static void Main(string[] args)
{
var stopwatch = Stopwatch.StartNew();
// keep track of matches
var matches = new List <HexTile>();
// keep track of ring we're currently processing
var ring = 0;
var index = 0;
while (matches.Count < 2000)
{
var tile = HexTile.FromIndex(++index);
// starting a new ring?
var tmp = tile.Ring;
if (tmp != ring)
{
ring = tmp;
Console.WriteLine($"Checking Ring {tmp} (start index {tile.Index}), found {matches.Count} tiles so far.");
}
// walk all neighbors
var neighbor = tile.GetNeighbor(Direction.North);
// NOTE: need arbitrarily large integer here, as 128 bit (decimal) are not sufficient
BigInteger result = neighbor.Index;
neighbor = tile.GetNeighbor(Direction.NorthEast);
result *= neighbor.Index;
neighbor = tile.GetNeighbor(Direction.NorthWest);
result *= neighbor.Index;
neighbor = tile.GetNeighbor(Direction.South);
result *= neighbor.Index;
neighbor = tile.GetNeighbor(Direction.SouthEast);
result *= neighbor.Index;
neighbor = tile.GetNeighbor(Direction.SouthWest);
result *= neighbor.Index;
// check if product is devisable by value of tile
if (result % tile.Index == 0)
{
matches.Add(tile);
}
}
stopwatch.Stop();
Console.WriteLine($"Found {matches.Count} matches in {stopwatch.Elapsed.TotalSeconds}s");
var lastMatch = matches.Last();
Console.WriteLine($"Last match was {lastMatch} with the following neighbors:");
Console.WriteLine($"N : {lastMatch.GetNeighbor(Direction.North)}");
Console.WriteLine($"NW: {lastMatch.GetNeighbor(Direction.NorthWest)}");
Console.WriteLine($"SW: {lastMatch.GetNeighbor(Direction.SouthWest)}");
Console.WriteLine($"S : {lastMatch.GetNeighbor(Direction.South)}");
Console.WriteLine($"SE: {lastMatch.GetNeighbor(Direction.SouthEast)}");
Console.WriteLine($"NE: {lastMatch.GetNeighbor(Direction.NorthEast)}");
Console.WriteLine("Hit any key to exit.");
Console.ReadKey();
}
