2001 Paper 9 Question 8
Artificial Intelligence
(a) Why does search in game-playing programs always proceed forward from the
current position rather than backward from the goal? [5 marks]
(b) Most game-playing programs do not save search results from one move to the
next. Instead, they usually start completely afresh whenever it is the machine’s
turn to move. Why? [5 marks]
(c) Consider the following game tree, and assume that the first player is the
maximising player:
A
B C D
E F G H I J K
L M N O P Q R S T U V W X Y
2 3 8 5 7 6 0 1 5 2 8 4 10 2
(i) Which move should the first player choose? [3 marks]
(ii) Assuming that nodes are searched left-to-right using the alpha-beta
algorithm, which nodes would not be examined? [7 marks]