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We start our in-depth tour of general game
playing by looking at single player games.

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Such as Sudoku, or sliding tile puzzles,
Rubik's cube, and so forth.

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In the game playing community, these are
often called puzzles, rather than games.

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And the process of solving such puzzles is

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often called problem solving rather than
game playing.

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Puzzles are simpler

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than multiple player games because
everything's

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under the control of a single player.

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World static, except when the player acts,
and changes to the world

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are determined entirely by the current
state and the actions of the player.

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In this lesson, as in most of the course
we

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assume that the player has complete
information abut the puzzle.

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Assume that it knows the initial state.

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You know that, it knows its legal actions
in every state.

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It knows the effects of its actions in
every state.

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For every state, it knows its reward, and
for

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every state, it knows whether or not it's
terminal.

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In this lesson, we also assume the games
are small.

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That is the player has sufficient space
and time to search the entire game tree.

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This guarantees that the player can find
optimal actions to perform.

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Now that said, as we'll see, it's
sometimes possible to

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find optimal actions even without
searching the entire game tree.

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Despite these strong assumptions, just one
player, complete information,

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availability of adequate time to search
the game tree.

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The study of single player games is a good

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place to start our look at general game
playing.

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First of all, many real world problems can
be

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cast as single player games with these
same restrictions.

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Su, such as finding possible protein

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foldings as suggested by the illustration
here.

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[COUGH]

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More importantly for us, as we'll see.

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The techniques we examine later can be
viewed as

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more elaborate versions of the basic
techniques introduced here.