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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 /aoc2020/day-03/day-03.rkt
parentfafbeaf9e3c09ba7a5bea7e47d5736001f8a5aa1 (diff)
downloadgleam_aoc-8ab65dc2da1742eb86ec636c50c7018385b68167.tar.gz
gleam_aoc-8ab65dc2da1742eb86ec636c50c7018385b68167.zip
prep for 2023, renaming for consistency
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+#lang racket
+(require "../../jj-aoc.rkt"
+ threading)
+
+(define (check-for-trees run rise)
+ (for*/sum ([(row i) (in-indexed (port->lines (open-day 3 2020)))]
+ #:when (= 0 (modulo i rise))
+ [possible-tree (in-value (sequence-ref (in-cycle row) (* (/ run rise) i)))]
+ #:when (and (char=? possible-tree #\#)))
+ 1))
+
+;; part 1
+(check-for-trees 3 1)
+
+;; part 2
+(~>> '((1 1) (3 1) (5 1) (7 1) (1 2)) (map (curry apply check-for-trees)) (apply *))