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#lang racket
(require advent-of-code)
(struct roll (id red green blue))
(define all-games
(for/list ([raw-game (in-list (port->lines (open-aoc-input (find-session) 2023 2)))]
#:do [(define game (string-trim raw-game "Game "))
(match-define (list id trials) (string-split game ": "))])
(for/list ([trial (in-list (string-split trials "; "))])
(for/fold ([acc (roll (string->number id) 0 0 0)])
([color (in-list (string-split trial ", "))])
(match (string-split color)
[(list (app string->number n) "red") (struct-copy roll acc [red n])]
[(list (app string->number n) "green") (struct-copy roll acc [green n])]
[(list (app string->number n) "blue") (struct-copy roll acc [blue n])])))))
;; part 1
(for/sum ([game (in-list all-games)]
#:when (andmap (λ (g) (and ((roll-red g) . <= . 12)
((roll-green g) . <= . 13)
((roll-blue g) . <= . 14)))
game))
(roll-id (first game)))
;; part 2
(for/sum ([game (in-list all-games)])
(define max-cubes
(for/fold ([acc (roll #f 0 0 0)]) ([r (in-list game)])
(roll #f
(max (roll-red acc) (roll-red r))
(max (roll-green acc) (roll-green r))
(max (roll-blue acc) (roll-blue r)))))
(* (roll-red max-cubes) (roll-green max-cubes) (roll-blue max-cubes)))
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