From 3c73e58c38acdfbac046efb2cbc2c041455911eb Mon Sep 17 00:00:00 2001 From: Hunky Jimpjorps Date: Sun, 25 Dec 2022 00:44:25 -0500 Subject: day 25 complete --- 2022/day-25/day-25.rkt | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 2022/day-25/day-25.rkt diff --git a/2022/day-25/day-25.rkt b/2022/day-25/day-25.rkt new file mode 100644 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 -- cgit v1.2.3