void eval()
{
List <Cell> cells = grid.GetCells();
List <Cell> toChange = new List <Cell>();
foreach (Cell c in cells)
{
int n = grid.GetNeighbors(c);
if (grid.IsAlive(c))
{
if (n < 2 || n > 3)
{
toChange.Add(c);
}
}
else
{
if (n == 3)
{
toChange.Add(c);
}
}
}
grid.Change(toChange);
}