From e5af484c65bb78f99fb3a646bcec796a119a22f3 Mon Sep 17 00:00:00 2001
From: haskal <haskal@awoo.systems>
Date: Sat, 5 Dec 2020 00:12:11 -0500
Subject: [PATCH] day 5: initial solution

---
 5.rkt | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 5.rkt

diff --git a/5.rkt b/5.rkt
new file mode 100644
index 0000000..7dd8454
--- /dev/null
+++ b/5.rkt
@@ -0,0 +1,39 @@
+#lang curly-fn racket
+
+(require "scripts/aoc.rkt")
+
+;; solution for day 5
+
+;; helper functions here
+
+(define (part1 input)
+  (apply max
+    (for/list ([line (in-list input)])
+      (match-define (list _ rowstr colstr) (regexp-match #px"^([FB]{7})([LR]{3})$" line))
+      (define row (string->number (string-replace (string-replace rowstr "F" "0") "B" "1") 2))
+      (define col (string->number (string-replace (string-replace colstr "L" "0") "R" "1") 2))
+      (+ (* row 8) col))))
+
+(define (part2 input)
+  (define seats
+    (for/list ([line (in-list input)])
+      (match-define (list _ rowstr colstr) (regexp-match #px"^([FB]{7})([LR]{3})$" line))
+      (define row (string->number (string-replace (string-replace rowstr "F" "0") "B" "1") 2))
+      (define col (string->number (string-replace (string-replace colstr "L" "0") "R" "1") 2))
+      (+ (* row 8) col)))
+
+  (for/first ([id (in-range (apply min seats) (apply max seats))]
+              #:when (and (not (member id seats))
+                          (member (add1 id) seats)
+                          (member (sub1 id) seats)))
+    id))
+
+(module+ main
+  (define input (file->lines "inputs/5"))
+  ;; part 1
+  (answer 5 1 (part1 input))
+
+  ;; part 2
+  (answer 5 2 (part2 input))
+
+  (displayln "meow"))