day2 - a bit overcomplicated :)

bin/d2/dune

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+(executable
+ (public_name d2)
+ (name main)
+ (libraries core utils))

bin/d2/main.ml

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+type choice
+    = Rock
+    | Paper
+    | Scissors
+
+let int_of_choice = function
+    | Rock -> 1
+    | Paper -> 2
+    | Scissors -> 3
+
+let choice_of_string = function
+    | "A" | "X" -> Rock
+    | "B" | "Y" -> Paper
+    | "C" | "Z" -> Scissors
+    |        _  -> failwith "invalid choice" ;;
+
+type outcome
+    = Draw
+    | Win
+    | Lose
+
+let int_of_outcome = function
+    | Lose -> 0
+    | Draw -> 3
+    | Win -> 6
+
+let outcome_of_string = function
+    | "X" -> Lose
+    | "Y" -> Draw
+    | "Z" -> Win
+    |  _  -> failwith "invalid choice"
+
+let choice_of_outcome oponent = function
+    | Win -> if oponent = Rock then Paper else if oponent = Paper then Scissors else Rock
+    | Lose -> if oponent = Rock then Scissors else if oponent = Paper then Rock else Paper
+    | Draw -> if oponent = Rock then Rock else if oponent = Paper then Paper else Scissors
+
+let outcome me oponent =
+    match int_of_choice me - int_of_choice oponent with
+    | -1 |  2 -> Lose
+    |  1 | -2 -> Win
+    |       _ -> Draw
+
+let solve f l = l
+    |> List.map (fun line -> line
+                    |> String.split_on_char ' '
+                    |> (fun l -> (List.hd l, List.tl l |> List.hd))
+                    |> f
+                    |> (fun (oponent, me) -> ((outcome me oponent) |> int_of_outcome) + int_of_choice me))
+    |> List.fold_left (+) 0
+
+let d2_1 = solve (fun (oponent_s, me_s) ->
+    (choice_of_string oponent_s, choice_of_string me_s))
+
+let d2_2 = solve (fun (oponent_s, outcome_s) ->
+    (choice_of_string oponent_s, outcome_of_string outcome_s)
+    |> (fun (oponent, outcome) -> (oponent, (choice_of_outcome oponent outcome))))
+
+open Utils
+
+let _ = "\n1: " ^ (string_of_int (read_file "bin/d2/input.txt" |> d2_1)) ^
+        "\n2: " ^ (string_of_int (read_file "bin/d2/input.txt" |> d2_2)) |> print_endline