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authorHunky Jimpjorps <thechairman@thechairman.info>2022-12-25 00:44:25 -0500
committerHunky Jimpjorps <thechairman@thechairman.info>2022-12-25 00:44:25 -0500
commit3c73e58c38acdfbac046efb2cbc2c041455911eb (patch)
treefbde75b0f58b4dffb98ac462d8b6e3a7aeb4d73c /2022
parent3f4e251b2e95871b01ce9c33e664bf22f0c415c6 (diff)
downloadgleam_aoc-3c73e58c38acdfbac046efb2cbc2c041455911eb.tar.gz
gleam_aoc-3c73e58c38acdfbac046efb2cbc2c041455911eb.zip
day 25 complete
Diffstat (limited to '2022')
-rw-r--r--2022/day-25/day-25.rkt24
1 files changed, 24 insertions, 0 deletions
diff --git a/2022/day-25/day-25.rkt b/2022/day-25/day-25.rkt
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index 0000000..078cef4
--- /dev/null
+++ b/2022/day-25/day-25.rkt
@@ -0,0 +1,24 @@
+#lang racket
+(require advent-of-code
+ threading)
+
+(define fuel-requirements (port->lines (open-aoc-input (find-session) 2022 25 #:cache #true)))
+
+(define (snafu->decimal snafu)
+ (for/sum ([digit (in-list (~> snafu string->list reverse))] [place (in-naturals)])
+ (define value
+ (match digit
+ [#\= -2]
+ [#\- -1]
+ [c (~> c string string->number)]))
+ (* value (expt 5 place))))
+
+(define (decimal->snafu n [acc '()])
+ (match n
+ [0 (list->string acc)]
+ [n (decimal->snafu (quotient (+ n 2) 5) (cons (string-ref "012=-" (modulo n 5)) acc))]))
+
+;; part 1
+(~> (for/sum ([fuel (in-list fuel-requirements)]) (snafu->decimal fuel)) decimal->snafu)
+
+;; no part 2 メリークリスマス \ No newline at end of file