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Day 19: Forgot to revert experimental changes.

This commit is contained in:
Jonathan Chan 2021-12-19 21:54:09 -08:00
parent 8e6e0dcfcd
commit e5c9bddeb3
1 changed files with 8 additions and 14 deletions
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22
src/19.rkt
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@ -26,11 +26,6 @@
(match-let ([(list x y z) change]) (match-let ([(list x y z) change])
(+ (abs x) (abs y) (abs z)))) (+ (abs x) (abs y) (abs z))))
(define (deltas region)
(for*/set ([beacon1 region]
[beacon2 region])
(abs (magnitude (delta beacon1 beacon2)))))
(define rotations (define rotations
(for*/fold ([rotations '()]) (for*/fold ([rotations '()])
([dx '(1 -1)] ([dx '(1 -1)]
@ -51,15 +46,14 @@
(values region (map #{set-map region %} rotations)))) (values region (map #{set-map region %} rotations))))
(define (combine region1 region2) (define (combine region1 region2)
(and (>= (set-count (set-intersect (deltas region1) (deltas region2))) 66) (for*/or ([beacon1 region1]
(for*/or ([beacon1 region1] [beacon2 region2])
[beacon2 region2]) (define change (delta beacon1 beacon2))
(define change (delta beacon1 beacon2)) (define shifted-region2
(define shifted-region2 (set-map region2 #{shift % (delta beacon1 beacon2)}))
(set-map region2 #{shift % (delta beacon1 beacon2)})) (and (>= (set-count (set-intersect region1 shifted-region2)) 12)
(and (>= (set-count (set-intersect region1 shifted-region2)) 12) (cons (set-union region1 shifted-region2)
(cons (set-union region1 shifted-region2) change))))
change)))))
(define-values (part1 part2) (define-values (part1 part2)
(time (time