46 lines
1.1 KiB
Racket
46 lines
1.1 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 6
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(define (do-race total-time hold-time)
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(define rem-time (- total-time hold-time))
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(* rem-time hold-time))
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(define (part1 input)
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(apply
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*
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(for/list ([time (in-list (first input))] [dist (in-list (second input))])
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(for/fold ([cnt 0]) ([hold (in-range time)])
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(define res (do-race time hold))
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(if (> res dist)
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(add1 cnt)
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cnt)))))
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(define (cvt l)
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(string->number (apply string-append (map number->string l))))
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(define (part2 input)
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(define time (cvt (first input)))
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(define dist (cvt (second input)))
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(for/fold ([cnt 0]) ([hold (in-range time)])
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(define res (do-race time hold))
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(if (> res dist)
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(add1 cnt)
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cnt)))
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(define (parse fname)
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(match-define (list time-str dist-str) (file->lines fname))
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(list (map string->number (rest (string-split time-str)))
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(map string->number (rest (string-split dist-str)))))
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; (dbg (part1 (parse "inputs/6-test1")))
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; (error)
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(module+ main
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(define input (parse "inputs/6"))
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(answer 6 1 (time (part1 input)))
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(answer 6 2 (time (part2 input)))
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(displayln "meow"))
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