feat(2025d6): add skeleton for part 2

3 files changed, 55 insertions, 0 deletions

diff --git a/2025/ocaml/lib/application/d06p02.ml b/2025/ocaml/lib/application/d06p02.ml
new file mode 100644
index 0000000..9425810
--- /dev/null
+++ b/2025/ocaml/lib/application/d06p02.ml
@@ -0,0 +1,50 @@
+let err_empty_input = "input is empty"
+
+let log_matrix matrix =
+  let open Domain.Matrix in
+  Logs.debug (fun m -> m "%s" (M.of_list matrix |> M.pp (fun elt -> elt)))
+
+let log_list lst =
+  Logs.debug (fun m ->
+      m "[%s]" (List.fold_left (fun acc i -> acc ^ i ^ "; ") " " lst) )
+
+type operation = Mult | Add
+
+let solve input () =
+  if input = "" then Error err_empty_input
+  else
+    let input' = Parser.columns_of_string input in
+    assert (input' <> []) ;
+    log_matrix input' ;
+    let nums =
+      List.map (List.filter (fun i -> i <> "*" && i <> "+")) input'
+      |> List.map
+         @@ List.map (fun n ->
+             Logs.debug (fun m -> m "peeking: %s" n) ;
+             int_of_string n )
+    and ops =
+      List.map (List.filter (fun i -> i = "*" || i = "+")) input'
+      |> List.concat
+      |> List.map (fun op ->
+          match op with
+          | "*" ->
+              Mult
+          | "+" ->
+              Add
+          | _ ->
+              failwith "case not covered" )
+    in
+    let answer =
+      List.map2
+        (fun op num_lst ->
+          match op with
+          | Add ->
+              List.fold_left (fun acc i -> acc + i) 0 num_lst
+          | Mult ->
+              List.fold_left (fun acc i -> acc * i) 1 num_lst )
+        ops nums
+      |> fun lst ->
+      log_list @@ List.map string_of_int lst ;
+      lst |> List.fold_left ( + ) 0
+    in
+    Ok answer
diff --git a/2025/ocaml/lib/application/d06p02.mli b/2025/ocaml/lib/application/d06p02.mli
new file mode 100644
index 0000000..49444de
--- /dev/null
+++ b/2025/ocaml/lib/application/d06p02.mli
@@ -0,0 +1,4 @@
+val solve : string -> unit -> (int, string) result
+(** [solve input ()] is the solution for the second part of the sixth day of advent of code 2025 for [input].
+    The solution for an empty input is [Error msg].
+    Requires: [input] to be a string. *)
diff --git a/2025/ocaml/lib/presentation/cli.ml b/2025/ocaml/lib/presentation/cli.ml
index 4d979b0..f4c57e6 100644
--- a/2025/ocaml/lib/presentation/cli.ml
+++ b/2025/ocaml/lib/presentation/cli.ml
@@ -35,6 +35,7 @@ let run_day _ = function
   | 6 ->
       let filepath = "../_input/day_06.txt" in
       run_solver "D06P01" Application.D06p01.solve filepath ;
+      run_solver "D06P02" Application.D06p02.solve filepath ;
       0
   | _ ->
       failwith "day not implemented"