45 lines
1.1 KiB
Markdown
45 lines
1.1 KiB
Markdown
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# Breadth First
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- Uniform cost with cost function proportional to depth
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- All of each layer
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- Max nodes before solution
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- $=1+b+b^2+b^3+b^4+...+b^n$
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- Time, space complexity = $O(b)^d$
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- Exponential
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- Lots of time but complete and optimal
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- Goal at depth, $d1$
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- $1+b+b^2+b^3+b^4+...+b^{d-1}=\frac{b^d-1}{b-1}$
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- Average at $\frac{1+b^d}{2}$ terminal nodes
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# Depth First
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- Between $(1+d)$ and $(\frac{b^{d+1}-1}{b-1})$
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- If at left hand side or right hand side
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- Much less memory space than BFS
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- Non-optimal, non-complete
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## Depth Limited
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- Predetermined max depth
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- Only complete if max depth is sufficiently large
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- Hard to determine
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# Bi-Directional
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- Out from start and goal until they meet
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- If done with heuristics
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- May not crossover
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# Iterative Deepening
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- Combine BFS and DFS
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