Day 6-1

day6.erl

@@ -0,0 +1,15 @@
+-module(day6).
+
+-export([solve/1]).
+
+solve(InputData) ->
+	{solve(InputData, 1), none}.
+
+solve(<<A, A, Rest/binary>>, N) -> solve(<<A, Rest/binary>>, N+1);
+solve(<<A, B, A, Rest/binary>>, N) -> solve(<<B, A, Rest/binary>>, N+1);
+solve(<<A, B, C, A, Rest/binary>>, N) -> solve(<<B, C, A, Rest/binary>>, N+1);
+solve(<<A, B, B, Rest/binary>>, N) -> solve(<<B, Rest/binary>>, N+2);
+solve(<<A, B, C, C, Rest/binary>>, N) -> solve(<<C, Rest/binary>>, N+3);
+solve(<<A, B, C, D, _Rest/binary>>, N) when A /= B andalso B /= C andalso C /= D andalso
+					    A /= C andalso B /= D andalso A /= D -> N+3;
+solve(<<_, Rest/binary>>, N) -> solve(Rest, N+1).