25 lines
460 B
Racket
25 lines
460 B
Racket
#lang plai
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(define-type Node
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(node (data string?) (adj list?)))
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(define g
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(shared ([PVD (node "Providence" (list ORH BOS))]
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[ORH (node "Worcester" (list PVD BOS))]
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[BOS (node "Boston" (list PVD ORH))])
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(list PVD ORH BOS)))
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g
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(define PVD (first g))
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(define ORH (second g))
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(define BOS (third g))
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PVD
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ORH
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BOS
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(test (node-adj PVD) (list ORH BOS))
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(test (node-adj ORH) (list PVD BOS))
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(test (node-adj BOS) (list PVD ORH))
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