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>> Now that you've initialized the board,
and that you've drawn it, it's time to

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let the user edit it and
make their moves.

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So in that 15.c function, the program
takes input from the user and then

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calls the move function, passing in the
number of the tile that the user

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wants to move.

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Now be careful.

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This is the actual number of the tile
and not its actual position.

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So you'll need to search for the tile's
position to know where it is.

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>> Now, you should only allow the user
to make a move if it's legal.

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A legal move is any tile that is
adjacent to the blank tile.

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That means above and below, to
the left and to the right.

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So you'll need to know where
the blank tile is as well.

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>> Now, for every move, you're searching
for the user's tile.

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00:00:47,400 --> 00:00:51,560
But it's probably not best to search for
the blank tile every time, because

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you're doing it every single time
the user wants to move.

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So instead, it's best to remember where
the blank tile is, using some

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well named variables.

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So once you allow the user to make their
moves, they are well on their

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way to winning the game of 15.

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