#lang curly-fn racket

(require "scripts/aoc.rkt")

;; solution for day 9

;; helper functions here

(define (part1 input)
  (define vec (list->vector input))
  (let/ec exit
    (for ([i (in-range 25 (vector-length vec))])
      (define valid?
        (for*/first ([a (in-range (- i 25) i)] [b (in-range a i)]
                     #:when (= (vector-ref vec i) (+ (vector-ref vec a) (vector-ref vec b)))) #t))
      (unless valid?
        (exit (vector-ref vec i))))))

(define (part2 input)
  (define pt1 10884537)
  (define pt1-i 501)
  (let/ec exit
    (define vec (list->vector input))
    (define (cb args)
      (when (= pt1 (apply + args))
        (exit (+ (apply min args) (apply max args)))))
    (for* ([ct (in-range 3 100)] [i (in-range 0 (- pt1-i ct))])
      (define sub (vector-copy vec i (+ i ct)))
      (cb (vector->list sub)))))

(module+ test
  (require rackunit)
  ;; tests here
  (displayln "no tests :("))

(module+ main
  (define input (file->list "inputs/9"))
  ;; part 1
  (answer 9 1 (part1 input))

  ;; part 2
  (answer 9 2 (part2 input))

  (displayln "meow"))