Day 2-2

day2.erl

@@ -6,10 +6,19 @@ solve(InputData) ->
 	RoundData = binary:split(InputData, <<$\n>>, [trim_all, global]),
 	Rounds = lists:map(fun parse_round/1, RoundData),
 	RoundPoints = lists:map(fun score_round/1, Rounds),
-	{lists:sum(RoundPoints), none}.
+
+	Rounds2 = lists:map(fun parse_round2/1, RoundData),
+	RoundPoints2 = lists:map(fun score_round/1, Rounds2),
+	{lists:sum(RoundPoints), lists:sum(RoundPoints2)}.
 
 parse_round(<<TheirCode, $\s, YourCode>>) -> {parse_theirs(TheirCode), parse_yours(YourCode)}.
 
+parse_round2(<<TheirCode, $\s, OutcomeCode>>) ->
+	OutcomeScore = parse_outcome_points(OutcomeCode),
+	TheirShape = parse_theirs(TheirCode),
+	[YourShape] = [Shape || Shape <- [rock, paper, scissors], round_points({TheirShape, Shape}) == OutcomeScore],
+	{TheirShape, YourShape}.
+
 score_round(Round = {_Theirs, Yours}) -> round_points(Round) + shape_points(Yours).
 
 parse_theirs($A) -> rock;
@@ -20,6 +29,10 @@ parse_yours($X) -> rock;
 parse_yours($Y) -> paper;
 parse_yours($Z) -> scissors.
 
+parse_outcome_points($X) -> 0;
+parse_outcome_points($Y) -> 3;
+parse_outcome_points($Z) -> 6.
+
 round_points({rock, paper}) -> 6;
 round_points({paper, scissors}) -> 6;
 round_points({scissors, rock}) -> 6;