1 files changed, 44 insertions, 0 deletions
diff --git a/ocaml/lib/year2024/day01/part02.ml b/ocaml/lib/year2024/day01/part02.ml
new file mode 100644
index 0000000..25c8b7d
--- /dev/null
+++ b/ocaml/lib/year2024/day01/part02.ml
@@ -0,0 +1,44 @@
+(* Day 1: Part 2 *)
+
+let rec count_occurrances_help element acc lst =
+  match lst with
+  | [] -> acc
+  | h :: t ->
+      if h = element then count_occurrances_help element (acc + 1) t
+      else count_occurrances_help element acc t
+
+let count_occurrances element lst = count_occurrances_help element 0 lst
+
+let solve left right =
+  List.map (fun x -> x * count_occurrances x right) left
+  |> List.fold_left ( + ) 0
+
+let left line =
+  let pos = 0 in
+  let len = String.index line ' ' in
+  String.sub line pos len
+
+let right line =
+  let pos = String.rindex line ' ' + 1 in
+  let len = String.length line - pos in
+  String.sub line pos len
+
+let line_to_tuple line = (left line, right line)
+
+let lines_to_lists lines =
+  let tuples = List.map line_to_tuple lines in
+  let left =
+    List.map
+      (fun t ->
+        let l, _ = t in
+        int_of_string l)
+      tuples
+  in
+  let right =
+    List.map
+      (fun t ->
+        let _, r = t in
+        int_of_string r)
+      tuples
+  in
+  (left, right)