private IEnumerable <SeatNeighborhood> GetImmediateSeatNeighborhoods(SeatsMap sm)
{
List <SeatNeighborhood> neighborhoods = new List <SeatNeighborhood>();
foreach (Tuple <int, int> seat in sm.Seats)
{
// Unrolling the cases for all eight directions.
SeatNeighborhood sn = new SeatNeighborhood(seat);
Tuple <int, int> candidate = Tuple.Create(seat.Item1 - 1, seat.Item2 - 1);
if (sm.ContainsKey(candidate))
{
sn.SetNeighbor(Direction.TopLeft, candidate);
}
candidate = Tuple.Create(seat.Item1 - 1, seat.Item2);
if (sm.ContainsKey(candidate))
{
sn.SetNeighbor(Direction.Top, candidate);
}
candidate = Tuple.Create(seat.Item1 - 1, seat.Item2 + 1);
if (sm.ContainsKey(candidate))
{
sn.SetNeighbor(Direction.TopRight, candidate);
}
candidate = Tuple.Create(seat.Item1, seat.Item2 + 1);
if (sm.ContainsKey(candidate))
{
sn.SetNeighbor(Direction.Right, candidate);
}
candidate = Tuple.Create(seat.Item1 + 1, seat.Item2 + 1);
if (sm.ContainsKey(candidate))
{
sn.SetNeighbor(Direction.BottomRight, candidate);
}
candidate = Tuple.Create(seat.Item1 + 1, seat.Item2);
if (sm.ContainsKey(candidate))
{
sn.SetNeighbor(Direction.Bottom, candidate);
}
candidate = Tuple.Create(seat.Item1 + 1, seat.Item2 - 1);
if (sm.ContainsKey(candidate))
{
sn.SetNeighbor(Direction.BottomLeft, candidate);
}
candidate = Tuple.Create(seat.Item1, seat.Item2 - 1);
if (sm.ContainsKey(candidate))
{
sn.SetNeighbor(Direction.Left, candidate);
}
yield return(sn);
}
}
private IEnumerable <SeatNeighborhood> GetClosestSeatNeighborhoods(SeatsMap sm)
{
List <SeatNeighborhood> neighborhoods = new List <SeatNeighborhood>();
foreach (Tuple <int, int> seat in sm.Seats)
{
SeatNeighborhood sn = new SeatNeighborhood(seat);
foreach (SeatNeighborhood neighborhood in neighborhoods)
{
if (TryGetDirection(neighborhood.Seat, seat, out var direction))
{
Direction opposite = GetOppositeDirection(direction);
Tuple <int, int> neighbor = neighborhood.GetNeighbor(direction);
if (neighbor is Tuple <int, int> )
{
int neighborDist = GetManhattanDistance(neighbor, neighborhood.Seat);
int seatDist = GetManhattanDistance(seat, neighborhood.Seat);
if (seatDist < neighborDist)
{
neighborhood.SetNeighbor(direction, seat);
sn.SetNeighbor(opposite, neighborhood.Seat);
}
}
else
{
neighborhood.SetNeighbor(direction, seat);
sn.SetNeighbor(opposite, neighborhood.Seat);
}
}
}
neighborhoods.Add(sn);
}
return(neighborhoods);
}
