When trying to avoid conflict and maintain peace, a good strategy is to remove the elements that cause the most trouble. IBM is using its Deep Blue machine to try to study this strategy by modeling it with a game of chess. IBM needs a program to find the minimum number of chess pieces that must be removed from a chessboard in order for none of the pieces to be attacking each other.
All pieces will have the standard attack movements for that chess piece.
King - Can attack the adjacent space in any direction. Up, down, left, right and diagonally.
Queen - Can attack any number of spaces in any direction. Up, down, left, right and diagonally.
Bishop - Can attack any number of spaces diagonally.
Rook - Can attack any number of spaces up, down, left, or right but not diagonally.
Pawns - There won't be any pawns.
Knight - Can attack with their usual 'L' shaped movement. Up twice and right once, up once and left twice, etc... Here is a diagram, which demonstrates the movement of a knight.
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| | |*| |*| | |
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| |*| | | |*| |
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| | | |N| | | |
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| |*| | | |*| |
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| | |*| |*| | |
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N = Knight
* = Square that the knight can attack