1 files changed, 0 insertions, 32 deletions
diff --git a/aoc2023-racket/day-09/day-09.rkt b/aoc2023-racket/day-09/day-09.rkt
deleted file mode 100644
index 5eda1eb..0000000
--- a/aoc2023-racket/day-09/day-09.rkt
+++ /dev/null
@@ -1,32 +0,0 @@
-#lang racket
-
-(require advent-of-code
-         threading)
-
-(define histories
-  (for/list ([raw-history (in-lines (open-aoc-input (find-session) 2023 9 #:cache #true))])
-    (~>> raw-history 
-         string-split 
-         (map string->number))))
-
-(define (constant? xs) 
-  (= 1 (length (remove-duplicates xs))))
-
-(define/match (derivative xs)
-  [((list a b)) (list (- b a))]
-  [((list* a b _)) (cons (- b a) (derivative (rest xs)))])
-
-(define (extrapolate xs) 
-  (if (constant? xs) 
-      (car xs) 
-      (+ (last xs) (extrapolate (derivative xs)))))
-
-;; part 1
-(~>> histories 
-     (map extrapolate) 
-     (apply +))
-
-;; part 2
-(~>> histories 
-     (map (λ~> reverse extrapolate)) 
-     (apply +))