public override string?CalculateSolutionPartTwo()
{
IDynamicIndexable2D <NodeState> nodes = _initialNodeStates.AsIndexable().ToDynamicIndexable();
Position position = (nodes.Length0 / 2, nodes.Length1 / 2);
Direction direction = Direction.North;
int count = 0;
for (int i = 0; i < 10_000_000; i++)
{
direction = nodes.GetValueOrDefault(position.X, position.Y) switch
{
NodeState.Clean => direction.ToLeft(),
NodeState.Weakened => direction,
NodeState.Infected => direction.ToRight(),
NodeState.Flagged => direction.ToReverse(),
_ => throw new InvalidOperationException()
};
nodes[position.X, position.Y] = (NodeState)(((int)nodes.GetValueOrDefault(position.X, position.Y) + 1) % s_nodeStateCount);
if (nodes[position.X, position.Y] == NodeState.Infected)
{
count++;
}
position += direction;
}
return(SolutionPartTwo = count.ToString());
}
}
public static string ToString <T>(this IDynamicIndexable2D <T> source, Func <T, char> charSelector, bool screenMode = false)
{
var builder = new StringBuilder(source.Length0 * (source.Length1 + Environment.NewLine.Length));
int?row = null;
foreach (Position pos in source.EnumeratePositions(screenMode))
{
if (row.HasValue && (screenMode ? pos.Y : pos.X) != row.Value)
{
builder.Append(Environment.NewLine);
}
row = screenMode ? pos.Y : pos.X;
builder.Append(charSelector(source[pos]));
}
return(builder.ToString());
}
public DynamicIndexable2DEnumerator(IDynamicIndexable2D <TValue> values)
{
_values = values;
Reset();
}
public static IEnumerable <Position> EnumeratePositions <T>(this IDynamicIndexable2D <T> source)
{
return(source.EnumeratePositions(source.Start0, source.Length0, source.Start1, source.Length1));
}
public static IEnumerable <Position> EnumeratePositions <T>(this IDynamicIndexable2D <T> source, Func <T, bool> predicate,
Position?after = null, Position?before = null, bool screenMode = false)
{
return(source.EnumeratePositions(source.Start0, source.Length0, source.Start1, source.Length1, predicate, after, before,
screenMode: screenMode));
}
public static IEnumerable <Position> EnumeratePositions <T>(this IDynamicIndexable2D <T> source, bool screenMode = false)
{
return(source.EnumeratePositions(source.Start0, source.Length0, source.Start1, source.Length1, screenMode: screenMode));
}
