public static Facing Turn(this Facing facing, int n)
{
n = n % 4;
for (int i = n; i > 0; i--)
{
facing = facing.TurnRight();
}
for (int i = n; i < 0; i++)
{
facing = facing.TurnLeft();
}
return(facing);
}
public static Facing TurnRight(this Facing facing)
{
return(facing.TurnLeft().Mirror());
}
static void Main(string[] args)
{
int y = -12;
Dictionary <Point, NodeState> states = new Dictionary <Point, NodeState>();
Point cur = new Point(0, 0);
Facing facing = new Facing();
int infectCount = 0;
foreach (string input in FileIterator.Create("./input.txt"))
{
int x = -12;
foreach (char c in input)
{
if (c == '#')
{
states.Add(new Point(x, y), NodeState.Infected);
}
else
{
states.Add(new Point(x, y), NodeState.Clean);
}
x++;
}
y++;
}
for (int i = 0; i < 10000000; i++)
{
if (!states.ContainsKey(cur))
{
states.Add(cur, NodeState.Clean);
}
NodeState curState = states[cur];
switch (curState)
{
case NodeState.Clean:
states[cur] = NodeState.Weakened;
facing.TurnLeft();
break;
case NodeState.Weakened:
states[cur] = NodeState.Infected;
infectCount++;
break;
case NodeState.Infected:
states[cur] = NodeState.Flagged;
facing.TurnRight();
break;
case NodeState.Flagged:
states[cur] = NodeState.Clean;
facing.TurnRight();
facing.TurnRight();
break;
}
cur = facing.Move(cur);
}
Console.WriteLine($"The answer is {infectCount}");
Console.ReadKey(true);
}
