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| -rw-r--r-- | aoc2023-other/day-19/day-19.rkt~ | 116 |
1 files changed, 0 insertions, 116 deletions
diff --git a/aoc2023-other/day-19/day-19.rkt~ b/aoc2023-other/day-19/day-19.rkt~ deleted file mode 100644 index be47f26..0000000 --- a/aoc2023-other/day-19/day-19.rkt~ +++ /dev/null @@ -1,116 +0,0 @@ -#lang racket - -(require advent-of-code - threading - data/applicative - data/monad - megaparsack - megaparsack/text - racket/struct) - -(struct part (x m a s) #:transparent) -(struct rule (rating comparison threshold action) #:transparent) -(struct just (action) #:transparent) -(struct interval (from to)) - -(match-define (list raw-workflows raw-parts) - (~> (fetch-aoc-input (find-session) 2023 19 #:cache #true) - (string-split "\n\n") - (map (curryr string-split "\n") _))) - -(define/match (to-getter _) - [(#\x) part-x] - [(#\m) part-m] - [(#\a) part-a] - [(#\s) part-s]) - -(define/match (to-comp _) - [(#\>) >] - [(#\<) <]) - -(define/match (to-action _) - [('(#\R)) 'reject] - [('(#\A)) 'accept] - [(name) (apply string name)]) - -(define rule/p - (do (or/p - (try/p (do [rating <- (char-in/p "xmas")] - [comparison <- (char-in/p "<>")] - [threshold <- integer/p] - (char/p #\:) - [action <- (many+/p letter/p)] - (pure (rule (to-getter rating) (to-comp comparison) threshold (to-action action))))) - (do [name <- (many+/p letter/p)] (pure (just (to-action name))))))) -(define rules/p - (do [name <- (many+/p letter/p)] - (char/p #\{) - [rules <- (many+/p rule/p #:sep (char/p #\,))] - (char/p #\}) - (pure (cons (list->string name) rules)))) - -(define rating/p (do letter/p (char/p #\=) integer/p)) -(define parts/p - (do (string/p "{") - [ratings <- (many/p rating/p #:sep (char/p #\,) #:min 4 #:max 4)] - (string/p "}") - (pure (apply part ratings)))) - -(define workflows - (~>> raw-workflows (map (λ~>> (parse-string rules/p) parse-result!)) make-immutable-hash)) -(define parts (map (λ~>> (parse-string parts/p) parse-result!) raw-parts)) - -;; part 1 - -(define (evaluate-workflow p [workflow-name "in"]) - (define rules (hash-ref workflows workflow-name)) - (match (evaluate-rules p rules) - ['accept (~> p struct->list (apply + _))] - ['reject 0] - [name (evaluate-workflow p name)])) - -(define (evaluate-rules p rules) - (match rules - [(list* (just action) _) action] - [(list* (rule rating comparison threshold action) _) - #:when (comparison (rating p) threshold) - action] - [(list* _ tail) (evaluate-rules p tail)])) - -(for/sum ([p (in-list parts)]) (evaluate-workflow p)) - -;; part 2 - -(define (part-update-range pr rating interval) - (match rating - [(== part-x) (struct-copy part pr (x interval))] - [(== part-m) (struct-copy part pr (m interval))] - [(== part-a) (struct-copy part pr (a interval))] - [(== part-s) (struct-copy part pr (s interval))])) - -(define (evaluate-workflow-on-range pr [workflow-name "in"]) - (define rules (hash-ref workflows workflow-name)) - (evaluate-rules-on-range pr rules)) - -(define (evaluate-rules-on-range pr rules) - (match rules - [(list* (just 'accept) _) - (~> pr struct->list (map (λ (i) (add1 (- (interval-to i) (interval-from i)))) _) (apply + _))] - [(list* (just 'reject) _) 0] - [(list* (just name) _) (evaluate-workflow-on-range pr name)] - [(list* (rule rating (== <) threshold action) tail) - (match-define (interval i-min i-max) (rating pr)) - (define keep-i (part-update-range pr rating (interval i-min (sub1 threshold)))) - (define pass-i (part-update-range pr rating (interval threshold i-max))) - (+ (evaluate-rules-on-range (part-update-range pr rating keep-i) (list (just action))) - (evaluate-rules-on-range (part-update-range pr rating pass-i) tail))] - [(list* (rule rating (== >) threshold action) tail) - (match-define (interval i-min i-max) (rating pr)) - (define keep-i (part-update-range pr rating (interval (add1 threshold) i-max))) - (define pass-i (part-update-range pr rating (interval i-min threshold))) - (+ (evaluate-rules-on-range (part-update-range pr rating keep-i) (list (just action))) - (evaluate-rules-on-range (part-update-range pr rating pass-i) tail))])) - -(define start-interval (interval 1 4000)) - -(evaluate-workflow-on-range (part start-interval start-interval start-interval start-interval))
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