28 lines
634 B
Markdown
28 lines
634 B
Markdown
# A\* Pathfinding
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There are 3 main values usedd in reference to A\*:
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```
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f = how promisiing a new location is
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g = distance from origin
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h = estimate distance to goal
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f = g + h
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```
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For a grid space our `h` is calculated by two straight shots to the goal from the current location(ignore barriers).
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The grid space `g` value is basiccally the number of steps we've taken from the origin.
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We maintain a list of potential nodes only, so if one of the seeking nodes gets us stuck we can freely remove that, because it succs.
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# Time & Space Commplexities
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## Best-First Search
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Time: O(VlogV + E)
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## Dijkstra's
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O(V)
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## A\*
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O(V^2 = E)
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