diff --git a/2024/src/core.clj b/2024/src/core.clj
index 7139ba6..93eb232 100644
--- a/2024/src/core.clj
+++ b/2024/src/core.clj
@@ -54,3 +54,11 @@
   "mapv mapv mapv f coll"
   [f coll]
   (mapv (partial mapv (partial mapv f)) coll))
+
+(defn partition-by-counts [counts coll]
+  (->> counts
+       (reduce (fn [[acc coll] c]
+                 (let [[a b] (split-at c coll)]
+                   [(conj acc a) b]))
+               [[] coll])
+       first))
diff --git a/2024/src/day09.clj b/2024/src/day09.clj
index af5689d..e8975b8 100644
--- a/2024/src/day09.clj
+++ b/2024/src/day09.clj
@@ -3,20 +3,9 @@
    [core :as c]
    [input-manager :refer [get-input]]))
 
-(defn partition-by-counts [counts coll]
-  (loop [[c & cs] counts
-         acc []
-         coll coll]
-    (cond
-      (nil? c) acc
-      :else (let [[a b] (split-at c coll)]
-              (recur cs (conj acc a) b)))))
-
-(def input (->>
-            ; (first (get-input 9))
-            "2333133121414131402"
-            (map str)
-            (map parse-long)))
+(def input (->> (first (get-input 9))
+                (map str)
+                (map parse-long)))
 
 (def smol-nums (->> input (take-nth 2) (into [])))
 (def smol-spaces (->> input rest (take-nth 2) (into [])))
@@ -24,7 +13,7 @@
 ;; part 1
 (let [forward (map-indexed #(repeat %2 %1) smol-nums)]
   (->> forward reverse flatten
-       (partition-by-counts smol-spaces)
+       (c/partition-by-counts smol-spaces)
        (interleave forward)
        flatten
        (take (reduce + smol-nums))