- Abstract
- Description on how the alpha-beta search works
- Animated version of alpha-beta search
- Static version of alpha-beta search

Researchers in game playing have developed a class of search techniques
called alpha-beta pruning to improve the efficiency of search in two person
games.
The idea for alpha-beta search is simple:-

- Alpha-beta search proceeds in a depth-first fashion rather than searching the entire space to the ply depth.
- Two values, called alpha and beta, are created during the search.
- The alpha value, associated with MAX nodes, can never decrease, and the beta value, associated with MIN nodes can never increase.

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Suppose a Max node's alpha value is 6. Then MAX need not consider any backed up value less than or equal to 6 that is associated with any MIN node below it. Alpha is the worst that MAX can score given that MIN will do its best. Similarily, if MIN has a beta value of 6, it need not consider any MAX node below it that has a value of 6 or more.

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This image represents the overview of the animated version of alhabeta search. |

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This image represents the state of the static version of alphabeta search |

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