1、附录 附录 A： A Introduction About Chinese Chess SomeMajor Differences Between Chinese Chess And Western Chess Are As Follows. 1. Western chess is played on an 88 board with six different kinds of pieces, while Chinese chess is played on a 910 board with seven different kinds of pieces. The Chinese chess
2、board is more difficult to represent on a computer. 2. The board of Chinese chess is more like a “battlefield” than a chessboard is. The Chinese chessboard has two special territories. One is the Palace. The Kings and Advisors can move only within their Palace. The other is the River. Elephants cann
3、ot cross the River. These constraints seem to reduce the complexity of Chinese chess, since these pieces at first may appear not to be able to threaten pieces on the other side of the River, but this is a fallacy. These pieces can, in fact, directly threaten the other sides pieces by being a Cannons
4、 mount and by the special rule that Kings should avoid seeing each other face to face. 3. Cannons are very special pieces. Cannons move like Rooks but have to jump over piece to capture it. Thus, any piece co-operating with Cannons will have the same power as a Rook. Western chess has no similar pie
5、ce. 4. Although Kings cannot leave the Palace, Chinese chess has a special rule that allows them to threaten their counterparts: Kings may not see each other face to face. Based on this rule, Kings sometimes have a power similar to that of Rooks, which is very useful in the endgame stage. 5. Blockin
6、g rules apply to Elephants and Horses. Western chess has no similar rule. 6. Pawns move one space at a time. When a Pawn reaches the opposite bottom line, it cannot be turned into another piece as it can be in Western chess. 7. Repetitive situations are relatively simple in Western chess. In Chinese
7、 chess, however, because of the larger board and the characteristics of certain pieces, repeating situations in which neither side wants to make a concession, is more likely to arise. Special rules are required to govern these situations. In some extreme situations, a referee must make a judgement.
8、Therefore, resolving repeating situations is a challenge in computer Chinese chess. Quiescent Search A quiescence search explores all captures and checks from the current position, terminating at quiescentpositions, defined as those in which no captures or checks are available. Processing Perpetual
9、Situations As we described, perpetual situations have to be identified during the search process. The influence of a check effect happens frequently. If theprogramonlyassesses at the first level, it may leads to a wrong board status that repeatedly tries to kill the King. Computing AndStoring The Re
10、sults In Advance When the opponent is thinking, the program could make use of this “free time” to predict the opponents move and store the results. If the prediction is right, the results are fetched without further computation. Forward Pruning This includes razoring, futility pruning, and null move. Move Ordering This includes killer heuristic, history heuristic (Schaeffer, 1983), and internal iterative deepening. Transposition Table
