from logic import *
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AKnight = Symbol("A is a Knight")
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AKnave = Symbol("A is a Knave")
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BKnight = Symbol("B is a Knight")
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BKnave = Symbol("B is a Knave")
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CKnight = Symbol("C is a Knight")
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CKnave = Symbol("C is a Knave")
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# Puzzle 0
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# A says "I am both a knight and a knave."
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knowledge0 = And(
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Not(And(AKnave, AKnight)),
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Or(AKnave, AKnight),
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Implication(AKnight, And(AKnave, AKnight))
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)
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# Puzzle 1
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# A says "We are both knaves."
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# B says nothing.
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knowledge1 = And(
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Not(And(AKnave, AKnight)), Or(AKnave, AKnight),
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Not(And(BKnave, BKnight)), Or(BKnave, BKnight),
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Implication(AKnight, And(AKnave, BKnave)),
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Implication(AKnave, Not(And(AKnave, BKnave)))
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)
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# Puzzle 2
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# A says "We are the same kind."
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# B says "We are of different kinds."
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knowledge2 = And(
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Not(And(AKnave, AKnight)), Or(AKnave, AKnight),
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Not(And(BKnave, BKnight)), Or(BKnave, BKnight),
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Implication(AKnight, And(AKnight, BKnight)),
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Implication(BKnave, And(AKnight, BKnight)),
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Implication(BKnight, And(Not(And(BKnight, AKnight)), Not(And(BKnave, AKnave))))
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)
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# Puzzle 3
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# A says either "I am a knight." or "I am a knave.", but you don't know which.
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# B says "A said 'I am a knave'."
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# B says "C is a knave."
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# C says "A is a knight."
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knowledge3 = And(
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Not(And(AKnave, AKnight)), Or(AKnave, AKnight),
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Not(And(BKnave, BKnight)), Or(BKnave, BKnight),
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Not(And(CKnave, CKnight)), Or(CKnave, CKnight),
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Implication(AKnave, AKnight),
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Biconditional(AKnave, BKnight),
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Biconditional(BKnave, CKnight),
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Biconditional(AKnight, CKnight)
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)
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def main():
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symbols = [AKnight, AKnave, BKnight, BKnave, CKnight, CKnave]
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puzzles = [
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("Puzzle 0", knowledge0),
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("Puzzle 1", knowledge1),
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("Puzzle 2", knowledge2),
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("Puzzle 3", knowledge3)
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]
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for puzzle, knowledge in puzzles:
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print(puzzle)
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if len(knowledge.conjuncts) == 0:
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print(" Not yet implemented.")
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else:
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for symbol in symbols:
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if model_check(knowledge, symbol):
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print(f" {symbol}")
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if __name__ == "__main__":
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main()
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