public static WaitingArea EvolveWaitingAreaUntilSteadyState(
WaitingArea initialWaitingArea,
EvolutionRules evolutionRules)
{
WaitingArea previousState = null;
var nextState = initialWaitingArea;
while (!nextState.Equals(previousState))
{
previousState = nextState;
nextState = GetNextWaitingAreaState(previousState, evolutionRules);
}
return(previousState);
}
public static WaitingArea GetNextWaitingAreaState(
WaitingArea waitingArea,
EvolutionRules evolutionRules)
{
// For each cell:
// If a seat is empty (L) and there are no occupied seats adjacent to it, the seat becomes occupied.
// If a seat is occupied(#) and four or more seats adjacent to it are also occupied, the seat becomes empty.
// Otherwise, the seat's state does not change.
// Floor(.) never changes; seats don't move, and nobody sits on the floor.
var updatedGridCellTypes = new Dictionary <GridPoint, CellType>();
for (int row = 0; row < waitingArea.Height; row++)
{
for (int column = 0; column < waitingArea.Width; column++)
{
var point = new GridPoint(column, row);
var cellType = CellType.Floor;
if (waitingArea.GridCellTypes.ContainsKey(point))
{
cellType = waitingArea.GridCellTypes[point];
}
if (CellType.Floor.Equals(cellType))
{
updatedGridCellTypes.Add(point, cellType);
continue;
}
int numberOfAdjacentOccupiedSeats = GetNumberOfSeenOccupiedSeats(waitingArea, point, evolutionRules.OnlyConsiderAdjacentCells);
if (CellType.ChairOpen.Equals(cellType) && numberOfAdjacentOccupiedSeats == 0)
{
cellType = CellType.ChairOccupied;
}
else if (CellType.ChairOccupied.Equals(cellType) && numberOfAdjacentOccupiedSeats >= evolutionRules.MinimumNumberOfSeenOccupiedSeatsToFlipToEmpty)
{
cellType = CellType.ChairOpen;
}
updatedGridCellTypes.Add(point, cellType);
}
}
var result = new WaitingArea(waitingArea.Width, waitingArea.Width, updatedGridCellTypes);
return(result);
}
