40 lines
1.2 KiB
Racket
40 lines
1.2 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 5
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;; helper functions here
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(define (part1 input)
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(apply max
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(for/list ([line (in-list input)])
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(match-define (list _ rowstr colstr) (regexp-match #px"^([FB]{7})([LR]{3})$" line))
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(define row (string->number (string-replace (string-replace rowstr "F" "0") "B" "1") 2))
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(define col (string->number (string-replace (string-replace colstr "L" "0") "R" "1") 2))
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(+ (* row 8) col))))
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(define (part2 input)
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(define seats
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(for/list ([line (in-list input)])
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(match-define (list _ rowstr colstr) (regexp-match #px"^([FB]{7})([LR]{3})$" line))
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(define row (string->number (string-replace (string-replace rowstr "F" "0") "B" "1") 2))
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(define col (string->number (string-replace (string-replace colstr "L" "0") "R" "1") 2))
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(+ (* row 8) col)))
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(for/first ([id (in-range (apply min seats) (apply max seats))]
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#:when (and (not (member id seats))
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(member (add1 id) seats)
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(member (sub1 id) seats)))
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id))
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(module+ main
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(define input (file->lines "inputs/5"))
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;; part 1
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(answer 5 1 (part1 input))
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;; part 2
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(answer 5 2 (part2 input))
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(displayln "meow"))
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