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-rw-r--r--aoc2023-racket/day-24/day-24a.rkt51
1 files changed, 0 insertions, 51 deletions
diff --git a/aoc2023-racket/day-24/day-24a.rkt b/aoc2023-racket/day-24/day-24a.rkt
deleted file mode 100644
index 31f526d..0000000
--- a/aoc2023-racket/day-24/day-24a.rkt
+++ /dev/null
@@ -1,51 +0,0 @@
-#lang rosette
-
-(require advent-of-code
- threading)
-
-(struct hail (posn vel) #:transparent)
-(struct posn (x y z) #:transparent)
-(struct vel (x y z) #:transparent)
-
-(define input (fetch-aoc-input (find-session) 2023 24 #:cache #true))
-
-(define LOWER-BOUND 200000000000000)
-(define UPPER-BOUND 400000000000000)
-
-(define (->struct f str)
- (~> str (string-split _ ",") (map (λ~> string-trim string->number) _) (apply f _)))
-
-(define (parse-hail-record str)
- (match-define (list p v) (string-split str " @ "))
- (hail (->struct posn p)
- (->struct vel v)))
-
-(define hail-paths
- (for/list ([hail (in-list (string-split input "\n"))])
- (parse-hail-record hail)))
-
-;; part 1
-(define (valid-intersection? h1 h2)
- (match-define (hail (posn x1 y1 _) (vel vx1 vy1 _)) h1)
- (match-define (hail (posn x2 y2 _) (vel vx2 vy2 _)) h2)
- (cond
- [(= (* vy1 vx2) (* vx1 vy2)) #f]
- [else
- (define t1 (/ (- (* vy2 (- x1 x2)) (* vx2 (- y1 y2)))
- (- (* vy1 vx2) (* vx1 vy2))))
- (define t2 (/ (- (* vy1 (- x2 x1)) (* vx1 (- y2 y1)))
- (- (* vy2 vx1) (* vx2 vy1))))
-
- (define x (+ x1 (* t1 vx1)))
- (define y (+ y1 (* t1 vy1)))
-
- (and (<= LOWER-BOUND x UPPER-BOUND)
- (<= LOWER-BOUND y UPPER-BOUND)
- (<= 0 t1)
- (<= 0 t2))]))
-
-(for/sum ([(trial-paths) (in-combinations hail-paths 2)] ;
- #:when (apply valid-intersection? trial-paths))
- 1)
-
-;; part 2 - see day-24b.rkt