54 lines
1.3 KiB
Racket
54 lines
1.3 KiB
Racket
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#lang curly-fn racket
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(require "scripts/aoc.rkt")
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;; solution for day 25
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(define *mod* 20201227)
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(define (loop subject times)
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(for/fold ([val 1]) ([_ (in-range (+ 0 times))])
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(remainder (* val subject) *mod*)))
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(define (part1 input)
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(match-define (list you door) input)
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(define you-loops #f)
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(define door-loops #f)
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(for/fold ([val 1]) ([loops (in-range 0 +inf.0)] #:break (and you-loops door-loops))
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(when (= val you)
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(set! you-loops loops))
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(when (= val door)
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(set! door-loops loops))
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(remainder (* val 7) *mod*))
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; (displayln you-loops)
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; (displayln door-loops)
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(displayln you-loops)
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(displayln (loop 7 you-loops))
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(displayln you)
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(displayln door-loops)
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(displayln (loop 7 door-loops))
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(displayln door)
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; (displayln (loop door-loops you-loops))
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; (displayln (loop you-loops door-loops))
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; (displayln (loop 17807724 8))
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; (displayln (loop 5764801 11))
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(loop you door-loops))
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; (part1 (list 5764801 17807724))
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; (error)
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;; parse input file
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(define (parse fname)
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(define input (file->lines fname))
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(map string->number input))
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(module+ test
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(require rackunit)
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;; tests here
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(displayln "no tests :("))
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(module+ main
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(define input (parse "inputs/25"))
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(answer 25 1 (time (part1 input)))
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(aoc-finish)
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(displayln "meow"))
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