Data commit

Task/Monty-Hall-problem/Erlang/monty-hall-problem.erl

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+-module(monty_hall).
+
+-export([main/0]).
+
+main() ->
+	random:seed(now()),
+	{WinStay, WinSwitch} = experiment(100000, 0, 0),
+	io:format("Switching wins ~p times.\n", [WinSwitch]),
+	io:format("Staying wins ~p times.\n", [WinStay]).
+
+experiment(0, WinStay, WinSwitch) ->
+	{WinStay, WinSwitch};
+experiment(N, WinStay, WinSwitch) ->
+	Doors = setelement(random:uniform(3), {0,0,0}, 1),
+	SelectedDoor = random:uniform(3),
+	OpenDoor = open_door(Doors, SelectedDoor),
+	experiment(
+		N - 1,
+		WinStay + element(SelectedDoor, Doors),
+		WinSwitch + element(6 - (SelectedDoor + OpenDoor), Doors) ).
+
+open_door(Doors,SelectedDoor) ->
+	OpenDoor = random:uniform(3),
+	case (element(OpenDoor, Doors) =:= 1) or (OpenDoor =:= SelectedDoor) of
+		true -> open_door(Doors, SelectedDoor);
+		false -> OpenDoor
+	end.