all tasks

Task/Sorting-algorithms-Merge-sort/OCaml/sorting-algorithms-merge-sort.ocaml

@@ -0,0 +1,21 @@
+let rec split_at n xs =
+  match n, xs with
+      0, xs ->
+        [], xs
+    | _, [] ->
+        failwith "index too large"
+    | n, x::xs when n > 0 ->
+        let xs', xs'' = split_at (pred n) xs in
+          x::xs', xs''
+    | _, _ ->
+        invalid_arg "negative argument"
+
+let rec merge_sort cmp = function
+    [] -> []
+  | [x] -> [x]
+  | xs ->
+      let xs, ys = split_at (List.length xs / 2) xs in
+        List.merge cmp (merge_sort cmp xs) (merge_sort cmp ys)
+
+let _ =
+  merge_sort compare [8;6;4;2;1;3;5;7;9]