public void Part2()
{
string data = IO.ReadFile(Path.Combine(Directory.GetCurrentDirectory(), "input1.txt"));
Dictionary <Tuple <int, int>, Node> grid = new Dictionary <Tuple <int, int>, Node>();
string[] lines = data.Split("\r\n");
int maxRow = int.MinValue;
int i = 0;
foreach (string line in lines)
{
int[] numbers = line.ToList().Select(x => int.Parse(x.ToString())).ToArray();
maxRow = numbers.Length;
for (int j = 0; j < numbers.Length; j++)
{
grid.Add(Tuple.Create(i, j), new Node(i, j, numbers[j], grid));
}
i++;
}
List <Node> lowPoints = new();
foreach (var node in grid.Values)
{
if (node.IsLowPoint(i, maxRow))
{
lowPoints.Add(node);
}
}
List <Basin> basins = new();
// All basins flow to a low point so start from low point.
foreach (Node n in lowPoints)
{
if (!n.IsLowPoint(i, maxRow) || n.IsInBasin)
{
continue;
}
Basin b = new Basin(n, grid, i, maxRow);
basins.Add(b);
}
// Sort from greatest to least
basins.Sort((a, b) => b.Size - a.Size);
// Take the top 3 and multiply
Assert.Equal(0, basins.Take(3).Aggregate(1, (count, b) => count * b.Size));
}
public void AddToBasin(Basin b)
{
this.basin = b;
}