13 lines
219 B
Racket
13 lines
219 B
Racket
#lang datalog/sexp
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; path test from Chen & Warren
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(! (edge a b))
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(! (edge b c))
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(! (edge c d))
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(! (edge d a))
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(! (:- (path X Y)
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(edge X Y)))
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(! (:- (path X Y)
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(path X Z)
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(edge Z Y)))
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(? (path X Y))
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