63 lines
1.1 KiB
Ruby
63 lines
1.1 KiB
Ruby
class Bot
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attr_reader :best_choice, :val
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def initialize board, piece
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@val = piece
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@piece = piece
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@opponent = switch piece
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end
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def move board
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minmax board, @piece
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board.set @piece, @best_choice
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end
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def minmax board, cur_player
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return score(board) if game_done?(board)
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scores = {}
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board.get_free.each do |space|
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# dup and clone only create a shallow clone, so it doesn't clone the array inside the board object.
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board.set cur_player, space
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scores[space] = minmax(board, switch(cur_player))
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board.remove space
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end
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@best_choice, best_score = best_choice cur_player, scores
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best_score
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end
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def switch cur
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cur == " X " ? " O " : " X "
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end
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def game_done? board
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board.any_winner? || board.is_full?
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end
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def best_choice piece, scores
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if piece == @piece then
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#p scores
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scores.max_by { |_k, v| v}
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else
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scores.min_by { |_k, v| v}
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end
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end
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def score board
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if board.is_winner? @piece
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return 10
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elsif board.is_winner? @opponent
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return -10
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end
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0
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end
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end
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