#lang curly-fn racket

(require "scripts/aoc.rkt")

;; solution for day 3

;; helper functions here
(define (find input dx dy)
  (for/sum ([j (in-range 0 (vector-length input) dy)] [i (in-range 0 +inf.0 dx)])
    (define line (vector-ref input j))
    (if (~>> (vector-length line) (modulo i) (vector-ref line))
      1 0)))

(define (part1 input)
  (find input 3 1))

(define (part2 input)
  (for/product ([args (in-list '((1 1) (3 1) (5 1) (7 1) (1 2)))])
    (apply find input args)))

(module+ main
  (define input
    (for/vector ([line (in-list (file->lines "inputs/3"))])
      (for/vector ([char (in-string line)])
        (match char
          [#\. #f]
          [#\# #t]))))

  ;; part 1
  (answer 3 1 (part1 input))

  ;; part 2
  (answer 3 2 (part2 input))

  (displayln "meow"))