object PartOne(string input)
{
var painted = new HashSet <Point>();
var sif = new Sif();
var direction = Direction.Up;
var location = new Point(0, 0);
var vm = new IntCode(input);
while (vm.State != ProgramState.Finished)
{
var currentColor = sif.GetColor(location);
currentColor = currentColor == Sif.Color.Transparent ? Sif.Color.Black : currentColor;
vm.ProvideInput((long)currentColor);
vm.RunToNextInputOrFinished();
// Get the output (if any)
if (vm.HasOutput)
{
var color = (Sif.Color)vm.ReadOutput();
sif.SetColor(location, color);
painted.Add(location);
var turn = vm.ReadOutput();
if (turn == 0)
{
// Turn left
direction = (Direction)(((int)direction - 1 + 4) % 4);
}
else
{
// Turn right
direction = (Direction)(((int)direction + 1) % 4);
}
switch (direction)
{
case Direction.Up:
location = new Point(location.X, location.Y - 1);
break;
case Direction.Right:
location = new Point(location.X + 1, location.Y);
break;
case Direction.Down:
location = new Point(location.X, location.Y + 1);
break;
case Direction.Left:
location = new Point(location.X - 1, location.Y);
break;
default:
throw new ArgumentOutOfRangeException();
}
}
}
return(painted.Count);
}
object PartTwo(string input)
{
var sif = new Sif();
var direction = Direction.Up;
var location = new Point(0, 0);
sif.SetColor(location, Sif.Color.White);
var vm = new IntCode(input);
while (vm.State != ProgramState.Finished)
{
var currentColor = sif.GetColor(location);
var vmInput = currentColor == Sif.Color.White ? 1 : 0;
vm.ProvideInput(vmInput);
vm.RunToNextInputOrFinished();
// Get the output (if any)
if (vm.HasOutput)
{
var color = (Sif.Color)vm.ReadOutput();
sif.SetColor(location, color);
var turn = vm.ReadOutput();
if (turn == 0)
{
// Turn left
direction = (Direction)(((int)direction - 1 + 4) % 4);
}
else
{
// Turn right
direction = (Direction)(((int)direction + 1) % 4);
}
switch (direction)
{
case Direction.Up:
location = new Point(location.X, location.Y - 1);
break;
case Direction.Right:
location = new Point(location.X + 1, location.Y);
break;
case Direction.Down:
location = new Point(location.X, location.Y + 1);
break;
case Direction.Left:
location = new Point(location.X - 1, location.Y);
break;
default:
throw new ArgumentOutOfRangeException();
}
}
}
// Gah. Should've trusted my instincts and made the SIF OCR.
sif.Draw(Console.Out);
return("JZPJRAGJ");
}