PDS-PN: A New Proof-Number Search Algorithm
نویسندگان
چکیده
The paper introduces a new proof-number (PN) search algorithm, called PDS-PN. It is a two-level search, which performs at the first level a depth-first Proof-number and Disproof-number Search (PDS), and at the second level a best-first PN search. First, we thoroughly investigate four established algorithms in the domain of LOA endgame positions: PN, PN, PDS and αβ search. It turns out that PN and PDS are best in solving hard problems when measured by the number of solutions and the solution time. However, each of those two has a practical disadvantage: PN is restricted by the working memory, and PDS is relatively slow in searching. Then we formulate our new algorithm by selectively using the power of each one, viz. the two-level nature and the depth-first traversal respectively. Experiments reveal that PDS-PN is competitive with PDS in terms of speed and with PN since it is not restricted in working memory.
منابع مشابه
An effective two-level proof-number search algorithm
The paper presents a new proof-number (PN) search algorithm, called PDS-PN. It is a two-level search (like PN), which performs at the first level a depth-first Proof-number and Disproof-number Search (PDS), and at the second level a bestfirst PN search. Hence, PDS-PN selectively exploits the power of both PN and PDS. Experiments in the domain of Lines of Action are performed. They show that wit...
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