29 lines
417 B
Racket
29 lines
417 B
Racket
#lang datalog/sexp
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(! (parent john douglas))
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(? (parent john douglas))
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(? (parent john ebbon))
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(! (parent bob john))
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(! (parent ebbon bob))
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(? (parent ,A ,B))
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(? (parent john ,B))
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(? (parent ,A ,A))
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(:- (ancestor ,A ,B)
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(parent ,A ,B))
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(:- (ancestor ,A ,B)
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(parent ,A ,C)
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(ancestor ,C ,B))
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(? (ancestor ,A ,B))
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(? (ancestor ,X john))
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(~ (parent bob john))
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(? (parent ,A ,B))
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(? (ancestor ,A ,B))
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