private int DoFlashes()
{
var hasFlashed = new HashSet <Grid2d.Cell>();
grid.ForEach(c => c.Value++);
var flashers = grid.GetCells(c => c.Value > 9 && !hasFlashed.Contains(c));
while (flashers.Any())
{
flashers.ForEach(c =>
{
hasFlashed.Add(c);
grid.GetNeighbors(c).ForEach(n => n.Value++);
});
flashers = grid.GetCells(c => c.Value > 9 && !hasFlashed.Contains(c));
}
hasFlashed.ForEach(c => c.Value = 0);
return(hasFlashed.Count);
}
