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| • |
The following example demonstrating the A* search pattern is
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taken
from the course textbook (Artificial Intelligence : A
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Modern
Approach, Russell and Norvig, Prentice Hall, 1995,
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pages
95-99)
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| • |
If you are reading this book alongside your CIS 412 notes (and
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this
is strongly recommended) you may notice some minor
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differences.
For example, whereas in the book the authors
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expand ‘back’ to cities they have just come from, we ignore this
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in
order to make the animation a little clearer.
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Please note that this minor change does not affect the algorithm
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as
travelling to a city and then travelling back to where you
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have just come from is not going to be included in the optimal
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solution.
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| • |
One other small point about the course textbook. Figure 4.4
on
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page 98 has a minor error (at least, it certainly does in the 1995
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edition). The expansion of Sibiu to Oradea reads 146 + 380 =
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526. It should read 291
+ 380 = 671. Fortunately, this error
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makes
no difference to the way the algorithm operates.
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