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#lang racket
(define blueprints
(for/list ([line (file->lines "day19s")])
(match (cdr (map string->number (regexp-match* #rx"[0-9]+" line)))
[(list a b c d e f)
(list (list (list 0 0 0 a) (list 0 0 0 1))
(list (list 0 0 0 b) (list 0 0 1 0))
(list (list 0 0 d c) (list 0 1 0 0))
(list (list 0 f 0 e) (list 1 0 0 0))
(list (list 0 0 0 0) (list 0 0 0 0)))])))
(define (list>? x y)
(let comparing ((x x) (y y))
(cond ((null? x) #f) ; same
((> (car x) (car y)) #t)
((> (car y) (car x)) #f)
(else (comparing (cdr x) (cdr y))))))
(define (key a)
(map + (list-ref a 0) (list-ref a 1)))
(define (take* lst n)
(if (< (length lst) n)
lst
(take lst n)))
(define (run blueprint t)
(let ([todo (list (list (list 0 0 0 0) (list 0 0 0 1)))])
(for ([_ (in-range 0 t)])
(let ([new-todo '()])
(for* ([item1 todo]
[item2 blueprint])
(let ([have (first item1)]
[make (second item1)]
[cost (first item2)]
[more (second item2)])
(when (andmap >= have cost)
(set! new-todo (cons (list (map + have make (map - cost))
(map + make more))
new-todo)))))
(set! todo (take* (sort new-todo list>? #:key key) 2000))))
(first (sort todo list>? #:key key))))
; (pretty-print blueprints)
(run (first blueprints) 24)
(run (second blueprints) 24)
(for/sum ([b blueprints]
[i (in-inclusive-range 1 (length blueprints))])
(* i (caar (run b 24))))
;; 1294
(for/product ([b blueprints]
[i (in-inclusive-range 1 3)])
(caar (run b 32)))
;; 13640
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