 46 | 123 |
Shogi | 71 | 226 |
Go | 172 | 360 |
See also: Solved board games