2 files changed, 22 insertions, 8 deletions
diff --git a/aoc2023-other/day-09/day-09-polynomial.rkt b/aoc2023-other/day-09/day-09-polynomial.rkt
index 31c0d3d..5bacb1f 100644
--- a/aoc2023-other/day-09/day-09-polynomial.rkt
+++ b/aoc2023-other/day-09/day-09-polynomial.rkt
@@ -6,8 +6,12 @@
 
 (define histories
   (for/list ([raw-history (in-lines (open-aoc-input (find-session) 2023 9 #:cache #true))])
-    (~>> raw-history string-split (map string->number))))
+    (~>> raw-history 
+         string-split 
+         (map string->number))))
 
-(for/lists (left right #:result (cons (apply + left) (apply + right)))([history (in-list histories)])
+(for/lists (left right #:result (cons (apply + left) (apply + right)))
+           ([history (in-list histories)])
   (define f (interpolate-at-integer-points history))
-  (values (f -1) (f (length history))))
+  (values (f -1) 
+          (f (length history))))
diff --git a/aoc2023-other/day-09/day-09.rkt b/aoc2023-other/day-09/day-09.rkt
index c632150..5eda1eb 100644
--- a/aoc2023-other/day-09/day-09.rkt
+++ b/aoc2023-other/day-09/day-09.rkt
@@ -5,18 +5,28 @@
 
 (define histories
   (for/list ([raw-history (in-lines (open-aoc-input (find-session) 2023 9 #:cache #true))])
-    (~>> raw-history string-split (map string->number))))
+    (~>> raw-history 
+         string-split 
+         (map string->number))))
 
-(define (constant? xs) (= 1 (length (remove-duplicates xs))))
+(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)))))
+(define (extrapolate xs) 
+  (if (constant? xs) 
+      (car xs) 
+      (+ (last xs) (extrapolate (derivative xs)))))
 
 ;; part 1
-(~>> histories (map extrapolate) (apply +))
+(~>> histories 
+     (map extrapolate) 
+     (apply +))
 
 ;; part 2
-(~>> histories (map (λ~> reverse extrapolate)) (apply +))
+(~>> histories 
+     (map (λ~> reverse extrapolate)) 
+     (apply +))