From 61f870ddac2fe97e8ef1f108d6f6a6aa0d6d8a28 Mon Sep 17 00:00:00 2001
From: haskal <haskal@awoo.systems>
Date: Thu, 17 Dec 2020 00:17:44 -0500
Subject: [PATCH] day 17: awful submission lol

---
 17.rkt | 98 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100644 17.rkt

diff --git a/17.rkt b/17.rkt
new file mode 100644
index 0000000..bdb9499
--- /dev/null
+++ b/17.rkt
@@ -0,0 +1,98 @@
+#lang curly-fn racket
+
+(require "scripts/aoc.rkt")
+
+;; solution for day 17
+
+(struct pt [x y z w] #:transparent)
+
+(define (part1 input)
+  (define world (hash-copy input))
+  (define (simulate world)
+    (define new-world (make-hash))
+    (define min-x (apply min (map pt-x (hash-keys world))))
+    (define max-x (apply max (map pt-x (hash-keys world))))
+    (define min-y (apply min (map pt-y (hash-keys world))))
+    (define max-y (apply max (map pt-y (hash-keys world))))
+    (define min-z (apply min (map pt-z (hash-keys world))))
+    (define max-z (apply max (map pt-z (hash-keys world))))
+    (for* ([x (in-range (- min-x 1) (+ max-x 2))]
+           [y (in-range (- min-y 1) (+ max-y 2))]
+           [z (in-range (- min-z 1) (+ max-z 2))])
+      (define ct (for*/sum ([dx (in-range -1 2)]
+                            [dy (in-range -1 2)]
+                            [dz (in-range -1 2)]
+                            #:unless (and (zero? dx) (zero? dy) (zero? dz))
+                            #:when (hash-ref world (pt (+ x dx) (+ y dy) (+ z dz) 0) #f))
+                           1))
+      (define this (pt x y z 0))
+      (cond
+        [(hash-ref world this #f)
+         (when (or (= 2 ct) (= 3 ct))
+           (hash-set! new-world this #t))]
+        [else
+          (when (= 3 ct)
+            (hash-set! new-world this #t))]))
+    new-world)
+
+  (for ([i (in-range 6)])
+    (set! world (simulate world)))
+  (length (filter identity (hash-values world))))
+
+(define (part2 input)
+  (define world (hash-copy input))
+  (define (simulate world)
+    (define new-world (make-hash))
+    (define min-x (apply min (map pt-x (hash-keys world))))
+    (define max-x (apply max (map pt-x (hash-keys world))))
+    (define min-y (apply min (map pt-y (hash-keys world))))
+    (define max-y (apply max (map pt-y (hash-keys world))))
+    (define min-z (apply min (map pt-z (hash-keys world))))
+    (define max-z (apply max (map pt-z (hash-keys world))))
+    (define min-w (apply min (map pt-w (hash-keys world))))
+    (define max-w (apply max (map pt-w (hash-keys world))))
+    (for* ([x (in-range (- min-x 1) (+ max-x 2))]
+           [y (in-range (- min-y 1) (+ max-y 2))]
+           [z (in-range (- min-z 1) (+ max-z 2))]
+           [w (in-range (- min-w 1) (+ max-w 2))])
+      (define ct (for*/sum ([dx (in-range -1 2)]
+                            [dy (in-range -1 2)]
+                            [dz (in-range -1 2)]
+                            [dw (in-range -1 2)]
+                            #:unless (and (zero? dx) (zero? dy) (zero? dz) (zero? dw))
+                            #:when (hash-ref world (pt (+ x dx) (+ y dy) (+ z dz) (+ w dw)) #f))
+                           1))
+      (define this (pt x y z w))
+      (cond
+        [(hash-ref world this #f)
+         (when (or (= 2 ct) (= 3 ct))
+           (hash-set! new-world this #t))]
+        [else
+          (when (= 3 ct)
+            (hash-set! new-world this #t))]))
+    new-world)
+
+  (for ([i (in-range 6)])
+    (set! world (simulate world)))
+  (length (filter identity (hash-values world))))
+
+;; parse input file
+(define (parse fname)
+  (define input (file->lines fname))
+  (define world (make-hash))
+  (for ([line (in-list input)] [y (in-naturals)])
+    (for ([char (in-string line)] [x (in-naturals)])
+      (when (char=? #\# char)
+        (hash-set! world (pt x y 0 0) #t))))
+  world)
+
+(module+ test
+  (require rackunit)
+  ;; tests here
+  (displayln "no tests :("))
+
+(module+ main
+  (define input (parse "inputs/17"))
+  (answer 17 1 (time (part1 input)))
+  (answer 17 2 (time (part2 input)))
+  (displayln "meow"))