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authorJ.J <thechairman@thechairman.info>2023-11-30 17:10:00 -0500
committerJ.J <thechairman@thechairman.info>2023-11-30 17:10:00 -0500
commit8ab65dc2da1742eb86ec636c50c7018385b68167 (patch)
treec4fd556aca9b867cfa1f2f174128c30857353884 /2020/day-11
parentfafbeaf9e3c09ba7a5bea7e47d5736001f8a5aa1 (diff)
downloadgleam_aoc-8ab65dc2da1742eb86ec636c50c7018385b68167.tar.gz
gleam_aoc-8ab65dc2da1742eb86ec636c50c7018385b68167.zip
prep for 2023, renaming for consistency
Diffstat (limited to '2020/day-11')
-rw-r--r--2020/day-11/day-11.rkt60
1 files changed, 0 insertions, 60 deletions
diff --git a/2020/day-11/day-11.rkt b/2020/day-11/day-11.rkt
deleted file mode 100644
index e2fe052..0000000
--- a/2020/day-11/day-11.rkt
+++ /dev/null
@@ -1,60 +0,0 @@
-#lang racket
-
-(require advent-of-code)
-
-(define raw-grid (fetch-aoc-input (find-session) 2020 11))
-
-(define/match (parse _)
- [(#\L) 'empty]
- [(#\#) 'occupied]
- [(#\.) 'floor])
-
-(define seat-grid
- (for*/hash ([(row r) (in-indexed (in-list (string-split raw-grid)))]
- [(col c) (in-indexed (in-string row))])
- (values (cons r c) (parse col))))
-
-(define (next-seat-state seat state h rule [max-occupy 4])
- (define neighbor-states (rule seat h))
- (match* (state (count (curry eq? 'occupied) neighbor-states))
- [('empty 0) 'occupied]
- [('occupied n)
- #:when (>= n max-occupy)
- 'empty]
- [(_ _) state]))
-
-(define (stabilize h [i 1] #:rule rule #:max-occupy [max-occupy 4])
- (define h*
- (for/hash ([(seat state) (in-hash h)])
- (cond
- [(eq? state 'floor) (values seat state)]
- [else (values seat (next-seat-state seat state h rule max-occupy))])))
- (if (equal? h h*)
- (count (curry equal? 'occupied) (hash-values h))
- (stabilize h* (add1 i) #:rule rule #:max-occupy max-occupy)))
-
-;; part 1
-(define (find-nearest-neighbors p h)
- (match-define (cons r c) p)
- (for*/list ([r* (in-inclusive-range (sub1 r) (add1 r))]
- [c* (in-inclusive-range (sub1 c) (add1 c))]
- [p* (in-value (cons r* c*))]
- #:unless (equal? p p*))
- (hash-ref h p* 'out-of-bounds)))
-
-(stabilize seat-grid #:rule find-nearest-neighbors)
-
-;; part 2
-(define (find-visible-neighbors p h)
- (match-define (cons r c) p)
- (define directions
- (for*/list ([dr '(-1 0 1)] [dc '(-1 0 1)] #:unless (= 0 dr dc))
- (cons dr dc)))
- (for/list ([dir (in-list directions)] #:do [(match-define (cons dr dc) dir)])
- (for*/first ([i (in-naturals 1)]
- #:do [(define p* (cons (+ r (* i dr)) (+ c (* i dc))))
- (define state (hash-ref h p* 'out-of-bounds))]
- #:unless (equal? state 'floor))
- state)))
-
-(stabilize seat-grid #:rule find-visible-neighbors #:max-occupy 5)