05_uninformed_search2013

# 11 seconds memory 1 megabyte 4 111100 11 seconds 106

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Unformatted text preview: mallest instances. Total number of nodes expanded: b + b 2 + b 3 + ... + b d + (b d +1 − b) = O(b d +1 ) n༆  BFS evaluation Does it always find the least-cost solution? In general YES DEPTH NODES TIME 2 1100 0.11 seconds MEMORY 1 megabyte 4 111100 11 seconds 106 megabytes 6 107 19 minutes 10 gigabytes 8 109 31 hours 1 terabyte 10 1011 129 days 101 terabytes 12 1013 35 years 10 petabytes 14 1015 3523 years 1 exabyte Time and memory requirements for BFS for b=10, 10,000 nodes/sec; 1000 bytes/node 6 9/20/13 Uniform cost search n༆  n༆  Extension of BFS: q༇  n༆  Uniform cost search Expand node with lowest path cost Implementation: frontier= queue ordered by path cost. Completeness: n༆  Time complexity: q༇  q༇  q༇  n༆  q༇  Same as BFS when all step-costs are equal. YES, if step-cost > ε (smal positive constant) Assume C* the cost of the optimal solution. Assume that every acti...
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## This note was uploaded on 02/10/2014 for the course CS 440 taught by Professor Staff during the Fall '08 term at Colorado State.

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