36 lines
792 B
Racket
36 lines
792 B
Racket
#lang curly-fn racket
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(require "scripts/aoc.rkt")
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;; solution for day 3
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;; helper functions here
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(define (find input dx dy)
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(for/sum ([j (in-range 0 (vector-length input) dy)] [i (in-range 0 +inf.0 dx)])
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(define line (vector-ref input j))
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(if (~>> (vector-length line) (modulo i) (vector-ref line))
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1 0)))
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(define (part1 input)
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(find input 3 1))
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(define (part2 input)
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(for/product ([args (in-list '((1 1) (3 1) (5 1) (7 1) (1 2)))])
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(apply find input args)))
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(module+ main
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(define input
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(for/vector ([line (in-list (file->lines "inputs/3"))])
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(for/vector ([char (in-string line)])
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(match char
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[#\. #f]
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[#\# #t]))))
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;; part 1
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(answer 3 1 (part1 input))
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;; part 2
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(answer 3 2 (part2 input))
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(displayln "meow"))
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